I am at my wits end on this one -
From a cold start and minor warm up to get oil circulating, it runs perfect. The more I drive it and the warmer it becomes (not hot)
it begins to run like crap. It will pop back, run only on 7 cyl.
This is what I have done:
1) new plugs
2) new wire set
3) clean injectors
4) cleaned the 14 plug connector
5) cleaned the connection to the coil
6) can of Techron

I just ordered a new green wire from Roger.

Could it be fuel pressure?

 

how to the vacuum lines look? do the ones off the dampeners and regulate smell like gas?

 

I have checked the vacuum lines numerous times, no gas smell
I did have the intake off recently when I had all the injectors cleaned. The heater is intermittent. ( some times it works sometimes it doesn't )

 

Install the green wire

 

Thanks Merlin, I was hoping you would endorse this.
If nothing else I can cross it off my list

 

+1 to Stan,

 

Intermittent heater - air bubble in the coolant ? Assuming its K-jet ----I had a misfire in mine once, and I was able to isolate it to a specific cylinder. The problem went away after I cracked open the injector line to that cylinder. My local wrench who does a lot of work on K-jet 911s guessed that it might be a piece of crud in the distributor head blocking that injector outlet. After about the third such event, it never came back.
jp 83 Euro S AT 55k

 

Since its an L jet......(if the green wire doesn't fix it) try this...take resistance readings of the temp II....if that is in normal range than pull the L jet plug in passenger footwell and take resistance readings for the temp I sender which is inside the AFM..... If it is even slightly off, it can do this....my lemons racer had this problem....a new (used) AFM fixed it right up

 

I just put in a new green wire and this seemed to help a bit but didn't correct the problem. I think Brian is on to something but getting the readings of the temp II is a bit over my head. Is there a thread that can walk me through it?

 

https://rennlist.com/forums/928-foru...ii-sensor.html

 

Looking through the PET catalog I cannot find the TEMP II part. I don't even know what it looks like. Is it the Lambda sensor?

 

bump

 

from of the water bridge by the heater hose connection.

 

This is what I suspected but wasn't sure
Thanks

 

Don't overlook a MAF out of calibration.
My S4 what you have described. After 3/4 hour of highway driving a loss of power and lean popping.
Swapped in a good MAF and problem gone.