Finally, do you also recognize that the self-tuning feature of the Sniper EFI may not result in an acceptable configuration for your boat and, as such, may require you to seek professional tuning? Free Shipping - Holley Sniper EFI Oxygen Sensors with qualifying orders of $99. My boat is still in winter storage. The new Exhaust manifolds will have wideband O2 bungs for tuning. I have searched thru the forum as much as I can, with not much luck. Part# 554-155. I am a competent mechanic and I have checked all the usual suspect items. (probably with the edelbrock marine 2506 intake). Do you understand that no USCG-approved aftermarket EFI fuel system (including fuel pump, lines, filters, adapters, and hose ends) exists, that installing unapproved components on a boat will make the boat out-of-compliance with USCG regulation and could result in financial loss and legal liability (and that you release us from any liability by proceeding)? I am a competent mechanic and I have checked all the usual suspect items. I was mocking it up at the time. The target A/F value based on load or MAF cfm, and engine speed. I recommend popping for the Master . Seems to have more low end tq and is much smoother power through out the rpm range. GA - As close to the lake as I can afford A powerful, MICRO BlueTooth in dash audio solution! $119.95. Tech Resources. The adapter will be fastened in both metal parts so that no water will reach the O2 sensor. EFI System Pro also has a good bit of tech info on their website. I put mine after the collector only because I have a new exhaust and muffler going in and Ill use a weld in bung and placement will be different. Running? Fortunately, it turns out there are some options. Holley EFI Usb/Can Harness, Sniper Tbi. Thanks for that, Danny. Howell indicates that this adapter was designed for the Chevy type Mercruiser manifold but that it should work on any similar marine wet manifold. Description. Copyright 2017 Cyberspace Automotive Performance, Inc. All Rights Reserved. Even though you now have the USCG-approved Sniper EFI System as an option for your new EFI System you're not quite out of the woods yet. Any exhaust down at engine level or lower will definitely get at LEAST some steam. The test run was great, they have never run so well even when they were new with carbs. Jun 7, 2021. Then if that doesn't work call the tech line they are great! Have you visually verified that all your injectors are spraying? JavaScript is disabled. Air-Fuel Ratio (AFR) - The most common reference term used for mixtures in internal combustion engines. Please consult the Holley Sniper full manual and use this guide for supplemental clarification. No prime, but a second later it's ready to crank 'normally'. The fuel lines and fittings are 3/8s with 8AN fittings and everything on the 60 requires 5/16 fuel line with 6AN fittings) Holley Sniper EFI 550-849 Holley Sniper EFI 2300 Self-Tuning Kit - Shiny Finish. It will crank and run great for 2-15 seconds then die. 02/25/2020. The clamp-on that came with mine wasnt a good fit on my 2" pipe. Capability Range: Professional Only a few hours on the motor but so far so good. 29. I would back-burner the ignition control questions until you get the fuel injection working. Ive got a set of bassett headers for a BBC, ill see if they can fit under the transom. Brass adaptor designed to install heated oxygen sensor in water-cooled marine exhaust risers. Tune the delay relay timing to just miss the prime shot.For cold starts, a simple push-button or switch "choke" override to power the relay during prime would provide it. Installed a Lokar throttle linkage bracket custom made for the Sniper, removing the old one that had been on my Holley 750. I'm using the NTK sensor. Is the O2 sensor on the dyno must have a very long pipe extending past where it is positioned or backwash from the room air will violate the readings as well as any header leaks. . Sadly, no. WARNING: It is against the law to install this part on an Emissions Controlled Vehicle, By Corey A on June 4, 2021 | Verified Owner. Systems that were already designed for marine efi. This runs in the area of $1000 and has everything you need for a basic install on almost any vehicle equipped with a four barrel carb. It could be an instant fix. I am looking for a TBI with full sensors, mainly atmospheric for Sept and Oct and a Idle Air sensor for warm starts.I welcome your thoughts.Regards, I have a boat with twin 3.7 Mercruisers. I took my time soldered every wire connection and routed all the wires carefully to avoid any emt issues. I've been building a TBI system from GM parts to use on a 1987 Wellcraft with the Mercruiser 4 cylinder engine. Anyone ever converted a 1987 3.7L 4cyl Mercruiser engine to EFI. Without the engine running, AFR will read 35.6 The fuel pump will run off a relay in the sniper harness (blue wire) pink wire gets switch/run power to the relay. This doesn't mean it can't be done. I'm having new headers with an O2 sensor bung installed in my car ('79 Vette) soon, to