87 3.2 shut down travelling on the highway

[BReyes]

87 3.2 shut down travelling on the highway.

I need corroboration. I'll let you guys know more as i know more tomorrow.

Driving her at approximately 4000 rpm in the morning and again in the afternoon. So that a couple of hours spirited on the turnpike and interstate. She was running very smooth, as usual, this morning.

Background: Recent service by well qualified tech to diagnose/correct irratic oil pressure guage. Little over an hour to fix faulty wire to the sending unit down by the right side f the fan housing. All else checked out. Also had the fluids changed in the motor and transaxle.

So anyways, I'm on the highway on route to the airport, and feel a little miss, similar to a loose spark plug wire, maybe. Ok. I'm not stopping, I'll just slow down a bit until I can exit interstate and take a look under the deck lid. Well maybe ten minutes later, she shuts down, so i drop it down into second and get her going again, but there is a miss. I exit immediately, and pull over.

Car won't start. Ok no problem i think, let me see if there is a loose conncetion somewhere. I touched all the wires i could, as well as the fuses and relays under the hood, also checked all ignition wires to spark plugs and distributor to coil. It just spins, and spins when I try to start it. No fuel or spark. Over a half of a tank of premium. Too much noise to hear fuel pump.

I call road side assistance, and they call me back with a towing company on the line, but my cellular dies aparantly from sweat from my face getting into/under the battery. I know. I know. Its a Monday. What a doosy.

So I flag down a cab. I go to a local shop "International Auto Works" in West Palm Beach FL, since cabby shows me a card, ASE certified and a pic of a 911 on the card. The owner says he knows Porsche. I had to get to the airport, for an a.m. appointment.

In the morning I will call the shop.

What would you say is wrong with the car?

I appreciate your input.

Thank you.

Regards.

[jester911]

Check plug to the air flow meter. Car will not start without it.
Also check the dme relay under the seat. All I can think of right now.

[madmmac]

2x on the DME relay under the seat.

CHT (cylinder head temperature) sensor and the speed sensor on the flywheel could also be suspects.

[imcarthur]

Could also be fuel pump. Mine died as I was accelerating onto an onramp . . . like a switch turned off.

Ian

[BReyes]

It was a warm day. I didnt think to look in the glove box for a dme I put in there acouple of years ago when throwing parts at it from what was infact a fuel pump. But I am not sure if I pulled it out and put it in the tool box either.

I touched the wires to the AFM and connecttions seemed ok.

I touched the three connections behind the cruise control and all seemed alright.

I didnt think of the speed sensor or the CHT sensor. CHT is a year old from a top end rebuild. And the speed sensor did act up when I put the motor back i nlast year giving me a little hesitation- which I was going to get in there and check the gap- but it cleared up without any regapping.

The car was running real well until this.

I am corroborating with members on the board so I will be a step ahead of what I hear from this shop (as I never seen their work before).

I appreciate any more input, and will let you know what more I learn.

[stealthn]

Battery...Alternator

[Hugh R]

On my 3.2 it just quit one day. Turns out it was an internally shorted fuel injector, gave no, or a shorted signal to the DME I don't remember. Took TRE three days and $$ to figure it out. Said they'd never seen that happen before. Another one to check.

[charleskieffner]

Originally posted by Hugh R
On my 3.2 it just quit one day. Turns out it was an internally shorted fuel injector, gave no, or a shorted signal to the DME I don't remember. Took TRE three days and $$ to figure it out. Said they'd never seen that happen before. Another one to check.

wow this one got my attention!!!!!! my final diagnosis after everything mentioned here already was filthy POS old MAS! same problem you have mentioned, ran great then just died.................WTF!!!!!!

[scottb]

Originally posted by stealthn
Battery...Alternator

When my alternator died, the symptoms were simlar to what Bernard is describing. So, my vote is also for a bad alternator.

[ZOA NOM]

DME relay under the seat. Start there. Many many stories of stranded 3.2's because of this relay. Buy two, and keep a spare in the glove box.

[Blanco]

Oh snap. Mine did this the other day. It backfired then caught as I was trying to make an emergency stop. I exited at the next exit and check under the car and wiggle the wire going to the coil. I started it and still hasn't happened again.

[SteveM911]

DME relay under the seat is most common point of failure with
this sort of shutting down of the engine.

[JTL]

My car died without warning on the wife's birthday, no less. It restarted after a while but the rpms went wild and then it died for good.
I try to be prepared by having a spare dme relay in the boot swapping the relays didn't help. Problem was no spark caused by a bad flywheel sensor.

jt
-84 targa

[BReyes]

Update and a question:
I finally was able to speak with shop, after several calls to the number on the business card with no answer.

Very nice people and seem to be well intentioned. I had originally told him to find out what is wrong with the car before doing doing the work.

Yesterday, I asked for them to check if i had the DME in the glove box. And if he knows what a DME is. He replys, "no, what is a DME". I explain. Hmmm hmmm.

This morning hear no DME inside the glove box. Advised there is no fuel. It is probably the fuel pump. But not sure. One of his friends around the corner works on older Porsches, that he (his and his family's shop) has worked on newer ones.

