Hi all,
i have read a few post over rthe forum of MPI engines running rich but none have really helped me with the problem i am having.
Engine gets to operating temp ok but runs rich at idle, leaving a carbon deposit on the water and also blowing black smoke.
I have checked the IAC with scan tool and appears fine, have even gone to the efforts of removing the IAC off the port engine to try as well, it was reset and still the problem remains.
Checked temp coolant temp sender, ok
I then used the scan tool to check all readings at idle and recorded them all, i then connected scan tool to other engine and recorded all information from it as well, both readings read almost identical.
Started to change parts, 1 at a time obviously, coolant temp sender, intake air temp sender, map sensor, swapped dist cap and leads, all made no change.
Swapped ECU, no difference.
then had a thought i may be spark related although there were no symptoms of a missfire or running rough. I used a timing light on the plug leads and found that i was getting an irregular flash on the timing light, only thing was is that it was on all cylinders. Wierd!!
check timing light on other engine and timing light was ok
Removed plugs to find very carboned up so used new plugs, spark came back to normal on timing light and i would think that the plugs were that fouled that they wouldnt ignite the fuel
engine was still running rich though.
Swapped coil, made no difference
only a couple of things to go now i guess, remove and replace moduel in distributor?
remove and get injectors tested?
any help on this one would be greatly appreciated
Jason.
oh and compression test done and all ok at 220psi
i have read a few post over rthe forum of MPI engines running rich but none have really helped me with the problem i am having.
Engine gets to operating temp ok but runs rich at idle, leaving a carbon deposit on the water and also blowing black smoke.
I have checked the IAC with scan tool and appears fine, have even gone to the efforts of removing the IAC off the port engine to try as well, it was reset and still the problem remains.
Checked temp coolant temp sender, ok
I then used the scan tool to check all readings at idle and recorded them all, i then connected scan tool to other engine and recorded all information from it as well, both readings read almost identical.
Started to change parts, 1 at a time obviously, coolant temp sender, intake air temp sender, map sensor, swapped dist cap and leads, all made no change.
Swapped ECU, no difference.
then had a thought i may be spark related although there were no symptoms of a missfire or running rough. I used a timing light on the plug leads and found that i was getting an irregular flash on the timing light, only thing was is that it was on all cylinders. Wierd!!
check timing light on other engine and timing light was ok
Removed plugs to find very carboned up so used new plugs, spark came back to normal on timing light and i would think that the plugs were that fouled that they wouldnt ignite the fuel
engine was still running rich though.
Swapped coil, made no difference
only a couple of things to go now i guess, remove and replace moduel in distributor?
remove and get injectors tested?
any help on this one would be greatly appreciated
Jason.
oh and compression test done and all ok at 220psi
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