prepare for a Holley Sniper EFI TBI install this winter. The truck started fine after install, and ran down the road ok. I would send an Email to Chris at EFIsystempro. The Holley Super Sniper High Performance EFI kit comes with a coolant temperature sensor and an O2 sensor, both of which must be used for the EFI to work properly. You will still get some water on the engine side of the snails, mainly at low Rs. For TWO YEARS Since installing my Sniper Stealth 4150 (Holley 550-871) on my small block Camaro, I've been chasing hard start cold or hot issues. To those who have installed the Sniper EFI units, please post up some photos of where you tapped the exhaust line to install the Oxygen Sensor's weld bung. Thanks for the feedback on this adapter, Donald. You really want a bigger engine. Why? Some parts are not legal for use in California or other states with similar regulations. Holley EFI has the solutions you need to get your project up and running better than ever! I know from some of the other posts, there have been WBO2 sensor issues. Holley Sniper O2 sensor replacement. It would cost considerably more but a second option that would have added performance benefits would be to switch to a dry manifld such as the headers available from Custom Marine, Inc. Sniper throttle body linkage opens all four barrels evenly when you depress the throttle. Other? B/c what it sometimes perceives as a lean spike is actually raw fuel with no oxygen. Service Oxygen Sensor for Sniper EFI Systems, Service Oxygen Sensor for Terminator X Systems. For this you need a system that can be fully programmed to the extent of the Holley ECU's capability. JavaScript is disabled. The oxygen sensor should be mounted at a point where it can read a good average of all the cylinders on one bank. It may not display this or other websites correctly. This step is only for those installing their Super Sniper EFI on top of a draw-through or Roots-style blower. The sniper fit perfectly on the intake. Sort. -- I particularly like the Daytona Sensors Approach to the Ignition Curve.- Are you pursuing Coast Guard Certification for the Sniper_EFi? They have mods that help. He had one there that was run on a dyno then the fuel map was set and shipped back. The very front would be the safest place. Apr 13, 2017. with the extension. (Assuming it actually releases in November and there are enough units for me to purchase and receive one in December). I do believe that the Holley EFI ECU's have the capability to be programmed to work in this application, but have not yet found anyone who has tackled this task and been fully successful.If you (or anyone else) does make some progress on this, please reply here and let us know what works. The first option is to just buy the injector body and the controller with the wiring harness and sensors. In the event you decided earlier that you are going with the Sniper EFI System you will not have the requisite tuning capability by simply using the included handheld tuner. replaced my original terminator x sensor that was mounted in an exhaust that took on some water and killed the original sensor. If I am reading your post correctly you are using two separate o2 sensors when using headers ? About your only location is in that short area from the log to the port face. I have a 74 bronco, 302, mild cam. Parts List: 1) Holley Sniper 2300 EFI Kit (Do not buy the kit with fuel lines and pump etc. Wideband Oxygen Sensor Extension Cable. This really applies to any O2 sensor regardless of EFI system. This product works with Holley EFI wideband oxygen sensors, part numbers 554-100 and 554-101. This combines the Sniper EFI Self Learning Throttle Body, with an easy to install In-Tank Retrofit Returnless Module, 20 ft of Earl's Vapor Guard Fuel Hose, and the required fittings. I have tried several different settings to get it going, no luck. See Details. Homemade body parts replace the originals as they rot away but it's a 40 on the inside. As I have since added above, the Sniper simply isn't going to be the system to use to tackle this problem. looking at doing the same. Because the fuel maps are built on a speed-density (ie, engine RPM versus manifold air pressure) fueling strategy. Introducing Sniper EFI Master Kits, with a Returnless Retrofit Fuel Module. Was in marine engineering for years. Replacement Sniper and Terminator X O2 Sensor, This part is legal for sale or use on Racing Use Only Vehicles. Put an end to cold start issues, hesitations, vapor . 2. My tune is coincidentally set at 11.5 desired afr, with the failed side as the leanest bank, but the ecu added 15% fuel anyways. Holley recommends a 3/8" fuel supply line. The throttle body has a built in fuel pressure regulator set at 58.5 psi. That is defacto step one in trouble shooting fuel injection systems. CTS (Coolant Temperature Sensor) - Reads engine temperature. Note that this is a different sensor than Holley uses for their Dominator/HP/Terminator/Avenger series. Note the temperature sensor mounted on the back of the driver side head in the above photo. 