Engine failure while driving

[bboris]

My 1987 3.2 Carrera just had to be towed. It drove perfectly this whole weekend including city and highway driving. Today, I decided to take the highway and just after entering the highway things went badly. The car started to “stutter” when I accelerated. I changed from 4th to 5th gear, but the same “stutter” occurred. The oil warning light and the battery light lit up (maybe other ones as well but I might have missed them as I was somehow stressed). Therefore, I drove to the side of the highway and turned off the car. When I tried to turn it on again, it would not start.
Hopefully, nothing major. I had them tow it to a local air cooled specialist. Hopefully, nothing major. I will know more the next couple od days but does anybody have an idea what happened?

Thanks,

Boris

[AG81]

Sounds like a bad DME relay.

[tmadden2]

Same thing happened to me. Had to get flatbedded back home. It was the DME. I don't leave home without a spare anymore.

[Rodsrsr]

Sounds like a classic DME relay failure. If it turns out to be the case pick up the redesigned Solid State type and you wont have to deal with this again. Otherwise as others have said, keep a spare.

[sugarwood]

Can anyone confirm that when the DME relay goes bad, the oil and battery lights come on ?

[Rodsrsr]

Originally Posted by sugarwood

Can anyone confirm that when the DME relay goes bad, the oil and battery lights come on ?

Its not that a failed relay triggers the lights, rather the engine stalls and since the key is still in run position, the lights come on.

[bboris]

Dear all,

Thanks a lot. That is reassuring. I just purchased the car in April so that I am quite new to the vintage car experience. Actually, I had a spare DME relay with me after a friend had recommended to always have an extra one in the car. Unfortunately, I was not aware that this was the issue. But also, I guess it would not have been safe as the highway was quite busy at the time (the pic does not reflect that).

Thanks,
Boris

[famoroso]

Originally Posted by Rodsrsr

Sounds like a classic DME relay failure. If it turns out to be the case pick up the redesigned Solid State type and you wont have to deal with this again. Otherwise as others have said, keep a spare.

Solid state relay FTW! Don't leave home without it. I have one in both of my cars. I prefer the pump prime unit... 911 Solid-State Relay — Focus 9 Technology, LLC

[Jesse16]

When my relay failed 3 years ago the car simply quit running and I coasted into a side road. After a short period of reflection, I remembered the tattered box in the glove compartment and gave it a try, no tools required. Fired immediately and got back to the in-laws where I fastened it down correctly and ordered another for the same tattered box. I had no sputter or prolonged failure but no idea what the different ways it can fail are.

[86 911 Targa]

Yup!

Keep a spare in the glove box!

Gerry

[GH85Carrera]

When my original, installed by the factory DME relay failed is was intermittent. Just driving along it would stutter for a second, and then clear up. I swapped it, and all was fine for many years.

I have the sold state one in the car now, but I still carry a spare DME relay and once I was the magic man when a friend at a Porsche event has his DME relay fail. I just happened to have the spare he needed.

Sometime they just die and the car will not run at all. Sometimes they just partially fail, and the weird symptoms start.

[Arne2]

The DME relay has 2 functions — it powers the fuel pump and also the ignition. If the ignition side fails, the car just dies. If the fuel pump side fails, the car sputters as it runs out of fuel.

[JohnTucker]

I freaking love the previous owner of my car. Reading this thread and I'm thinking...this sounds familiar. Double checked...and sure enough...spare DME Relay in the glovebox. Awesome.

[sugarwood]

Also keep a 10mm wrench, otherwise, your spare DME will stay in the glovebox!

[JohnTucker]

LOL...I will check. The full OEM toolkit is in the frunk...but I don't know if there is a 10mm wrench included. Thanks!

[HaroldMHedge]

Yes, the Carrera has a 10 x 11 mm double open ended wrench, 999-195-012-02, in the tool kit. Though it may have gone MIA over the years.

[JohnTucker]

I'm good! I just pulled the toolkit out (it's still has the original plastic bag it was shipped in) and checked. It's got the 10mm + what looks like everything else. Even the belt. LOL. Again...amazing previous owners.

[Quicksilver]

A spare DME relay is nice but as an "emergency piece" I keep a DME jumper in the car. Because it is simply 3 connectors hooked together with wire you can visually see that it is correct and with any DME relay you would always have a question what is happening inside the box.


You just crimp some wire between three .157" male bullet connectors. Dirt cheap and pretty impossible to fail. The 3 sockets you need to connect are #30, #87, and #87b. (I have the numbers on labels on the leads so I don't have to remember.)

MAKE SURE YOU PULL THE JUMPER WHEN YOU TURN THE CAR OFF!

[bboris]

Dear all,

Thanks so much for all your input. This community is truly outstanding. Just to give you all a brief update, the problem was indeed the DME relay.

Thanks again,

Boris