Newbie here 911 dies then won't start

01sport · 12-04-2006, 10:49 AM

87 Carrera 40k.

Hi I am a newbie here. My car intermittently will not start. Won't start for days then it starts right up. Started up yesterday then all of a sudden died. No sputtering, just dies then will not start. Car turns over and smells like gas. Fuel pump fuse O.K. Did some Searches on some forums and installed new DME relay which did not fix the problem. Yesterday, after it died, I reached under the seat and banged on the Motronics box and it started right up. Thought I'd post a thread and see what you guys think before I crack open this Motrincs box to look for cold solder joints. Is there anything else I should look at first?

Jeff · 12-04-2006, 11:50 AM

Could be a broken solder joint in the DME. I would start by checking your Speed sensor, Reference sensor and Cylinder Head Temp sensor. The y are on the left side of the engine bay (when looking in from the rear of the car) on a vertical stalk. Check them for cracks in the wiring, if they are caracked replace them. Also if the CHT is the old 1 wire unit replace it with the new 2 wire one. I don't have the specs for testing and gapping the sensors infront of me, hopefully someone else will chime in.

If you get to the point of removing you DME box, look at the wiring under your seat, mine was pinched and shorted (armed) my alarm and would not start.

Welcome to the board!

xlr8 · 12-04-2006, 12:12 PM

Link to Motronic DME troubleshooting thread.

Good luck!

01sport · 12-04-2006, 03:02 PM

Thank you for your replies. Is there a 911 D.I.Y. board that you know of? I have a BMW E38 and we have a E38.org board with hundreds of projects for the novice DIYer. In lieu of online instructions, what manual would you suggest I purchase for my 87 911?

Jeff · 12-04-2006, 03:11 PM

This is a 911 DIY board. There are tech articles on the main site. The manual by Bentley publishing is the best. Also get 101 projects for your 911, sold here and written by our host.

01sport · 12-05-2006, 09:44 AM

Just got through resoldering the cold solder joints inside my Motronics DME box. Three bad connections right where you said they would be. Will not be able to confirm problem by installing box in the car until tonight but confidence is high. Thank you C U L8R and xlr8 for your help. Guys like you make this a great Board.

Jeff · 12-05-2006, 12:10 PM

Keep us posted on what happens. Others may be chasing the same problem.

Now you need to post pictures of your car. It is kind of a right of passage around here.

01sport · 12-06-2006, 06:28 PM

Car starts. I think we nailed it. Thanks again. BTW my car burns oil on start up(white smoke that hangs in the air). It has been suggested to me that the seals are bad. The valves are pretty noisey as well. Any thoughts?

BReyes · BReyes's Garage

have the valves adjusted. Can ask them to do leak down/compression tests. Post the results. Some guides probably could probably be replaced.

Regards,

T77911S · 12-07-2006, 03:50 AM

what i have noticed with mine is when i start it up, there is no oil in the tank, so it must be in the engine. it leaks past the rings and burns off when u start it. as long as it doesnt smoke all the time or when u really get on it, i wouldnt worry. the oil doesnt start pumping back into the tank until it reaches 125* temp. then it only does it at idle. once i hit 170* then it starts keeping oil in the tank. i think some of the smoke is normal. white? i thought the oil would be blue. i blow a nice cloud myself, but i think it is blue. i have very good compression, all right at 165 with 94k miles.
valve seals i think u would notice burning oil when u let off the gas, the increased vacuum sucks oil in past the seals. if i am wrong, someone speak up.