TurboedMJ Posted June 30, 2023 Share Posted June 30, 2023 My truck is running way too rich at idle. To the point where fuel is spraying out of the exhaust pipe. Recently replaced within the last 2k miles: - plugs, wires, distributor, injectors (Amazon 4 hole cheapos), IAC, fuel pump, O2 sensor. Completed tips 1-5 from cruiser. Any tips/suggestions? Link to comment Share on other sites More sharing options...
Ωhm Posted June 30, 2023 Share Posted June 30, 2023 Check the Fuel Pressure Regulator (FPR) vacuum hose between the FPR and intake manifold for fuel in the hose. Link to comment Share on other sites More sharing options...
TurboedMJ Posted June 30, 2023 Author Share Posted June 30, 2023 There should be fuel in it while it's off correct? Or should I switch the ignition to run the fuel pump for a minute Link to comment Share on other sites More sharing options...
cruiser54 Posted June 30, 2023 Share Posted June 30, 2023 Cheapo Amazon injectors or faulty MAP sensor and/or the line to the MAP. If at idle only, most likely the injectors. Good chance the MAP tubing got messed up during injector installation. There is a fellow Jeeper who supplies the correct, refurbished, and TESTED injectors for this community. Only place to get them IMHO. Link to comment Share on other sites More sharing options...
cruiser54 Posted June 30, 2023 Share Posted June 30, 2023 CRUISER'S MOSTLY RENIX TIPS THROTTLE BODY TO MAP SENSOR HOSE FIX JANUARY 23, 2016 CRUISER54 51 COMMENTS The Renix throttle bodies have a strange and failure prone connector on the side where the MAP supply originates and then runs up to the MAP sensor located on the firewall. This hose/pipe assembly is no longer available for purchase. The real kicker here is how critical this line is in supplying the correct vacuum signal to the MAP, the most relied upon sensor for the ECU to read regarding air/fuel ratio. Any cracks, melted spots, or loose rubber connectors can cause major starting and driveability issues. There’s a simple fix though. All that’s required is a 1/8” NPT tap, a new throttle body gasket ( Napa FPG 60742 ), a vacuum fitting (Napa 05703-B102), two vacuum elbows (Napa CRB2670), and a length of new plastic piping (Napa CRB2672). Remove the throttle body and take it to the workbench. Using an oiled tap along with a driver, carefully thread the lower of the 2 holes of the throttle body where the old fitting was plugged in. Don’t go too deep. These are pipe threads. Flush the hole with carb cleaner and inspect for any left over cuttings. This is an excellent time to do a complete throttle body and IAC cleaning. See Tip 11. Take the vacuum fitting (05703-B102 ) and apply a LITTLE bit of thread sealer on the threads only. I prefer Permatex #2 but almost anything is fine. . Carefully screw the fitting in until snug. Install one of the vacuum elbows on the MAP sensor so it points toward the throttle body, and the other vacuum elbow on your new throttle body fitting so it points up to the MAP sensor. Cut a length of the new plastic tubing (approximately 13 inches) to fit between the vacuum elbows and install it making sure there is enough slack for some engine movement. Route it according to the photo. We don’t want any rubbing or chafing with engine movement. Not a bad idea to use some contact cement or Gasga-Cinch sparingly on the tubing to elbow connectors. Link to comment Share on other sites More sharing options...
Ωhm Posted June 30, 2023 Share Posted June 30, 2023 10 hours ago, TurboedMJ said: There should be fuel in it while it's off correct? Or should I switch the ignition to run the fuel pump for a minute KEY ON/OFF, you never want fuel in this vacuum line. Fuel would indicate leaky FPR. Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 12 hours ago, cruiser54 said: Cheapo Amazon injectors or faulty MAP sensor and/or the line to the MAP. If at idle only, most likely the injectors. Good chance the MAP tubing got messed up during injector installation. There is a fellow Jeeper who supplies the correct, refurbished, and TESTED injectors for this community. Only place to get them IMHO. I have an HO throttle body, intake manifold, and head. I believe this is my MAP hose? Who does the injectors for the 4.0? Where can I get them? Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 11 hours ago, Ωhm said: KEY ON/OFF, you never want fuel in this vacuum line. Fuel would indicate leaky FPR. There is no fuel in the hose when off, or after the fuel pump has pressurized Link to comment Share on other sites More sharing options...
