kieren1234 Posted April 8, 2008 Share Posted April 8, 2008 Hi all, could someone list the possible things that can cause the car to run rich i.e vaccuum leak etc I know it could turn into a lengthy list i just want to start troubleshooting. Quote Link to comment Share on other sites More sharing options...
mikeyb10supra Posted April 8, 2008 Share Posted April 8, 2008 Check your 02 sensor, also running excessively lean can cause the ECU to overcompensate and run rich....do you have a wideband? Also check temp sensors, if the ECU see's the car as being cold it will run rich Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 8, 2008 Author Share Posted April 8, 2008 The car is an na-t and runs about 9.5 afr's on idle constantly from first start to fully warmed up so you could be right about the temp sensors. Where abouts are they?? Many thanks. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 8, 2008 Author Share Posted April 8, 2008 O2 sensor is brand new too. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 8, 2008 Author Share Posted April 8, 2008 Does anyone know the location of the sensors please??? Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 9, 2008 Author Share Posted April 9, 2008 Update, have changed the coolant temp sensor (one with the two wires) and having the same problem with it running that rich it dies after so long. Anything else i can rule out of the equation?? Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 9, 2008 Author Share Posted April 9, 2008 I have also tried a friends ecu, map sensor, and 2 different known working e-manages but nothing again. I have re wired the e-manage twice but still nothing. The car doesnt change how it runs when i make changes on the e-manage like trimming fuel out or increasing the injector size from 330 - 440. I dont think the problem lies with the injectors or resistor box as it was running pig rich to begin with. I can get it started if i only plug 4 of the injectors in, then when its running plug the other two in. But then just runs majorly rich contantly at about 9.5 afr's on idle. I will gladly send over £50 to whoever sorts the problem as it has caused me so much bloody stress and sleepless nights thinking what it could be :( Quote Link to comment Share on other sites More sharing options...
Ryan.G Posted April 9, 2008 Share Posted April 9, 2008 Ok it sound like all the injectors have a 12v feed going to them so i would suggest checking the 6 injector feeds which go back to the ECU to tell them to open. If one of them is grounding out somewhere then it will be opening that injector 100%. Do a continuety test back from each injector plug to the ecu and it should not have any resistance. If that is fine, Check your Fuel pressure and that the injectors are actually low impendance. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 9, 2008 Author Share Posted April 9, 2008 Hi Ryan. The injectors are from a mkIII Turbo and i have an aftermarket resistor pack. The car was running silly rich before i even installed these so im sure that fitting these was not the problem. Could you elaborate on how i would check that none of the wires are shorting and opening the injector 100% because what you say makes sense why it would be running so rich. Quote Link to comment Share on other sites More sharing options...
TrickTT Posted April 9, 2008 Share Posted April 9, 2008 Does it only run rich on tickover, or under load as well? If its just at idle, check the idle air control valve at the back of the manifold. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 9, 2008 Author Share Posted April 9, 2008 It runs rich throughout the rev range on standstill. When under load it will run rich untill it just begins to come on boost when it beginds to go lean (have not tried WOT or high rpm on boost) Idle is when it runs the richest with about 9.5 afr's. How do i check the iacv without getting a new one?? Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 9, 2008 Author Share Posted April 9, 2008 Bump Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 10, 2008 Author Share Posted April 10, 2008 Ok it sound like all the injectors have a 12v feed going to them so i would suggest checking the 6 injector feeds which go back to the ECU to tell them to open. If one of them is grounding out somewhere then it will be opening that injector 100%. Do a continuety test back from each injector plug to the ecu and it should not have any resistance. If that is fine, Check your Fuel pressure and that the injectors are actually low impendance. Ok, i have checked the resistance AT the ecu by putting one probe of the multimeter on the wire that goes from the injector to the ecu, and the other probe on one of the black/orange wires and each injector measures 1.90 ohms. Im assuming this is wrong. This was all done with ignition turned to ON. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted April 10, 2008 Share Posted April 10, 2008 You need to do the continuity test with the ign off and preferably with loom disconnected first, I'm presuming that the resistance thats showing is from the EMU being in the circuit, however if they all read the same then i guess that rules out a short on one of the wires. The other problem that make it difficult to test is that you have both an emanage (but i think you have now eliminated that by switching for another?) but the wiring still could be wrong, and also the injector resistor pack, and really these should be tested separately, the other problem is that you can't AFAIK electronically test an injector for being stick open. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 10, 2008 Author Share Posted April 10, 2008 Thanks Ricky. I am again, going to re wire the e-manage and check its connections as it still seems wierd that the car does not chenge at all when making changes and exporting it to the main unit. There is definately not a short on one of the injectors as they all show the same resistance. I think the injectors and resistor pack are just adding to the orininal problem of running rich. (was running rich with 330'sa so obviously going to run even richer with the 440's) i am also going to cvheck all the vaccuum pipes with soapy water whilst the car is running, to rule out any vaccuum leaks (allthough im not sure this would make the car run that rich). Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 10, 2008 Author Share Posted April 10, 2008 You need to do the continuity test with the ign off and preferably with loom disconnected first, I'm presuming that the resistance thats showing is from the EMU being in the circuit How do i do this continuity test?? Yes the EMB is in the circuit when i tested the resistance. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted April 10, 2008 Share Posted April 10, 2008 How do i do this continuity test?? Yes the EMB is in the circuit when i tested the resistance. Not quite sure how you have tested already? If you undo the small bolt on the multi connector to the ECU and disconnect from the ECU, you will need a pin out diagram to locate the correct wires, which i,m presuming you already know? and then disconnect the injector plugs and put one meter probe on the appropriate injector plug and the other on the multi connector at the correct wire, and check the resistance, this will at least tell you if there is a short in the wiring. I take it you have checked the injectors to make sure they are high or low impedance type? Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 10, 2008 Author Share Posted April 10, 2008 Not quite sure how you have tested already? If you undo the small bolt on the multi connector to the ECU and disconnect from the ECU, you will need a pin out diagram to locate the correct wires, which i,m presuming you already know? and then disconnect the injector plugs and put one meter probe on the appropriate injector plug and the other on the multi connector at the correct wire, and check the resistance, this will at least tell you if there is a short in the wiring. I take it you have checked the injectors to make sure they are high or low impedance type? So i disconnect the ecu plug that is held in with 10mm bolt. Put one of the the multimeter pins to that end on the loom, and the other multimeter pin to the wire at the injector side?? I will go do that now. The injectors are from mkIII Turbo hence the need for the resistor box to change the impedence. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 10, 2008 Author Share Posted April 10, 2008 Ricky, i have checked the resistance exactly how you said and each get a reading of 0.00 resistance so this is now ruled out of the equation. Perhaps we may be focusing too much on the injectors as it could be a number of different things (what these are i dont know) Help is greatly appreciated so far! Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 10, 2008 Author Share Posted April 10, 2008 Any more ideas folks?? Quote Link to comment Share on other sites More sharing options...
