Car suddenly started running really rich yesterday..
#1
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Car suddenly started running really rich yesterday..
Yesterday I was on my way home from work - On the highway going about 65 (not in boost at all) and the car just seemed to be running a bit strange (like it was missing or something) Sputtery is how I would explain it in one word. I did notice a heavy gas smell (like a lawnmower) kept driving for about a mile and took the next exit. Just as a test I did try to build boost. I didn't get into boost but I did feel like the car would have got into boost if I would have pushed it. When I got off at the exit the car was pouring greyish smoke. Checked my AF gauge and the car was running extremely rich. Drove the car another 2 miles to my house and parked it. It was still pouring smoke. I stopped the car unplugged the battery (thought of resteting the ECU) plugged it back in and tried to start. It wont start now.
The car was not overheating at all - all gauges seemed right EXCEPT air fuel.
Strange thing is a few times when I first started the car in the past few weeks the car has ran like this for 10 seconds when I first started the car. But after that no issues.
The car is a TN kit with a well tuned UTEC with 550CC injectors and AAM Fuel return setup.
I have built all my own cars in the past so it made it easier to work on. But this car I really know nothing about since I really haven't done any of the work myself.
My tech that built the car is about 100 miles away so not sure if I want to take it their until I am sure its not something simple first.
Anyone got any simple possible solutions. I realize that its not something that can be diagnosed over the internet but any ideas would help. I really hate this car sometimes.
The car was not overheating at all - all gauges seemed right EXCEPT air fuel.
Strange thing is a few times when I first started the car in the past few weeks the car has ran like this for 10 seconds when I first started the car. But after that no issues.
The car is a TN kit with a well tuned UTEC with 550CC injectors and AAM Fuel return setup.
I have built all my own cars in the past so it made it easier to work on. But this car I really know nothing about since I really haven't done any of the work myself.
My tech that built the car is about 100 miles away so not sure if I want to take it their until I am sure its not something simple first.
Anyone got any simple possible solutions. I realize that its not something that can be diagnosed over the internet but any ideas would help. I really hate this car sometimes.
Last edited by mpcstuff; 04-11-2010 at 02:45 PM.
#4
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You still have a MAF in there? I have had my MAF cause such issue, it would run rich to the point it almost stalled, a/f in the low 9s at idle. (after cleaning it, it stop giving me problems)
Also, perhaps an injector is stuck open for some reason..
Those are a couple of possibilities.
Also, perhaps an injector is stuck open for some reason..
Those are a couple of possibilities.
#6
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You still have a MAF in there? I have had my MAF cause such issue, it would run rich to the point it almost stalled, a/f in the low 9s at idle. (after cleaning it, it stop giving me problems)
Also, perhaps an injector is stuck open for some reason..
Those are a couple of possibilities.
Also, perhaps an injector is stuck open for some reason..
Those are a couple of possibilities.
I had this exact issue as well 2 years ago, the car was billowing smoke so bad it was filling the street.
Car was stuttering, and just ran like **** after being boosted for some time.
Cleaned the MAF, issue never returned.
#7
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Can you hook up your laptop to the UTEC and see what all of your sensors are reading? It's feasible that your UTEC MAP sensor got wet and is giving false readings. If the UTEC thinks you are boosting you will be running in open loop and you would b very rich!
If you can look at the UTEC dashboard with hyperterminal you can see if the sensor is reading correctly - with the engine off is should read 0 psi.
If you can look at the UTEC dashboard with hyperterminal you can see if the sensor is reading correctly - with the engine off is should read 0 psi.
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#12
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my setup has been runnign really rich under boost. I haven't messed with my tune in a couple years, and everything has been fine. now, when I go into boost , it gets really rich...sometimes in the 9:1 range! but under normal driving, everything's fine. I guess I need to pull out the laptop and do some datalogging and see if anything is showing up there.
I have already checked my plugs and run a compression test.....everything looked fine there.
I have already checked my plugs and run a compression test.....everything looked fine there.
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So took out the MAF cleaned it up with the MAF cleaner. Put it back in still same problem car wont start. I couldnt be so lucky with this car.
I do have the UTEC map so I checked it and all connections close to it. Didn't seem to have any problems.
I also searched around for any visible vacuum line problems. Did not see anything.
ANy more info on how I would check to see if somehow the UTEC lost its program?
I do have the UTEC map so I checked it and all connections close to it. Didn't seem to have any problems.
I also searched around for any visible vacuum line problems. Did not see anything.
ANy more info on how I would check to see if somehow the UTEC lost its program?
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I had similar issue last week. Took off the MAF to clean and it ran 1/2 day without any issue. Then it came back again. Took it out again and reinstall it then it went off. Next morning when I start my car it went rich again. I don't get this problem anymore for a week now with a new MAF replacement.
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check your fuel pressure on your regulator. It sounds like your return line is clogged.
I just had this issue last week. i was 12:1 on the highway cruising and the car was driving like crap. I checked my fuel pressure and it was 100psi! The diaphragm in the regulator broke and pieces of it went back and clogged my twin pump.
If your fuel pressure is high then something is clogging the return line or the regulator is having an issue. I would take the reg apart and check the diaphragm first. If that looks ok then i would remove your return line and turn the fuel pump on and see if it flows ok. you might have to take the basket out and check that return correction piece to seeif something got in there and clogged those little pores.
I just had this issue last week. i was 12:1 on the highway cruising and the car was driving like crap. I checked my fuel pressure and it was 100psi! The diaphragm in the regulator broke and pieces of it went back and clogged my twin pump.
If your fuel pressure is high then something is clogging the return line or the regulator is having an issue. I would take the reg apart and check the diaphragm first. If that looks ok then i would remove your return line and turn the fuel pump on and see if it flows ok. you might have to take the basket out and check that return correction piece to seeif something got in there and clogged those little pores.