I wanted to send someone to take the car out of there for me, but I am out of town.

I asked if he would put in a new DME in for me and let me know if it starts. Replys, he didnt want to throw parts at it, but would if that is what i wanted him to do. I said yes. Then I call Braman Porsche to check on availability. Parts tells me they do not have one in stock, but can check for me who has one in stock. Tells me Champion Porsche has one, rebuilt. I have never heard of that, I told him. He said yes they may be rebuilt, and there is another small shop in WPB that rebuilds the DME too. By the way, I find out Braman can order a reference and speed sensor if needed. I called the shop back since I told him to install a new one. Well his source doesnt have one but is checking who does. I told him Champion has one. Reply, who is Champion. I explain.

I'll be back in Florida tomorrow.

With a new DME, if it doesnt start, how do I check the fuel pump? The unit in the car is a Bosch unit installed by Zots a couple years ago.

Regards,

[MotoSook]

I don't think you want a new DME ($$$ or even a rebuilt one), but try the relay first. It's a cheaper part. I always carry a relay in my tool bag.

You can have the shop test the reference censors for resistance. No need to replace them if they are not bad. Better you buy a good multimeter and carry it with you. When the car shuts down check those resistance in case a wire is shorting when hot.

You can bypass the DME relay and run the pump. You can run it with a fuel gauge on the pressure test port. Or just run it to be sure it hasn't crapped out.

Get the Bentley manual if you are in an area with such a poor selection of aircooled wrenches.

[imcarthur]

As Souk said . . .

Make sure you are asking everybody for a DME Relay. The DME is the whole 'computer'.

The Bentlley has a simple fuel pump test: 240-6 that worked for me. Unplug DME relay. Jumper terminal 30 & 87b with a fused wired with a toggle switch. If you make the wire long enough you can lay under the car to hear/feel the fuel pump. In my case (dead fuel pump) it didn't run with this test.

Ian

[KTL]

To check the fuel pump you can disconnect the connection to the filter and see if any fuel is pumped when you try to start the car. It's best to catch the fuel that is pumped (if any) in a container! Yet I think Souk's suggestion of the test port is a better location. It's right in front of your face on the driver's side fuel rail, above the distributor.

Spare DME relay is good to have just for this purpose- you stick in the spare and see if fixes the problem, and that potentially isolates one failure point.

Alternator shouldn't kill a car altogther. Car can run without it- but not without the fan of course..... If the alt. died, the battery light on the oil temp, press. gauge should have warned you. If not, check the battery for voltage.

Definitely check the coil wire to the distributor. Simple check, but checking the coil is not without multimeter.

[glenncof]

Frantic decision making and throwing parts at the problem will likely make things harder to diagnose as ANY changes creates more variables.

Recently, after more than 150K miles/15 years without leaving me stranded, my 1985 911 would turn over but not start. I thought this may be a first ! I suspected fuel pump since I didn't hear it and wiggled the fuse for it. Finally started and got home.

I could run the fuel pump by connecting fuse 17 to fuse 18 (or whatever per Haynes manual), putting 12 V directly to pump. It ran fine. Put the voltmeter on the pump fuse, turn on ignition and had intermittent 12V feed on cranking (note; must be cranking, not just ignition on). Reverified this and check schematic. Concluded DME relay (no they don't rebuild relays) and ordered replacement.

Six months after replacement, never a problem. No, they don't always go this smooth. Until this happen I had never heard of a DME relay. Forums like this and rennlist are great places to seek diagnostic help but verify the theory of the failure before replacing anything. I have spent $1000s on Porsche mechanic and at times, not fix the problem. Now I do it myself and find verifing failure mode leads to correct repairs.

[BReyes]

I needed the car next weekend so I went Saturday morning and had car towed out of that shop. I found it with the air filter removed, and the throttle body loosed. Not happy about that but just tightened it all my self and let the tow truck take it.

Ryan Noble of RS Imports, in Jupiter, has the car. Ryan says the DME is bad. Hasn't found a used on from a reputable source. Yet I have been told Porsche in Atlanta doesnt have dme relay. He said will replace the dme relay with a new one. I told him about a shop in Boca-Programma-referred to me by parts man at the Dealer in West Palm Beach, that can rebuild it. He said I know them, and spoke with them about rebuilding it, and told me what they charge. Pelican doesnt have a DME.

Now I am wondering what will happen to the way car runs with new dme. Mine used to run strong, and rev into 7200 rpms if I let it ( I don't let it rev past 6500 normally).

Any thoughts?

Regards,

Ryan says the signal goes in but not out. That the fuel injectors are pulling 6 instead of 2 microseconds(?). That the reference sensor ohms out ok. Two day turn around from Programma to rebuild it. I called Ottos in CA but number rang busy.

[scottb]

Have your DME shipped to www.systemsc.com. A fellow Pelican, Loren, owns the company, and though he can be a bit acerbic at times, he knows his stuff. He'll diagnose and fix yours, or sell you a rebuilt unit with a warranty.

Scott