Intro and first problem.

[85Shark]

Ok, I know I'm going to get hosed on the fact that I have had this car for a year and not made a formal intro, but here it goes anyways.

The car was going to be a "cash for clunkers" but I was offered it first before his wife made him ditch the car. Man I'm glad I did, and after what he had heard about his taxes he was glad he sold it to me.

1986 3.2 Targa 98k on the odo. no rust, straight, interior is in need of repair but fine for now. The car had no records (bad I know). My 928 had every record from day one, oh well again the price was right! He was the 2nd owner and only had tune-ups done. Car actually sat for 4 years, prior to his ownership. He cleaned it up and tuned it and ran it for 50k before I got a hold of it.

Last fall I just enjoyed a great drive i was really surprised how well the car ran and handled. It was completely stock, and pulls extremely strong, but has the usual issues with 1st gear syncros and minor oil leaks. Over the winter I removed all of the AC equipment front to rear non operational. I'm also in the process of backdating the heat. New installed M&K Cat bypass, M&K one in one out exhaust. New plugs, gaskets,dizzy, new oil/filter, O2 sensor, Lina Corsa wheels. And I have been picking up spare parts where ever I can. Also have a SW chip mapped for 93 octane (yet to be installed).

Now to the problem. Since it has been in my possession I have put on about 2k with out one single hick up. Last Friday I left for work and pulled in to get some gas. Car started as usual first crank meet with the usual growl of a flat 6. Like I said pulled in and gassed up. Went to start and the engine just cranked and cranked. Now the gas station is a mile from my house so the car was no where near warmed up. This continued for about 5 min. The engine then turned over and I was pleasantly surprised to hear her run strong without a beat. Took it out for a spirited run on the freeway and a nice warm up, approx. 35 miles. Stopped for some coffee and she fired right up again. Off to work no issues pulled strong through all gears. 3 hours later off to a meeting and nothing, cranks and cranks and no start, waited a couple of hours and tried again. Now I have tried a few things that came to my head, new DME relay, checked for spark and that's fine. I just have a feeling that it has something to do with the fuel system. I have not checked the fuel pump yet, or the injectors.

Can someone give me a check list of what to check next?

I do have the Bentley Manual as well as our hosts book 101 projects.

Thanks for your time and I am looking forward to getting her back on the road, these are an absolute blast to drive.

So on with the pics:

[msublett]

Mine did the same thing, replaced the fuel accumulator and haven't had a problem since.

[86 911 Targa]

Originally Posted by 85Shark

Ok, I know I'm going to get hosed on the fact that I have had this car for a year and not made a formal intro, but here it goes anyways.

The car was going to be a "cash for clunkers" but I was offered it first before his wife made him ditch the car. Man I'm glad I did, and after what he had heard about his taxes he was glad he sold it to me.

1986 3.2 Targa 98k on the odo. no rust, straight, interior is in need of repair but fine for now. The car had no records (bad I know). My 928 had every record from day one, oh well again the price was right! He was the 2nd owner and only had tune-ups done. Car actually sat for 4 years, prior to his ownership. He cleaned it up and tuned it and ran it for 50k before I got a hold of it.

Last fall I just enjoyed a great drive i was really surprised how well the car ran and handled. It was completely stock, and pulls extremely strong, but has the usual issues with 1st gear syncros and minor oil leaks. Over the winter I removed all of the AC equipment front to rear non operational. I'm also in the process of backdating the heat. New installed M&K Cat bypass, M&K one in one out exhaust. New plugs, gaskets,dizzy, new oil/filter, O2 sensor, Lina Corsa wheels. And I have been picking up spare parts where ever I can. Also have a SW chip mapped for 93 octane (yet to be installed).

Now to the problem. Since it has been in my possession I have put on about 2k with out one single hick up. Last Friday I left for work and pulled in to get some gas. Car started as usual first crank meet with the usual growl of a flat 6. Like I said pulled in and gassed up. Went to start and the engine just cranked and cranked. Now the gas station is a mile from my house so the car was no where near warmed up. This continued for about 5 min. The engine then turned over and I was pleasantly surprised to hear her run strong without a beat. Took it out for a spirited run on the freeway and a nice warm up, approx. 35 miles. Stopped for some coffee and she fired right up again. Off to work no issues pulled strong through all gears. 3 hours later off to a meeting and nothing, cranks and cranks and no start, waited a couple of hours and tried again. Now I have tried a few things that came to my head, new DME relay, checked for spark and that's fine. I just have a feeling that it has something to do with the fuel system. I have not checked the fuel pump yet, or the injectors.

Can someone give me a check list of what to check next?

I do have the Bentley Manual as well as our hosts book 101 projects.

Thanks for your time and I am looking forward to getting her back on the road, these are an absolute blast to drive.