02 sensors are very heat sensitive, and can detect an exhaust pulsation in a single Header tube, that's why we always wanted to position the sensor into at least 2 opposite firing tubes we running Headers. watch the values in the software for the o2.. once is is done "Heating" and starts to show AFR, wrap the rag round it. I will be calling around to see if I can find someone to help that has experience. Without Headers Steamers location (above) is perfect, up close to the engine where you . The adapter plate installs in between the exhaust manifold and the riser/elbow allowing for the water jackets to still be in place and an o2 sensor to be installed in the still dry exhaust gasses. Sponsored Links (REGISTERED USERS DO NOT SEE THIS POST/AD! There are five significant plug connections to make from the throttle body: Plug into the oxygen sensor. What you are able to accomplish with a Sniper is done exclusively through the setup wizard application on the 3.5-inch handheld.The Temrinator is designed to be set up with it's own setup wizard on the same 3.5-inch handheld display--but since it has a stand-alone ECU, it can also be fully programmed via the Holley laptop software. EFI System Pro had everything I needed for my EFI upgrade. In the case of the car, you can generally get out and walk (run?) I had the pink ecu signal wire connected to a bullet connector on the passenger side . I have twin 502 factory fuel injected Mercs and want to go to adaptive EFI. To take advantage of all the site features, please take a moment to register. Most of you only need to tune 4 points, idling around the marina, part throttle - pulling the rope tight, 1/2-3/4 throttle - cruise, and YeeHaa - WOT. The very basic fuel and spark tables are the limiting aspect, Holley does offer advanced software for more precise tuning. I installed one also on mercruiser 260 hp. Jan 20, 2019. The included fuel system places a 340LPH fuel pump in the tank, which can easily be . The spark must be manually tuned. Add To Cart. Good luck to all. I am interested in upgrading both engines with Pertronix Ignitor or Ignitor II ignition and the Holley Sniper EFI 2300 and the Howell EFI marine O2 sensor adapter. Tips on how to measure the correct location and other considerations when welding in an O2 sensor bung. Taking a look at the holley manual I am thinking about drilling and tapping the front exhaust port on the log for the O2 sensor. Pay close attention to the instructions on O2 sensor placement. I had an o2 sensor fail on a pass yesterday, and flatline at 11.5afr. Whether you're engine swapping your classic car or need to manage 4000 horsepower in your twin-turbocharged drag radial race car, Holley EFI has the solutions you need to get your project up and running better than ever! It's hallmark is its simplicity--but in this case it is also it's shortcoming. In Stock. functioning controller during engine operation. After a few tries by jumping the starter solenoid I then realized the ignition key was in the off position. Here is one on start up tuning. 74 FJ40 confined to the swamp. I had an o2 sensor fail on a pass yesterday, and flatline at 11.5afr. But MAP sensors are very easy to physically implement and are inexpensive. holley sniper efi Holley Sniper EFI Self-Tuning Master Kit - Black Ceramic Finish $1,475.95 Part# 550-511K holley efi 100 PSI Stainless Pressure Sensor $155.95 Part# 554-102 Are you waiting to convert your carbureted vehicle to Sniper EFI, but don't like the idea of mounting an external fuel pump? O2 sensor placement is critical for getting your engine to read the oxygen in the exhaust correctly and can directly impact the performance of your new EFI installation. Hello Chris,Ontario's boating season is about to launch for another year.Do you have any good news to add to your above article, any new marine friendly TBI products?In '08,I installed a Holley 21-700 TBI with the o2 mounted in the manifold to Holly specs. This page was generated at 08:35 AM. Never tried it myself or know anyone fwho has, but Little kids play hooky . big kids play. Seems to LEARN much faster than the Fitech did. Top 10 Holley Sniper EFI Tech Tips Holley Technical Training Manager Tom Kise's top ten "suggestions" for Holley Sniper EFI System installation issues. the motor has the following mods, Aluminum heads, Performer intake, Sniper and MSD ignition module. Marc, you don't mention which system you installed but the Holley systems are fully configurable. No, use only one 02 sensor, mounted close to exhaust manifold, or high up on a Header collector, not into a single Header pipe that merely gets a exhaust pulsation. You'll also notice that the firing order is 1-6-5-4-3-2. Got a picture? Once the tune is complete, the O2 sensor can be defeated or . EFI EFI kit electronic fuel injection. Your talking flames at that point, and it will definitely have an effect on the reading. Its the Holley Pro Jection TBI mentioned by the above poster. I had questions on the suggested "Marine O2 