Dubya Tee Ef. Still have hesitation. Help mehhhhh
09-13-2010, 12:56 PM
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Dubya Tee Ef. Still have hesitation. Help mehhhhh
Alright so I haven't posted this one up on here. I did on 944online but I still even after changing many things am getting an intermittent hesitation that I simply cannot explain.
- Feels like when I step on it, it produces what feels like the "same" amount of power. Doesn't feel like it improves. Even if I give it everything. feels worse in 3rd and on... 1st and second it's there but not as bad.
- Sometimes it feels like the power comes on in spurts. It'll be there, then not, then it's there again, then sorta flat.
- Sometimes seems ok and "wakes up" but it's usually later rpms, 3k and on usually.
- Does seem worse when cold. Better when warm.
What I have done...
- Replaced the fuel filter
- Replaced a few fuel lines that needed help
- Ran injector cleaner through it several times
- Replaced the DME temp sender
- Replaced the O2 sensor
- Replaced the AFM
- Replaced most the vacuum hoses in the system
- Did a compression test (was within spec, and consistent on all cylinders)
- Double checked my timing, which was right on.
- Replaced my wires
- Replaced my spark plugs
- Replaced the cap and rotor
- Cussed at it
- Replaced cables and grounds
- More cussing
It sometimes "seems" better but I think it's my butt dyno lying to me. It's become far worse and is a real pain in my butt at this point.
Culprits I have considered...
- Throttle position sensor. Although I tested it, and it seemed fine.
- Clutch, seems unlikely, but the worse the hesitation has become, it seems like the clutch chatters more. Although it seems to me a bit strange that it would/could be the clutch since it engages and disengages fine... unsure.
- Lifters - i do have some noise, it /mostly/ goes away once the car is warm.
- Gremlins - although I did not feed any after midnight, there is the possibility.
This is currently where I am at:
- Feels like when I step on it, it produces what feels like the "same" amount of power. Doesn't feel like it improves. Even if I give it everything. feels worse in 3rd and on... 1st and second it's there but not as bad.
- Sometimes it feels like the power comes on in spurts. It'll be there, then not, then it's there again, then sorta flat.
- Sometimes seems ok and "wakes up" but it's usually later rpms, 3k and on usually.
- Does seem worse when cold. Better when warm.
What I have done...
- Replaced the fuel filter
- Replaced a few fuel lines that needed help
- Ran injector cleaner through it several times
- Replaced the DME temp sender
- Replaced the O2 sensor
- Replaced the AFM
- Replaced most the vacuum hoses in the system
- Did a compression test (was within spec, and consistent on all cylinders)
- Double checked my timing, which was right on.
- Replaced my wires
- Replaced my spark plugs
- Replaced the cap and rotor
- Cussed at it
- Replaced cables and grounds
- More cussing
It sometimes "seems" better but I think it's my butt dyno lying to me. It's become far worse and is a real pain in my butt at this point.
Culprits I have considered...
- Throttle position sensor. Although I tested it, and it seemed fine.
- Clutch, seems unlikely, but the worse the hesitation has become, it seems like the clutch chatters more. Although it seems to me a bit strange that it would/could be the clutch since it engages and disengages fine... unsure.
- Lifters - i do have some noise, it /mostly/ goes away once the car is warm.
- Gremlins - although I did not feed any after midnight, there is the possibility.
This is currently where I am at:
Last edited by CorsePerVita; 09-13-2010 at 02:19 PM.
09-13-2010, 02:49 PM
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Derek, just 1 question: have you checked the output of the ignition coil? If the coil is erratic, the power would/could come on in spurts. Just throwin it out there...
09-13-2010, 02:53 PM
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Interesting point. I HAVE NOT checked this. I will test this when I get home tonight. Am still open to ideas though. Tonight is MAINTENANCE NIGHT! So throw'em at me! haha!
09-13-2010, 06:22 PM
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Got a suggestion from another friend today it may be my TPS sensor - I need to retest it and make sure it tests out okay again. Symptoms sound exactly what he described on a bad TPS.
Will test coil and TPS tonight and figure it out.
Will test coil and TPS tonight and figure it out.
09-14-2010, 02:00 PM
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The starting is fine and it runs perfectly smooth. It just has a strange hesitation like the power isn't "all there" at times. kind of like if you stepped on it, and all it wanted to make was 100hp and no more constantly.