964 Turbo bad hot start and running problems help please!!

gulf blue rsr · 10-25-2009, 09:09 AM

Hi I've got a 92 964 turbo.

I've posted the same thread in the turbo section so hopefully it's ok to post this here as well?

It sat for 12 months whilst I waited to find time to put a clutch in it.

I put the clutch in and all back together started and ran great, good to driving it again!

I used it for a few short runs locally a few times just to make sure everything was well after it standing and then putting the new clutch in, all seemed fine.

I took it for a longer run (only 80 miles) one evening and all was good, parked and left it for 1 hour or so, went out in it to go get some food and it was running bad, coughing and backfiring all the time, if I held my foot down it would clear and eventually rev through but not happy.

I left it stand for a couple of hours then drove the 80 miles home again with no issues???

car stood for a few days, started great from cold, popped into town left it whilst in the shop for 10 mins and did not want to start again?

Struggled to get it home for 3 miles popping and banging lots of backfiring all the way.

It has been sat for 3 weeks until I had a chance to take a look today, I've checked for leaks around the intercooler, even sprayed carb cleaner, I'm pretty confidant there are no leaks, when I start it and drive from cold it runs and drives fine, as soon as it warms up it all goes wrong!!! leave it stand for an hour or so and starts and runs ok again.

Any ideas anyone?? I've tried searching and not come up with anything really that sounds like this problem!

Thanks

STEVE

WPOZZZ · 10-25-2009, 04:20 PM

Maybe some kind of vapor lock?

Black_Hat · 10-25-2009, 04:30 PM

check fuel accumulator

80-911SC · 80-911SC's Garage

isnt a 964 turbo a 965 ??

WPOZZZ · 10-26-2009, 12:25 AM

Quote:

Originally Posted by 80-911SC

isnt a 964 turbo a 965 ??

Nope.

gulf blue rsr · 10-26-2009, 02:44 AM

Thanks for the suggestions, just wondering if there is a problem with the accumulator would the problem not be there all the time not just when hot?

Is the accumulator serviceable? any suggestions on how to test it or clean/fix it?

Yes the 964 Turbo is referred to as a 965 just that some people get upset by it being called a 965 as this was actually a abandoned project by Porsche so I thought it would just be easier to just call it a 964 Turbo so everyone knew what I was talking about.

Thanks again and keep the help coming!

Steve

gulf blue rsr · 11-01-2009, 04:25 AM

Quick update.....

I now think that it is ignition related as when it would not start whilst hot I checked for spark and there was none, after cooling it came back and ran again.

Now suspecting possibly coil, crank sensor on the flywheel or the ez69.

I've been doing lots of reading on the ez69 as I'm also wondering if this may be at fault, I found a thread from a couple of years ago that had a problem with his ez69 near the end of the thread someone came in with a fault that sounded exactly the same symptoms as mine, good when cold bad when hot, his problem was solved by cleaning and adjusting the flywheel sensor, I have taken out the sensor and cleaned it, it was a bit oily on the end but also it looked like the inside was denting the end out a little not completely flat if that makes sense? should it be flat or could it be faulty if it was starting to dent out? almost as if it has had a good shaking and something inside had tried to get out!not a lot just not flat.

I put it back together and ran it a tickover till it got hot and back came the problem!

Does a failing ez69 give the same sort of signs? does a failing sensor give these signs?

Need to get this sorted, car stood for 12 months while I tried to find time to sort the clutch I get to drive 1 tank of fuel and now its sat again!!!

Thanks for the help keep it coming please!

Steve