Running real rough at idle
03-20-2010, 03:24 AM
#1
TroublemakrExtraordinaire
Thread Starter
Running real rough at idle
I am running an '08 AT Turboed (using Cobb AP for management). I have run out of gas twice in the car and it is a real bitch to get it going again. The second time was last week and it has not run right since. After working the fuel through the system the car is drivable but has serious problems at idle. The idle is real rough and if the car is in gear it wants to engage even at idle RPMs. Once I get over 1.5-2k RPM it runs ok but still not as smooth as before.
I did a complete spark plug swap (using same part numbers as the ones I had in it). The leading/trailing plugs on front cylinder and the leading one on the rear were a little brown. The trailing rear plug was black. I also noticed that the rear O2 sensor plug melted together with the harness side. I have cleaned up the wiring and it never threw any CELs (other than a P0411 due to cold air injection system being removed).
I did a compression test and am getting 110 on the front and 95 on the rear. It was at 90 till I got it running a bit better (which maybe cleared some carbon out).
At this point I am not quite sure where to go. I am thinking that it might be a clogged injector. My diagnostic tools are severely limited as is my experiance working on a rotary engine. Does anyone have suggestions on where to start looking?
I will happily provide any useful information requested.
I did a complete spark plug swap (using same part numbers as the ones I had in it). The leading/trailing plugs on front cylinder and the leading one on the rear were a little brown. The trailing rear plug was black. I also noticed that the rear O2 sensor plug melted together with the harness side. I have cleaned up the wiring and it never threw any CELs (other than a P0411 due to cold air injection system being removed).
I did a compression test and am getting 110 on the front and 95 on the rear. It was at 90 till I got it running a bit better (which maybe cleared some carbon out).
At this point I am not quite sure where to go. I am thinking that it might be a clogged injector. My diagnostic tools are severely limited as is my experiance working on a rotary engine. Does anyone have suggestions on where to start looking?
I will happily provide any useful information requested.
03-20-2010, 11:10 AM
#3
TroublemakrExtraordinaire
Thread Starter
According to Cobb, MAF is about 14.7ish. Not sure on the throttle body but not feeling/seeing any leaks.
I think down to 90 is technically in spec for compression but I agree that below 100 is a bit weak.
I think down to 90 is technically in spec for compression but I agree that below 100 is a bit weak.
03-20-2010, 11:54 AM
#4
Put in a can of HEAT.
You may have a little water in the line. Also, put in Lucas fuel injector cleaner.
See if it works better.
You can check the TB. Under there is a cap. Make sure it is on and not leaking.
You can try to resetting the ECU but I don't think that will help.
Are you going to bring a small keg next week to the Dyno session?
You may have a little water in the line. Also, put in Lucas fuel injector cleaner.
See if it works better.
You can check the TB. Under there is a cap. Make sure it is on and not leaking.
You can try to resetting the ECU but I don't think that will help.
Are you going to bring a small keg next week to the Dyno session?
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