So on with the pics:

Nice Clunker...................

[steely]

Drew,

Nice story - beautiful car - thanks for the pics - no hosing here.

I could be wrong, but I don't think 86 have an accumulator.

Others will weigh in on potential temperature and other related issues.
Only experience I had (farther down the troubleshooting list) was an issue with the aging speed/ref sensors - but like I say, this may be reaching.

Checking for fuel and spark when it is working may be problematic.

[Steve@Rennsport]

My vote is the DME relay.

Don't forget, these (overworked) relays power the ECU as well as the fuel pump and if they become intermittent or suffer an outright failure, you are going nowhere without a spare.

Matter of fact,........carry two spares. Their QC as of late isn't very good.

[dshepp806]

Yes,..step ONE: DME relay.....

Then off to look at the fuel pump fuse and holder connection integrity.......maybe some fuel pressure checks would be good data points?

Back to step one................

Ready?

Doyle

[85Shark]

Thanks Steve, as I said I did replace with a "new DME" but I can not say that it was a functioning new relay.

[steely]

try a known good dme relay.
Intermittent failures are the worst - can you drive it around and come home to try to reproduce the prob - try a restart? - see (bad word choice) if you can hear the fuel pump.
Am leaning away from all injectors, but Doyle may have a point with the baseline pressure check.

fuel filter, pump, rotor, dizzy cap, coil - not necessarily in this order - or DME is saying 'no' for some reason.
There's a troubleshooting list in the Bentley I think.

[mike5876]

i say coil

[magnumpi]

Sweet ride Drew.

I'm no expert but it sounds fuel related...fuel pump going?

On another note...are you going with the stainless targa bar? I am in the same boat, thinking of taking off the flat black paint (it's stainless underneath), but I'm not sure it looks right with black trim. Looks much better with chrome trim, IMHO.

Good luck.

[AVIMAX]

I am no expert, but my '86 quit on me last summer. It died, then started and drove for 5 mins. twice, then died completely. It would turn over, but not start. For me it was the DME relay, and when I took the relay apart, I can see why. One of the solder joints one the circuit board is cracked all the way around the contact. Take a look at you old one, it is easy to open, maybe there is a cracked solder joint. The other thing you might want to check is the fuel pump relay in the front trunk. My mechanic suggested to check this as well when mine died. It is part number 911-615-108-01-M504 or 911-615-108-01-M253 here on Pelican.

[dtxscott]

An intermittent cylinder head temp sensor (or a bad connection at the plug) may exhibit the same behavior.

[E Sully]

If not the dme relay, I would check the speed and reference sensors. The DME will not turn on the fuel pump if it doesn't sense the engine spinning. You could also jump out the fuel pump and check the pressure.
When my car would't start it was my DME that was bad. I had it repaired and the jumper update done.

[kidrock]

car looks really great with the polished bar and new wheels. An H4 headlight upgrade will really finish off your look.

jumper your DME at the relay plug (#6 to #7) and listen for the whirr at the fuel pump. Whirr should be strong, not weak. I had a similar problem as yours and replacing the pump solved the problem.

The speed and reference sensors are also a possibility. I've never really figured out how to diagnose these...I don't have an oscilloscope in my bag of tricks. May just be one of those things where you replace them and cross your fingers?

[85Shark]

Thanks guys, the money I've saved on purchase I'm putting into new parts but that's ok. I going to start with another DME then jumper the fuel pump, and so on.

Stone your right in my power alley chrome trim ring and H4 are next on the list.

Please keep any and all ideas coming.

[steve911]

In addition to the DME relay, check the grounds in the engine compartment.
I had a very similar issue with my '85 last year. After replacing the DME relay and having the problem recur, found a loose ground. No problems since.

[Tim L]

I'm going to go with the speed and reference sensors as others have said; you can check the ohm's and compare the two for a quick check, they usually go to an open circuit when they go bad.

[85Shark]

Finally got a chance to take a look at whats going on, new parts in from Wayne. So here goes. Just by chance I tried to start it after a 8 day sit and she tried to fire, rough start but a start, but after about 10 seconds she shut down and I am back to the same problem. So another new DME relay went in and nothing so off to the fuel pump relay and then the fuel pump it self.

[Aurel]

I really hope there have been no 911s harmed during that stupid cash for clunkers campain. First of all, if the engine is running, any 911 is worth more than $4,500. Secondly, it would make baby Jeezus cry to pour sodium silicate in a running flat six motor, and should be considered a felony! Thanks for saving her.

To answer the question, is there a check valve on the fuel pump that could be bad? I do not know the 3.2s very well though...

[E Sully]

The DME relay is the fuel pump relay, but there is a 25A fuse. If you are getting a spark, the speed and reference sensors are ok.