Sensor Adapter" from Howell EFI (https://howellefi.com/product/adaptor-o2-sensor-for-marine-use/), but when I look to the pictures, I understand how it will work. Staff Writer. Top 10 Holley Sniper EFI Tech Tips Holley Technical Training Manager Tom Kise's top ten "suggestions" for Holley Sniper EFI System installation issues. Each engine has the Holley marine 2 barrel carburetor. I'm 3" down from the bottom of the flange to center of bung. THen you have to determine if you want 02 readings from one cylinder, or in the case you just mentioned mostly one cylinder, average of 4 cylinders on one bank or the other, or average of all 8 cylinders. It works fine. Holley EFI requires several pressure inputs in order to run an engine. For the most part, the small harness is plug-and-play. 4. . It looks like another season has come and passed by without the answer you wanted on this.I am impressed that you made the leap into marine fuel injection but you have experienced the same problem that everyone else who has tried this has faced. Sensors that are installed in an exhaust must be connected to a properly functioning controller during engine operation Additionally, if an Sniper or Terminator X EFI System has repeated O2 sensor failures and none of the above-listed suggestions seem likely then contact Holley and arrange to have the unit tested. Menu. They are the only ones got me a holley usb to can cable fast. Does an yone have a pic of the O2 sensor in their exhaust? If you are using our Services via a browser you can restrict, block or remove cookies through your web browser settings. You will need an O2 sensor to measure fuel needs, but it could be tuned manually like in the old days. Some logs have water up to just short of the port. With over the transoms you might get away with it if the water is introduced at the very very end, and the O2 is mounted right at the log. Capability Range: Professional My Lightnings have a bung welded through the water and into the dry exhaust area at the collector. 10 min read. Holley Sniper EFI Wideband Oxygen Sensor Part Number: 510-554-155 Click image to zoom $125.99 More than 10 available Lowest Price Guarantee Sniper EFI Wideband Oxygen Sensor Replacement Part for Holley Sniper EFI and Terminator X Systems Bosch LSU 4.9 See more product details Free Shipping - Ships Today QTY Add To Cart Add to Wish List The Sniper needs a "clean" 12V wire that is hot in Start and Run. Taipei has dozens of world-class restaurants where gourmets can sample the most authentic Chinese cuisines. If there's anyone willing to read a bit and offer advice about what to do when doing a top-end swap (when you may be in a scenario with a new top-end that's the EFI isn't calibrated for AND you can't have an WBO2 sensor connected), please let me know. Hopefully this one lasts longer than the original. But it is going to be a little tricky. This is great information that can only get you closer to an ideal solution. Good luck! Im almost at your exact same setup on a Redline 460/Berkeley pump but waiting to pull the trigger on the Sniper until I can pinpoint exactly where I can install the o2 sensor without the wet exhaust damaging it. I recognize that it would be an absolutely tremendous investment, but based on the overwhelming response we get to this post I am pretty confident that the market is there. If you've done some automotive fuel map tuning before, you can likely overcome this challenge. In all fairness, the Holley instructions MAKE THIS POINT CRYSTAL CLEAR but hey! Pricing was reasonable, shipping was prompt and Chris helped me with a wiring question during my install. I didn't read all this, but yes, the EFI system can be run without a WBO2 sensor. May 19, 2021. They are about 4 inches long, in-line between the log and manifold. the Hamilton 212 pump is maxed out at about 4600 rpms, however it will provide about 10x the thrust that the berkly it is not as fast but haul much more load and work way better in white water. This boat has a non-vortech motor with a 2 bbl gm intake i'll need to replace. Once you have those points set, the rest of the map doesn't really matter, just make it look smooth/pretty and everything will be fine. You shouldn't feel too bad about that lack of knowledge, because many boat owners either don't realize that the moisture present in their wet exhaust manifold will kill the wideband O2 sensor required by an EFI system. Below are the most common sensor usages in a Holley EFI system, however pressure transducers can be applied to any form of pressure in an automotive system, from oil pressure, to exhaust back pressure, and the data gathering usages in racing can get quite creative. #3. Boats don't cruise at 60mph up and down hills. Anyone have a good place to find a genuine Bosch O2 replacement sensor without paying $110? Price Point: $$$. PRO's: Wideband O2 sensor harness is longer, allowing easier connection and routing. The wide band O2 sensor is required for initial running and calibration. Specs. The following vehicles are considered