Ian C Posted April 10, 2008 Share Posted April 10, 2008 OK some of this may have been covered already but I'm going to brain dump: 1) Go back to the stock injectors. If you had a running rich problem with those, you were I'm afraid a bit of a fool to stick bigger ones in and hope it all worked Going back to stock rules out it just being the bigger injectors and it rules out issues with the resistor pack. With the smaller ones in you also stand a better chance of diagnosing the problem without turning your engine into a 3.1l block with 2.9l pistons Yes it may be some annoying wiring but this far along the tearing-your-hair-out path it's necessary. 2) It's not going to be a sensor issue with regards to intake temps and water temps - they are trim maps only, there is no way they could get an engine fuelling out of the range of closed loop and then all the way down to 9.5:1afrs. What is the lowest your O2 sensor can read? Is it in fact 9.5:1afrs? Also, does your O2 sensor ever show anything different - e.g. switched on without the engine running it should show a lean value as there is just air in the exhaust (you may need to turn the engine over with the fuel pump disconnected to muck out the exhaust first to test this). Always check your sensors aren't lying to you. 3) I'm sure I asked this before, but can you datalog the stock injector durations with the E-Manage. This is an invaluable tool for diagnosing what the problem is. A warm idle should be about 2.4ms of duration - if it is showing this you have fuel pressure problems, sticking injectors, or an earthing fault thats opening them. Or the impedance is wrong. If the duration is much higher than 2.4 then the ECU is getting something wrong somewhere, a rogue input for example. 4) Check the injectors impedance by measuring the resistance across its terminals. Check the resistor pack impedance by measuring its resistance across the input and one output. You should achieve 12ohms if you add them both together. More than this and youve got a resistor pack when you shouldn't have. 5) Check with the E-Manage what it thinks your MAP sensor is showing. I know this is complicated by the whole MAF/MAP NA to turbo thang but your airflow system still has to work in some fashion. Whatever you are using to tell the STOCK ECU what the airflow into the engine is needs checking. If it isn't wired right or is broken, or it's a MAP sensor with its hose off, you'll probably be sending the ECU an atmospheric signal. As far as the ECU is concerned, that means "full load" to an NA, so the fuelling will be off the clock. 6) Some other things to check quickly with the E-manage monitoring/datalogging: Throttle position RPMs Ignition timing Airflow voltage in vs airflow voltage out vs %age of airflow removed Until you come back with the answers to some of these, especially the readings off the E-Manage, there is no point expanding further See what you get. -Ian Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 10, 2008 Author Share Posted April 10, 2008 Thanks for that Ian. I will get straight onto it tomorrow morning and report back. Many thanks. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 14, 2008 Author Share Posted April 14, 2008 Ian C, i have gone back to the stock injectors and the car now starts everytime but as before, runs pig rich again.] I will be able to check the other things you have mentioned on the weekend. Many thanks. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 14, 2008 Author Share Posted April 14, 2008 Ian C i have been and done some datalogging and hopefully these answers/finings will help you to help me 1. I now have the stock 330's in there and i agree i was silly to put bigger injectors in when i knew it was running rich before (although in my defence i did think the e-manage would be able to trim the extra fuel flow). 2. I had already put in a new coolant temp sensor and like you have said, had no impact on the problem. The car is definately running 9.5 afr's, the wideband will read as low as 7.4. 3. Yes you can log the injectors and here are my findings: On Idle the injectors are 6.7ms of duration: When revving the car to 1000rpm injectors are 13.1ms of duration: 4. I will have to check the impedance once i get my multimeter back from friend this weekend. 5. I ave checked the MAP sensor and the pipe on it is brand new silicone, and the electrical connection is secure. Please see above pics of the input and output of the sensor. 6. Throttle position seems to be ok Rpm coincide with what is displayed on the dash Ignition timing is done by moving the distributor on the N/A and e-manage cannot control this. Airflow equation please see above pics. Quote Link to comment Share on other sites More sharing options...
kieren1234 Posted April 15, 2008 Author Share Posted April 15, 2008 Bump. Quote Link to comment Share on other sites More sharing options...
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