Or was it a coincidence?

let me 1st note that i am not at all tech savvy, but have gleaned some basic ideas from this board & pelican... <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />

Over the past 2 or 3 years *&lt;3,000 miles /year*, my 86 911 has had 3 or 4 'no start' episodes. Following one at a DE in october, where turning the key, led to buzzer & idiot lights but nothing else - fuel pump? maybe - i was able to push start it * a DE is the best place for a no-start , of course - lots of help & sympathy! car had been running fine*. got it all the way home w/o stopping - went to start it 2 weeks later, no problem and OK for a few times after that. The wrench took it for a long time, and ended up changing the 'wiring' - i understood that to mean to the plugs etc. - $$ - they were old & cracked, tho
Comes the spring, car comes out - started and stopped many times in the past few weeks to get washed & driven...No problem, stopped worrying about turning it off.

So, yesterday AM, i go for a ride on the Palisades, take the top down , and decide to clean out the car & straghten up at a rest stop - in doing so, i mucked around behind the drivers seat, where i park a small umbrella.
Started up no problem, drove home, parked in front of my building *you NY'ers understand, alt. side of the street parking, and its implications for an immobile vehicle*, went to get my bride & take her for a ride in my gleaming, humming, cabriolet...and - NO START!!&*^%$! <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" />

one cannot really enjoy any car if youre never sure if it'll start or not

Anyway, I had recently downloaded a flow chart for electrical problems from this board or pelican - took it out, & really there was not much i could do or even understand - but it did say check the DME & relay - so I jiggled some wires & checked the connections in the back & front of the DME box & ignition, esp. thinking I might have moved them with that umbrella.
W/O real hope, I turned the key, and - HOLY S**T - it started!! at first, i couldn't believe my ears! <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" />

ran fine. and started up again on the way home - tho I did park it on top of a hill).

Well, my wife thinks I'm very cool (well, for a moment), but do you guys think I actually did any thing? Would a faulty DME allow a car to be pushed started? are there wires in the back of the DME from sensors that could be loose - i do carry a spare DME, but the problem happems so infrequently, that consistent starts might not really prove anything...

Sorry for the long post - thanks in advance for your advice <img border="0" alt="[byebye]" title="" src="graemlins/wave.gif" />

Fred L.

 

Fred,

My hunch is your problem is still lurking...sorry.

You could certainly double check your DME connectors by removing them from the DME CPU box and the DME Relay. You can inspect the connections for loose or broken wires. I have seen a continunity check process (using a ohm meter) for the pins on the DME cable, but I do not have a copy.

When you have your problem, it sounds like the car's electrics come on, but the engine will not crank. That sounds like an electrical problem. Could be dirty battery terminals, loose or dirty connections to the starter or bad grounds. Check the ground from the battery to the body (remove and clean) and check the ground strap from the tranny to the body (difficult to remove and clean, but doable). Make sure your connections to the starter are clean and tight.

On the other hand, if you car turns over but doees not start, the first thing I would suspect is the DME Relay.

The 3.2 Carreras are very prone to problems caused by bad (i.e. dirty) electrical connections and grounds. That is where I suspect you will find your problem.

Bruce
'84 Carrera
'77 911 (Euro spec)

 

If it is happening when the motor is hot, your starter may need to be rebuilt, or, the transmission ground strap may need to be cleaned and tightened.

 

My 78 SC did that only one time. Turned out it was a "loose" fuse holder "clip". The fuel pump requires a very high surge current and apparently over time that had over-heated the fuse holder clip causing it to lose its "spring".

Fuse was in place and visually there was absolutely no indication.

 

Thanks guys for your quick & thorough response -
Bruce, I think you are right that I didn't really do anything - I now understand between you & the wrench that if "it cranks but doesn't start", thats a good indication of DME problems.
It didn't start again yesterday morning, and then after push starting started up several times no problem.
FWIW, the wrench checked all connections last time - he will put in a rebuilt starter (at a reduced price) - he thinks it must be either that or ignition switch but thinks the starter is more likely -
I will post an update if any useful info -
thanks again -

and happy spring/summer driving to all

 

Jaws911, if the DME relay is bad, the car won't start at all. Sometimes they are intermittent, but mostly they fail instantaneously. I was on a trip going about 75 mph and the car died as if the switch had been turned off. I thought I had a fuel problem. I let the car sit for about 10 minutes and fired her up. All was well for about 10 miles, then she shut down completely. DME was intermitent the first time, but shot on the second try. Replaced it and all was OK. I now carry a spare in the glove box of my 88 Carrera.

 

Spider 911-any good sources for DME relays? I would like to buy a spare for my glove box too!

 

Just a follow up, to add a bit to the collective knowledge on this BBs - shortly after the original post (4-21-03) , I had the starter replaced - tho I didn't use the car as much this summer as in the past, due to the lousy weather, i haven't had a problem since - I think it was the original starter that was the replaced, BTW.