Racing Use Only Vehicles: Holley is the new standard in EFI! Do you also recognize that the O2 sensor that is required for closed-loop operation will not survive in the "wet" manifold used by most marine engines, and that to install a device to protect the O2 sensor from this moisture may require the removal, machining, and replacement of the exhaust manifold? View Holley Sniper EFI Self-Tuning Kit - Shiny Finish. Fine tuned the timing to 12-15 degrees. Distributor and ignition box? It appears that its a tuning issue. The light shines in the darkness, and the darkness has not overcome it. Are you running the entire system? What I think a lot of folks are missing is correct tuning of their carburetor engines Most inboard systems I worked on were intentionally set up to run rich with minimal timing (mostly to get through the warranty period). Supports up to 650hp with Four 100 Lb/Hr Injectors! Holley EFI Oxygen Sensor. 5. OP, the Edelbrock system looks to use the same basic sensors as the Holley sniper system: TPS, MAP and O2, plus a few supporting sensors. As a follow up, I ended up using an eBay type anti fouler elbow for the O2 sensor to try and get it out of the water in the manifolds. The fuel module is self contained with water jacket cooling and contains the low and high pressure pumps. 2023 HOLLEY PERFORMANCE PRODUCTS, INC. ALL RIGHTS RESERVED. You need to intimately know the system you are using, its capabilities and limitations, install it correctly and have it tuned with someone with experience specific to marine applications. Stock manifolds? John 1:5, 1969 FJ40 2F with Holley Sniper EFI, Power Disk Brakes Front & Rear, Downey, Your post has peaked my curiosity. No one cares about your buddies old antiquated garden hose technology. Staff Writer. On my system, I machined in the O2 sensor right between the snail and the manifold of a . I tried holley tech support, no answer and put on hold for hours. Emissions. Let him re-jet the carb (a wee bit on the fat side for safety) and reset the timing and try again. And the relay and fuse were mounted along the firewall. I mounted it here attempting to protect it from the deep water I play in and from lots of branches I encounter. - Do you know of a Carburetor Builder who has addressed the Coast Guard certification issues with the Sniper EFI? Initial Calibration in Basic Configuration. He had one there that was run on a dyno then the fuel map was set and shipped back. Holley EFI Oxygen Sensor. Brand: Holley EFI Emission Code: 5: Material: . Using the throttle body's fuel pressure regulator will require a 5/16" fuel return line to the tank. As far as spark control, the Sniper will let you tune those 4 points, nothing else will. Much of the system is encased right inside the throttle bodyand that includes the ECU. Price Point: $, Advanced throttle body injection systems capable of transmission control and more. Plug into the coolant temperature sensor. Holley Sniper EFI Self-Tuning Kit - Black Ceramic Finish. All I can say is it made a completely different motor out of the 460, 39 degrees out and starts within 2 revolutions power is super smooth throughout the rpm range (idle to 4100rpms 212 Hamilton with 4.0 turbo impeller) has about 6 hrs of learn time. 29. They have been working out well for a few years now. The other thing I want to overcome is the fuel return line; my harbor master says that I can connect my fuel return line to my CAV (lucas) gasoline filter, it has 4 connection, now only 2 are used. Maybe going all the way to the front is the way to go? I only have a stick welder and didn't trust myself on the thin pipe so I brazed it in. Get fast, Free Standard Shipping on orders over Summit Racing Equipment from $99 -- no shipping, handling, or rural fees! However, advanced tuning software is available for the Sniper EFI System that allow them to be tuned by a competent professional with experience tuning marine applications. Given the traditionally poor fuel economy of carbureted marine engines, we feel your pain. Categories. For gourmands, night markets not only offer scrumptious small . I will keep the replacements as spares. The ones in the Bosch box come without warranty. Make sure to put anti seize on the threads. I'm guessing by snail, that's another name for the riser? You should then have at least 18-24" of pipe after the sensor. We also use content and scripts from third parties that may use tracking technologies. Add To Cart. The ones in the Bosch box come without warranty. RPM going up and down , miss firing and backfiring. Come join the discussion about offshore racing, performance, modifications, builds, classifieds, troubleshooting, maintenance, and more! Racing Use Only Vehicles are vehicles that are used exclusively for competition that are not registered and that may never be used on the street. I would prefer to run this brand new Holley EFI system in a closed loop, not set the fuel map, and use the O2 sensor as only a sensor. Fuel economy went from 12.5 to 13.5 gph to 10 gph. No worse than