Greydog

Hello all!

I've been looking for an answer to this for weeks.
Actually, a more accurate description of the problem is as follows:
1) Car starts and runs beautifully cold/cool with plenty of power
2) After about 45 minutes of pretty hard driving, at about 5k RPM it's as if someone cut the gas and ignition for a few seconds then it runs for a few minutes it will do it again.
Eventually I can't reach 2.5k rpm and getting home is almost impossible.

So far I've changed plugs, fuel filters, ran some Sea Foam fuel treatment through it.

I'm inclined to blame the ignition igniters being as it only does it when the engine is hot and get progressively worse the hotter it gets.

Any ideas? Sorry for the long post

diabolical1

iTrader: (3)

did it ever overheat?

start with checking the compression.

satch

iTrader: (1)

Have you ruled out the exhaust system?

Greydog

Hi Guys.
The car has never overheated. When it is at temp., it runs smoothly and pulls great.
The exhaust is new cat back. I haven't checked the cat.
Is there an easy way to check it? Short of installing a "test" pipe?
Thanks fro your replies.

FührerTüner

iTrader: (5)

I would check grounds. Sounds like something to do with when your secondaries kick in.

Greydog

Good idea about the grounds.
I just got back from a test ride and the same problem occurred.
I checked for exhaust smoke = none.
I pulled over and on a whim, turned the key to off and started it back up ....it ran perfectly.
I'm going to drive it again when it cools off to see if it duplicates.
Thanks for everyone's help.

satch

iTrader: (1)

You might want to test the Water Thermosensor, and both air intake sensors with one being in the AFM and the other on the engine.

Greydog

Thanks satch...I'll try that.
After my second test drive the problem came up again. I shut it down restarted and again, it rana fine.
Strange, no?
.