kosh

My 964 started playing up this morning.
The engine keeps dying - its as if the choke isn't cutting in??

I managed to get the car to work but had to use the handbrake to stop the car and keep my foot on the gas.

Another thing I noticed is that it missed a couple of times on a couple of straight spurts. (only time tho)

Somehow I've just got it to tick over and can hear quite a loud 'clicking' noise from the top of the engine bay (is this where the choke is incidentally??).

These are the things I have done to the car over the weekend they may help you to help me......

I jet washed the car on friday BUT I have put the car on and off the drive TWICE since then.

Last night I realised that the passenger front beam bulb was not working so I took the lamp off replaced the Hallogen and after putting it pack together realised that it still didnt work so I went in to the fuse box to see if the bulb had took a fuse with it. couldn't find the correct fuse position so I checked all the 7.5amp's. - they were all fine (another mystery).
Could I have knocked something there? - The car was running ok before then, but not after?

I do think this is electrical and I have seen something similar with my wifes clio and it was one of her HT leads shorting on the block.

In december I had a full engine out service with new leads and dizzys so I don't think it's exactly the same problem (maybe see more once it gets dark).

PLEASE help i've got to get home!!

Thanks

Its a UK 1990 964 C4 targa

IanR

If you were checking fuses, might have knocked a relay. Make sure all the relays are seated properly - they're in the fuse box.

John Boggiano

Also, if it does turn out to be elctrical, disconnecting the battery, waiting a few minutes and then reconnecting might help.

bpras@msn.com

Do a search on testing the coils. When you remove one of the coil wires it mighr run well enough to get home. Good luck!

kosh

This is weird...

It's fixed itself.

Can't get it to replicate the fault - thrashed it about - left it a couple of hours, went back to it and it just wont do it again.

PCT said it sounded like the belt on the dizzys had gone but now its ok so now im really confused?!!!

Any thoughts?

DAVISRILEY

Kosh, try this http://www.troublecodes.net/Porsche/ and see if you have any codes. May help. Good luck.

jimq

sounds like water dried out that had gotten in a corroded electrical connection.

jhummel68

Sounds like the same thing on my dad's 964 a few years back. It would run rough for a while and at times die then a spirited departure from a stop light or just getting it into the higher rev area would smooth things out. This lasted for several month's and we could not figure it out. We finally put a timing light on both sets of wires and found one distributor not turning (stuck on cylinder 5 if I remember correctly). If you have access to a timing light or if you disconnect the hot lead from the right or top distributor it may answer your question. GL

Rennen

I'm guessing that the water in the engine bay was causing some arcing from the distributors or plug wires. This sounds very much like my situation a couple of years back when I got my engine bay very wet with new plug wires that had split and the arcing basically shut the car down. I had to replace the plug wires again when I discovered that I had ultimately caused the problem by nicking a plug wire when I did the first replacement.

kosh

PCT mentioned pulling a HT off...
Can you just check the procedure.....
Assuming I can get it run rough again
1) Remove center HT connection from top of dizzy cap NEAREST to fan housing.
2) Attempt to start car
3) If Car runs the same then dizzy not working at all (belt snap)
4) If Car runs rough then dizzy is Ok but a lead has a fault - Then try each lead until I find one that when I remove makes no difference (thats the line the fault resides)
5) Wont start at all - Fault is in the other Dizzy.

Is this correct?

I'm sure on my last £1680.00 service I had new Dizzys & leads - Ill check the paperwork when (if) I get home tonight.
Thanks

kosh

davisriley, thanks for the link but I'm not that competent. Useful thing to have when I next visit my specialist.
Thanks

John Boggiano

How's your DME relay?

kosh

John,
Never replaced it in the 6 years I've owned the car.
How can I tell if its faulty?

Can someone please confirm the procedure above for checking the dizzy's


Thanks

Benengo

I had the same symptoms with mine. turns out it was the dizzies but not the belt as per sooooo many others. turns out that the belt was slipping and as such was fine most of the time but intermittently i had exactly the same issues.

If you do manage to reproduce the fault, get the cover off and make sure everything is running smoothly.

failing all that, someone told me that the air idle valve, if sticking, could produce a similar effect?

John Boggiano

As I understand it (and we might be going off the point here), one of the common signs of DME failure is that the engine will 'run' while you're operating the starter but die once it's on its own.

I had a few fail, and sometimes the engine would run at idle, but didn't want to know as soon as any throttle was applied. It basically manifests itself as reduced current to the fuel pump, so it can give rather vague symptoms sometimes. After six years, it's got to be worth changing anyway I would have thought.