1992 MTX, 124K miles. This is the one that I just fixed the doors one.
The car stumbles at the bottom of the rev range. By stumble, I mean it seems like someone clamped the gas or air off. It pops some mini backfires out, and works fine at higher RPMS when you finally nurse it up there.
SO, I changes the plugs, wires, fuel filter air filter, thinking it was just in dire need of some basic tuning up. The plug wells were so full of oil, that when I took the plug wire out, it splashed all over, it was so bad it was actually runnign out the top of the holes, they were completely full. I figured I had found the culprit, and completed the job. I was the FIRST person to ever do this in this car, those wires or plugs *** never been changed, and that intake had NEVER been off. All shim clearances were in spec, and the inside was pretty darned clean, the oil was still clear-ish, no black mung or anything. NO wear marks on the cam lobes or anything.
So, got it all back together, fired right up, still has the stumbling problem. When you throttle up by hand, turning the throttle up at the throttle, it just sounds like it's being cut off of gas or air, and sputters, barely keeps running, then when you let go of the throttle, the revs snap right back up to high revs and normally comes down to idle. I checked to make sure the secondaries were closing when started, and they are engaging as expected when the car starts, all plugs are in the correct firing order, gapped correctly, new wires. This car has no EGR either. NO CODES!.
It idles fine, so pretty much from idle to about 2200, just stumbles, sputters, barely gets up to 2200, then it's fine and dandy above that RPM..
Any thoughts? I was going to swap out the y-pipe to see if maybe it was clogged/bad and see if that helped. I would think it would be worse at the top, than the bottom though, if it was the y pipe. Same with the fuel pump, I would think it would do worse at higher RPMs than lower..
N
<small>[ September 02, 2003, 09:05 AM: Message edited by: Nook ]</small>
The car stumbles at the bottom of the rev range. By stumble, I mean it seems like someone clamped the gas or air off. It pops some mini backfires out, and works fine at higher RPMS when you finally nurse it up there.
SO, I changes the plugs, wires, fuel filter air filter, thinking it was just in dire need of some basic tuning up. The plug wells were so full of oil, that when I took the plug wire out, it splashed all over, it was so bad it was actually runnign out the top of the holes, they were completely full. I figured I had found the culprit, and completed the job. I was the FIRST person to ever do this in this car, those wires or plugs *** never been changed, and that intake had NEVER been off. All shim clearances were in spec, and the inside was pretty darned clean, the oil was still clear-ish, no black mung or anything. NO wear marks on the cam lobes or anything.
So, got it all back together, fired right up, still has the stumbling problem. When you throttle up by hand, turning the throttle up at the throttle, it just sounds like it's being cut off of gas or air, and sputters, barely keeps running, then when you let go of the throttle, the revs snap right back up to high revs and normally comes down to idle. I checked to make sure the secondaries were closing when started, and they are engaging as expected when the car starts, all plugs are in the correct firing order, gapped correctly, new wires. This car has no EGR either. NO CODES!.
It idles fine, so pretty much from idle to about 2200, just stumbles, sputters, barely gets up to 2200, then it's fine and dandy above that RPM..
Any thoughts? I was going to swap out the y-pipe to see if maybe it was clogged/bad and see if that helped. I would think it would be worse at the top, than the bottom though, if it was the y pipe. Same with the fuel pump, I would think it would do worse at higher RPMs than lower..
N
<small>[ September 02, 2003, 09:05 AM: Message edited by: Nook ]</small>
