Driving me crazy
09-26-2009, 07:30 PM
#1
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Driving me crazy I have done a search before anyone asks. When I try to maintain a constant speed car starts bogging almost like its pulsing and the exhaust note changes. Idles fine and as soon as you give it a little gas it clears up. I'm not throwing any codes. Recent things done are changed spark plugs but have triple checked them and the wires. Spark plugs are NGK tr55 just like before. Seems to only do it after car is at operating temp and has been driven a little. Any ideas maybe fuel pump?
09-26-2009, 08:44 PM
#2
Could be a few things.
failing 02 sensors will do that..and you WILL NOT always get an SES light or code until they totally fail. Scan can show you how they're switching, but you'll need an OBDII liike the dealers use to see that while the engine is running at operating temp.
Dirty/clogged fuel filter and/or fuel injectors can make you sputter or bog while at low rpms, idling or maybe even crusing steady. But when you give it gas the clog should be overcome and it should run fine.
If this started right after you did those new plugs and wires.....it could be from a spark plug wire touching an exhaust manifold pipe. That can cause misfires, but you should get an SES light for those. Bit our PCM's are all not equal...some do things that the next guys will or will not do.
Are your plug gaps within a range of .040 - .060....thats where they should be. .050 is perfect.
Dirty MAF
Crank Shaft Position sensor...when they begin to act up that cause power loss issues. And you will NOT get an SES light until its real bad, where the engine keeps shutting off and its hard to start.
All I got for now.
.
failing 02 sensors will do that..and you WILL NOT always get an SES light or code until they totally fail. Scan can show you how they're switching, but you'll need an OBDII liike the dealers use to see that while the engine is running at operating temp.
Dirty/clogged fuel filter and/or fuel injectors can make you sputter or bog while at low rpms, idling or maybe even crusing steady. But when you give it gas the clog should be overcome and it should run fine.
If this started right after you did those new plugs and wires.....it could be from a spark plug wire touching an exhaust manifold pipe. That can cause misfires, but you should get an SES light for those. Bit our PCM's are all not equal...some do things that the next guys will or will not do.
Are your plug gaps within a range of .040 - .060....thats where they should be. .050 is perfect.
Dirty MAF
Crank Shaft Position sensor...when they begin to act up that cause power loss issues. And you will NOT get an SES light until its real bad, where the engine keeps shutting off and its hard to start.
All I got for now.
.
