Rough Running HELP! Please...
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Joined: Feb 2008
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Rough Running HELP! Please...
For myself & my mechanic this has become a difficult trouble to track down.
'92 LT1 automatic 107k miles. Only mods, no mufflers & top off air breather. Replaced ECM 2 yrs. ago, plugs & wires 2 mo ago, tranny service 2+ yrs ago. Regular diet of 90 octane (no ethanol)
When driving on slight incline as tranny comes out of lock-up @ 40+/- mph seems to slip some, then engine runs very rough, bogs down, backfires slightly, & pinging. Moderate to strong acceleration & tranny downshifts & engine runs fine. Seems to be getting worse & more frequent.
No codes set. Mechanic thinks timing not advancing as it should.
Where to go from here?
In advance THANK YOU for feedback...
'92 LT1 automatic 107k miles. Only mods, no mufflers & top off air breather. Replaced ECM 2 yrs. ago, plugs & wires 2 mo ago, tranny service 2+ yrs ago. Regular diet of 90 octane (no ethanol)
When driving on slight incline as tranny comes out of lock-up @ 40+/- mph seems to slip some, then engine runs very rough, bogs down, backfires slightly, & pinging. Moderate to strong acceleration & tranny downshifts & engine runs fine. Seems to be getting worse & more frequent.
No codes set. Mechanic thinks timing not advancing as it should.
Where to go from here?
In advance THANK YOU for feedback...
Instructor
Joined: Dec 2011
Posts: 136
Likes: 3
From: pittsburgh pa.
not sure if this applies to your vette, i had a buick which had a vacuum controlled modulator valve for tranny. maybe start with that. vacuum loss = rough running. note; maybe move your post to tech for advice
Last edited by chrldo; Oct 21, 2012 at 02:15 PM. Reason: note
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Joined: Feb 2008
Posts: 92
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Thanks for moving my thread over here.
Fuel filter has less than 10k miles on it.
As this condition occurs, the sputtering, missing, backfiring, pressing to WOT alleviates everything.
Don't think it'd be fuel related if that's the case???
Second mechanic (transmission specialist) looked at it Friday, & their consensus is now the distributor / opti-spark.
But still nothing definitive...
Appreciate any insight...
Fuel filter has less than 10k miles on it.
As this condition occurs, the sputtering, missing, backfiring, pressing to WOT alleviates everything.
Don't think it'd be fuel related if that's the case???
Second mechanic (transmission specialist) looked at it Friday, & their consensus is now the distributor / opti-spark.
But still nothing definitive...
Appreciate any insight...