Ωhm Posted July 1, 2023 Share Posted July 1, 2023 Does that MAP hose have something "T" into it? Thats not normal. Follow vacuum hose from MAP to intake manifold just to make sure its right. Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 7 minutes ago, Ωhm said: Does that MAP hose have something "T" into it? Thats not normal. Follow vacuum hose from MAP to intake manifold just to make sure its right. Nevermind, this is the actual map hose. It goes right to the sensor. Link to comment Share on other sites More sharing options...
Ωhm Posted July 1, 2023 Share Posted July 1, 2023 Looks like your running the HO TPS. Wiring might be different between the HO and RENIX. Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 Terminal C of the map plug reads 5.03. terminal B reads 17.4??? Tested with two different multi meters. Any suggestions. Link to comment Share on other sites More sharing options...
Ωhm Posted July 1, 2023 Share Posted July 1, 2023 Don't understand 17.4 reading. Never done a HO vs RENIX TPS comparison before. Maybe someone on site has. Note the two pages I've included for you. TPS RENIX.pdf TPS HO.pdf Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 14 minutes ago, Ωhm said: Don't understand 17.4 reading. Never done a HO vs RENIX TPS comparison before. Maybe someone on site has. Note the two pages I've included for you. TPS RENIX.pdf TPS HO.pdf I'm not working on the TPS. those readings were from the plug that plugs into the MAP sensor Link to comment Share on other sites More sharing options...
Ωhm Posted July 1, 2023 Share Posted July 1, 2023 Yea I missed that. Still 17.4 anywhere is not normal for a 5vdc circuit. I think your running rich may be caused by the TPS. Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 1 minute ago, Ωhm said: Yea I missed that. Still 17.4 anywhere is not normal for a 5vdc circuit. I think your running rich may be caused by the TPS. I did the test again using a different method and terminal C read 5.02 and terminal B read 4.74. is that within an acceptable range? Link to comment Share on other sites More sharing options...
Ωhm Posted July 1, 2023 Share Posted July 1, 2023 Yes. If you're back probing the MAP connector (connector still connected to MAP), readings look good. Link to comment Share on other sites More sharing options...
cruiser54 Posted July 1, 2023 Share Posted July 1, 2023 HO and Renix TPSs work opposite of each other. The Renix system will not work with an HO TPS. Link to comment Share on other sites More sharing options...
cruiser54 Posted July 1, 2023 Share Posted July 1, 2023 Injectors: trevor.skankfootracing@gmail.com Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 8 minutes ago, cruiser54 said: Injectors: trevor.skankfootracing@gmail.com Thanks 10 minutes ago, cruiser54 said: HO and Renix TPSs work opposite of each other. The Renix system will not work with an HO TPS. Previous owner set it all up. Not sure how the system works together but it seems to 🤷🏼♂️ Link to comment Share on other sites More sharing options...
cruiser54 Posted July 1, 2023 Share Posted July 1, 2023 Doesn't seem like it works well to me. Voltage to the ECU from one TPS goes up as the throttle opens and the voltage goes down on the other as the throttle opens. Tell me how that can work properly. Backwards. You need a Renix TPS adapted to the HO throttle body, or just get a Renix intake and throttle body. That HO intake and throttle body are not worth keeping. Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 16 hours ago, cruiser54 said: Doesn't seem like it works well to me. Voltage to the ECU from one TPS goes up as the throttle opens and the voltage goes down on the other as the throttle opens. Tell me how that can work properly. Backwards. You need a Renix TPS adapted to the HO throttle body, or just get a Renix intake and throttle body. That HO intake and throttle body are not worth keeping. Is it possible that whoever set this up intentionally wired it backwards? When I pull the wiring out of the split loom I find this Link to comment Share on other sites More sharing options...
TurboedMJ Posted July 1, 2023 Author Share Posted July 1, 2023 On 6/29/2023 at 6:48 PM, TurboedMJ said: To the point where fuel is spraying out of the exhaust pipe I was able to get a sample and smell it, it's actually just water vapor. I still believe it's running rich tho Link to comment Share on other sites More sharing options...
Ωhm Posted July 1, 2023 Share Posted July 1, 2023 In the photo, looking down on the TPS connector, is it labeled as the following: C B A Link to comment Share on other sites More sharing options...
cruiser54 Posted July 1, 2023 Share Posted July 1, 2023 No matter how it's wired, the sensors work opposite of each other. Link to comment Share on other sites More sharing options...
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