Porsche Enthusiasts Club Forum

Hello everybody...I have just joined the forum, primarily due to me having bought a 1989 944 S2.....





I bought the car at the beginning of the year, and spent £1000 on having all of the belts and engine seals replaced, plus a few other bit and pieces... the car ran very well after this....but has largely sat on the driveway....

I have occasionally taken it for very short runs locally, but a very uncooperative gear shift spoils the fun....anyway, I started it about 10 days ago and took it for a short drive, and it pulled very well.....I then started it a few days ago, and again it ran well, so I took it on a short blast...everything seemed fine.

When I got it home, I let it idle...it ran for almost 10 mins, then cut out.....when I restarted it, it wouldn't idle, and kept fluctuating between 600 rpm and 2000rpm...

When I attempted to start it the next day, it fired up, but then would not respond to the throttle...a slight noise from the bottom end, but not horrendous..now it wont fire up...

There is no coolant loss, and just very minor mayo in the oil filler.....no mayo in the dipstick....

I am not that mechanically proficient, but my guess initially when it wouldn't idle was the head gasket had gone...my logic being that it was losing compression, as it would not idle properly...either that or a problem with a valve....

I just wondered what others might think?

cheers

Bal

Firstly - welcome we are a friendly lot and you are in the right place!

Secondly - don't jump to the armagedon worse case scenario quite yet!!! I am sure someone will come up with a check list of other far more easy to fix possible things wrong. I would think that something (vacuum lines?) have been disturbed or perhaps the DME relay has failed??

Both these are random guesses, but do some searching here and as I said someone is very likely to be more helpful than me.

Welcome

I'd also start with air leaks which will cause unstable idle or stop the car running if the leak is bad enough. I'd be suprised if a head gasket failure would stop the car starting with no other side effects such a excessive steam or mayo.

I dont know the S2 engine well enough to say where to start but many on here do.

thanks

Hi Bal

welcome to the forum

As Rob stated check the DME...most of us keep spare DME's in the car ..I wouldn't worry about a small amount of mayo on the oil filler cap especially at this time of year as it begins to get a little damp out there. I would check all electrical connections for any corrosion, throttle position switch, reference sensors behind the engine( well they are on my turbo) etc as this can cause symptoms similar to what you have. Not sure about this bottom end noise, are you sure it's from the bottom?...some times if left standing for a while you may get some tappet noise or indeed get a tappet that gets stuck with gunge. If this doesn't clear after some time running try doing an oil flush and change....you can buy flushes designed to clear the lacquer that builds up around the tappets.

In general do a check on all connections and pipework....good luck

Pete

Have a look at the air flow meter, it's in the alloy box thing just before the throttle body.. You could have a dodgy connector or it might need 're-tracking', but one of the symptoms you've described can be caused by a worn resistor track - mine certainly were and replacing (the track was too far gone to be re-indexed) the AFM cured my problem...

Sounds like it's run out of petrol.

Hi everybody ......many thanks for all of your responses....Just to mention, I did actually just fill the car with a 1/4 tank of fuel just 30 mins before the issue began...I am going to start on the weekend by going through all of the items mentioned in your responses..I will keep you posted!

Wasn't diesel was it?

Lol!...no...not diesel

But...I just turned the engine over, and it fired, but didnt want to idle.....so i held the throttle open fully, and the revs would stabilise at 1000 rpm and then occasionally move up from there..........but would drop as soon as I let of the throttle

I have looked at the fuse box....I seem to have a non Porsche original DME.....with some burn marks on the board below where it sits...so, I think the first point of call is to buy a genuine DME...





In the meantime, I am going to check the plugs and leads, and start taking off parts of the air intake system to check and clean...

Ah, my old car.

I see the previous owner sold it in the end? I owned the car between 2009 and 2010. The history should tell you alot about the car if you have it but feel free to contact me for more info. In my time I never had the change the DME and it was a daily.

FWIW both of my 944s used to mayo up slightly at the filler cap and my last one had a head refurbishment months before I bought it. I put it down to the breather system of the car and shortish journeys. On long journeys I cannot remember the cap mayoing up. Not many cars have the crankcase vent tube also acting as a filler on the engine.

Is this the right DME: Porsche part number 993 615 227 01, £29 inc post from Frazer Part Porsche on ebay?

Hi... ....yes, there is a fair amount of history with the car...replacement engine/new clutch around 2009 I think...I think the previous owner ( a trader?) did not use it much and it sat around....and to be fair, I have had it a year now and barely used it!...so i guess some teething troubles are to be expected...hopefully, I will learn about Porsches!..

I fitted that type of DME relay into my 951 and it worked fine when the old DME began to play up (it would not start). Have you tried the 'DME jumper' trick to rule out the DME relay despite the small cost of a new one?

I fitted the new engine to that car and near enough a new cooling system. I can edit this comment out if you wish but that car is now on engine no.3. With one owner it went through 2 engines with the cooling system being seen as the main culprit in addition to a low oil level.

DME Jumper? Is that when you bridge the terminals on the relay with a piece of wire?....I could try that, but as you say, a new DME is peanuts.....I did have have the rad switch replaced when I had the belts and engine seals done....the oil pressure is perfectly acceptable now...about 3.5 bar idle?...but, I will have the entire cooling system checked/flushed/replaced as necessary....it will give me something to do on a weekend ....

3 wire jump will test DME theory.