2004 CTT Hesitation

[FormulaMatt]

Hello all - I am hoping you can help me. My CTT has around 90K miles on it. So far I have replaced the cardan shaft bearing, coolant pipes (including the t), and the faulty trans valve body. It has been doing great until the last couple weeks. It has developed a serious hesitation when accelerating past 30ish or so. It seems to only be when the CTT is warm. After the hesitation starts and the CTT is warm, it also starts to idle rough at that point as well. 

I have no CEL on and no codes stored in the computer. I have parked it and am driving my backup X5, but life in it is miserable compared to the CTT (although double the MPG has been nice!!  ). Can you help me figure out what to replace? I am thinking it is time for spark plugs and coils as those are originals and that is what it feels like, but thought I should have a CEL for that to be the case. I usually get my stuff from ECS as there are no local Porsche dealers around me for several hours.

Thanks for any help in advance!!

[lewisweller]

Hi and welcome to the ctt club for poor running and hesitation stutter. I have just completed one fix for my issues which are similar but not the same as your problem.

I think your correct and if 90k on same plugs and Coils definitely do them both regardless of cel codes. Then check back here with the results. Some cracks in the Coils and worn out spark plug electrodes is a good sign of the cause of the issue.

My issues have all revolved around lean misfires from vacuum leaks and Divertor valve diaphragm split. I just fixed the last piece of the puzzle the Divertor valve and drive smooth as silk for two days and just yesterday it back to stuttering and stammering hesitation like before, omg I nearly torched the thing. So there must be a vacuum hose or pipe somewhere leaking again! Idle is perfect, wot pass 4k rpm is very smooth and powerful but part Throttle at around 2k 3k is jelly and a lean misfire for sure.

Knowing it can run well keeps me motivated to keep at it regardless of the set back.

Good luck. And please post back, some people fix and never update and close their post.

[clarksongli]

Really just guesses at this point without any scans.....have you pulled any of the coil packs and plugs?

 

Drive the car like normal for a while, then come home and pulls plugs and coils.....you can tell a lot about the engine based on the plug color and condition.  Inspect the packs and see if you have cracks in them.

 

I don't recommend just arbitrarily replacing coils like Lewiswelller.....you could spend 400 bucks and still not know what the problem is, but as I mentioned, there is an easy was to diagnosis a whole host of issues with just the plugs.

[lewisweller]

If he's got 90k on original plugs and Coils wouldn't it be prudent even if he didn't have a engine issue to replace these? With Coils the latest revision is 21 that started at 00 says something about the reliability factor. Plus $ 400 don't get you very far at the stealer or indy these days, so if your handy with a wrench and it preventative maintenance too win win as far as I'm concerned. 

Only my two pennies worth, Good luck.