taking the reading in the intake manifold cross over. I think I could run more boost but it's a real hand full right now. Was told by holley tech support to make adjustments to the fuel prime percent and multiplier settings, played with those with no major improvement. Bosch 17025 Oxygen Sensor #1 Best Seller . Late to the party but here's where mine are installed. Oops, after that it cranked right up.Idle was set to 950rpm so after the vid was cut off I lowered it to 820rpm and it was purring like a kitten.EFI for dummies. I'll let you know how it works out. #1. When problem-solving this type of issue, consider when and how you could use a work-around. Option 1 is to purchase and install one of the Holley EFI Dual-Sync Distributors on your engine. PS, Once someone has a good 270/350 tune, everyone can use it. It turns out that this is a common problem with the Sniper EFI install on vehicles with a manual transmission. In the end I ended up using a Fuel Control cell made by Pleasure Craft Marine for their 351W engines. I hope that the next F/2F header is more O2 sensor friendly. pull the sensor out of the exhaust. The original Holley Sniper instructions are available on the Holley website if you have misplaced them. Sorry for the late reply, Douglas. Or maybe I could just use a piece of spare/junk exhaust tubing, and bolt it to the manifolds and add a weldless O2 bung to it. Ref: https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/I heard of the new Sniper EFI from some chatter on OffshoreOnly.com. $132.95. While those work great on an automobile, you likely won't begin to get these marine installations setup with a handheld. Oxygen Sensor is sold separately.Adaptor should be installed in a flat area of riser at least 6 before water blends with exhaust. One comes in the form of a Marine O2 Sensor Adapter from the folks at Howell EFI. Thanks guys. Don't know about HP increase, with the QFT 750 it would turn a 212/4.0 combo to about 3950 to 4000, the Sniper turns it to 4000 to 4100. Register now for free!) The latest is the new Holley Sniper EFI touted as a true bolt-on self-learning carb replacement. so far so good love the smooth power and easy starts. Capability Range: Advanced You must log in or register to reply here. What I don't want to do is spend more money on the headers than on the fuel injection upgrade and new propeller set. Those "flames" are still consuming O2 that would otherwise not be read by a sensor in the correct location. As far as a sensor goes, absolutely nothing. If the indicator reads "LOW Err" double check the connection to the CTS. Add to Cart . The problem is with the Holley computer when you turn on the keyit squirts a prime for a split second. So please, If you have problems registering or can't log into your account, please. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. A 90-degree V-6 has three shared crankpins set 120 degrees apart. Runs like a champ now. Doesn't look like it will have an O2 sensor. There was a 1.5 point difference in afr between banks. Stay up to date with the latest releases, events, promotions and more. Followed all the instructions to the letter. Capability Range: Advanced This was for MPFI. Adam. . I stopped by Bergeron on my way back to the lake, and he said they have never found a good way to run O2 sensors in a marine exhaust. Sniper EFI Quadrajet Marine. I just discovered that was the case with my Fitech. Removed all the unused wires from harness and wrapped all the remaining wires and harness with rfi shielding tape. Do you recommend in-tank or external fuel pump? Items 1 - 21 of 21 Items. 2014 FJ Cruiser - White - 4X4 - Loaded - . Install the throttle linkage to the Sniper EFI throttle body. I did--- Save your money and piece a fuel it together. Use a return fuel line. Waiting for spring to put back together. I purchased the Holley HP MPFI system and went to the lake with it. Then dialed back the cranking fuel quite a bit and that seemed to help some, but still having ongoing issues. O2 sensors are water proof. What is your fuel pressure at the carb during crank? Enter The 2023 LS Fest West Trip Sweepstakes Today And Join Us In Las Vegas! Then if you are do you just wire the o2 sensors in parallel or do these EFI kits have inputs for more than one sensor. . Your BluePrint Engine will be equipped with a Holley model 550-510, or 550-511 (identical except for finish color) on 4150 flanged intake manifolds. The bottom line is that trying to run EFI on a marine engine is not something you can do as an afterthought. Add to Cart . This fixed the high throttle position sensor reading (TPS) of above 1% that likely caused my idle issues. I do agree if he can get it tuned prior to fouling he can lock that tune and run in open loop. He also explains how to properly install them. . Note, that is not a crack in the exhaust manifold, just a shadow from a casting flaw. It is the ratio between the mass of air and the mass of fuel in the air-fuel mix at any given moment. Spray a rag down pretty good with brake cleaner.