EuroSport

Hi everyone. As some of you already know I bought a 1987 911 Coupe recently. A nicely maintained car with only 65k miles. I drove it for a month and didn't have any major problems. Now it is the end of the second month, and I just got it back from the shop. It was gone for the entire month. The problem is that the car dies at random. It makes no difference what speed, or temp, etc. It will drive along wonderfully, then suddenly loose power and the only way to keep the engine running is to push in the clutch. When you depress the clutch the engine almost dies (goes below 100 r.p.m.) then springs back to life. The mechanic tried the DME relay, replaced the throttle switch, checked the wiring connections, and lastly had the Motronic control box checked and rebuilt. He gave it back to me and told me to check it out. I didn't even make the 5 minute drive home without the sputtering loss of power.

Do any of you have this problem? Have any of you seen a way to fix this problem? After almost $1500 in trying to repair the car we are still no further. Any ideas, especialy if it is something I can check, would be greatly apreciated!! Thanks for all your help!!

H.B.

Eurosport,

I had the exact same problem. After replacing several sensors, they ultimately replaced the DME control unit itself and this solved the problem. Have you tried replacing/updating the cylinder head temp sensor? It's known to cause problems similar to the one your described.

George 86T

Euro--I agree with H.B. that your symptoms could be caused by the head temp sensor (#3head)--especially if it is a ONE wire model. The newer sensors have two wires--the second one providing a ground connection rather than depending on the sensor/head machanical connection. The sensor screws into
a dissimilar metal and corrosion develops ruining the ground in the one wire model. You can check that ground connection by clipping an alligator clipped lead to the barrel of the sensor with the other end clipped on a good ground elsewhere on the engine. Then test drive it. If it still fails--it's not the ground connection. If that clears up the problem--you've got a $75 part to buy!

EuroSport

Ok guys I just went out for a test run to be able to better describe the symtoms. It seems there is only a little problem when the car is cold, but as it heats up it only get worse. So I drove the 10 minutes to where I work, and it started getting nasty as I got there. When I turned around to go home, it completely died and wouldn't let me start it back up for a few minutes. Once restarted it wouldn't let me move, dieing as I let the clutch out with the transmission in 1st. So I called a tow truck and while waiting an hour, the engine temp dropped. I was then able to start it and make the 3 last blocks home.

So I am guessing you guys are probably right that the "symtoms could be caused by the head temp sensor (#3head)". My reasoning is that if it is the temp sensor then the hotter the engine got, the harder it would be to get a good conection. So that is why I was able to get 'er going after a 45 minute rest. Does this make sense with this kind of problem? What exactly is the job of this semsor (getting the temp obviously)? Why would it cause my car to loose power and rev the engine at random??

Thanks guys!! I think we are getting closer.

richard glickel

ESport,

Had a dying problem at about 50,000 miles. It was the brain (DME), which had to be replaced. Even though the car was off warranty at the time, Porsche agreed to pay for 1/2 the cost of replacement.

But, if I read your post correctly, you have already tried replacing the DME, so the temp sensor could be your answer as George suggests.

Good luck.

Richard
'87 Carrera

EuroSport

Well everyone. It is a sad day. I went to pick up the car from the shop. I had them put the ground on the temp sensor on the #3head. I drove the car to grab a bite for lunch and it didn't even make it out of the parking lot at the restaurant. I had to have the car towed. So I still have no clue as to what is causing this problem. Do any of you have any more things to try?? Should I try the other temp sensors (are there others)? As always any help would be greatly appreciated!!

richard glickel.

Esport,

I think you need a new DME. The way we figured this out on my car(after about a month),was we swapped my expired brain for a new unit. That did the trick and Porsche was really terrific about sharing the cost of the repair (part was $500) even though the car was off warranty (over 5 years & 50,000 miles). Of course, they could tell that the car had never been abused and was very well maintained.

Smart move on their part as they now have my owner loyalty forever!

Good luck.

Richard
'87 Carrera

richard glickel.

Esport,

I tried sending you a reply email but received an error message (you wouldn't believe the day I'm having with this computer). So here's my reply:

It was around 1995 or '96. The car was about 8-years old at the time and had between 50-55K miles. I am the original owner. I called Porsche (they were in Nevada at the time), at first "they" (the one nasty person I spoke with) were sort of unpleasant. So, I wrote to Porsche N.A.

My pitch to Porsche N.A., basically, was that in my own humble opinion, the DME should not go on a car that cost approx $50,000 (mine was bout $46k new), and certainly not on a car that bore the family name of Dr. PORSCHE ("there is no substitute", right?). Their regional rep (a nice gentleman named Helmut, since retired), called me and stated that I had to take the car to a Porsche dealership (at that time the one near me had gone out, so I took the car down to Jack Daniels in New Jersey), where he could see the car and, if they confirmed it was in fact the DME, Porsche would split the bill with me, which they did.

That said, I don't know how they'll react to a 15-year old car at this point. But, you've nothing to lose.

Let us know how you make out.

Richard
'87 Carrera