please don't let it be the DME :(

[ritter4242]

hey guys..
So I have an 84 944 just got it back from paint.. and it was running fine.. right up until today. I turn the key, lights come on. Start the ignition, there is a light click/thump/noise, kinda sounds like the starter trying to engage then nothing. No power, nothing. it did this once, disconnected the battery, waited and reconnected and it started. Got it out of the shop, got the new car in and went to start it again, did the same thing, except this time it didn't start.. luckily its a light car so I got it back in the shop.. it about to storm here in Iowa.. any idea whats wrong? I really hope its not the DME.. /: I've disconnected the battery in case its something really bad, but my fingers are crossed..

[944 Ecology]

Check all of your grounds for tight connection.

Check the battery positive connection and the starter and alternator connections.

[John_AZ]

Check the charge on the battery. If the car has been in the shop long it may have discharged when interior lights/doors were left open.

DO NOT JUMP---take the battery out and charge.

If you jump with a dead or low battery you can fry the DME---or maybe it is too late....

GL
J_AZ

[ritter4242]

its not the connections, it started fine this morning when I took it out of the shop, its like the juice is going to the starter and then its blowing a fuse.. I disconnect and reconnect the battery and I've got power again but it the same story if I try and start it.. /:

[9FF]

The starter is a direct connection, there are no relays in that curcuit. If you have power to the starter solenoid when you turn the key and it will not turn chances are your starter solenoid is toast.

[jeffrsmith]

+1 on what 9FF said. If you are blowing fuses you either have a loose connection or you have have a bad solenoid.

[jhowell371]

Sounds like a bad connection, top side check battery cable clamps, battery ground cable to firewall connection. Love the vehicles in the background!!!!!!!!!! Studebusters drive me wild!!!!!!!!!!!! I used to have deuce and a half with a dump bed on the back and winch on the front, used it when I cleared my mountain side homesite. What a beast it was and built by Curtis Wright Corp. (Studebaker). Is the Studbuster truck bigger then a half ton? I can't tell from the picture.

[ritter4242]

I'll crawl under and see whats going on is there a write up on how to fix a DME?

and yes those are Studebaker I think its a 3/4 ton? not really sure, that m35 is also a Stude, my father collects them :P lol beautiful car too bad they went under.. well except the avanti

[djnolan]

Check the battery charge with a volt meter. If the battery voltage is below 12 volts it needs to be taken out of the car and charged. It should be somewhere between 12.4 and 12.8 volts after a full trickle charge, depending on its age. If it is below 12.2 volts or so after charging it is on its last legs. Once you have a good battery, if it still doesn't start, proceed to trouble shoot the starter, cables, etc.

[thom4782]

If it does turn out that it's the DME, you might check these guys out. They helped a Boxster forum member with his car's computer and imbolizer. Prices seem reasonable. They would be the first ones I'd call if my 986 DME goes bad. http://www.ecudoctors.com/

[VirginiaF1]

Originally Posted by John_AZ

DO NOT JUMP---take the battery out and charge.
If you jump with a dead or low battery you can fry the DME---or maybe it is too late....

GL
J_AZ

Howdy John..
Just to educate, why aren't modern cars' CPU fried when/if a dead battery gets jumped.. Thanks!

[jhowell371]

Originally Posted by ritter4242

I'll crawl under and see whats going on is there a write up on how to fix a DME?

and yes those are Studebaker I think its a 3/4 ton? not really sure, that m35 is also a Stude, my father collects them :P lol beautiful car too bad they went under.. well except the avanti

My deuce and a half was the M58 "Eager Beaver" series. The 1953 Starliner coupe was the best looking car of the 50's IMHO

[ritter4242]

Originally Posted by jhowell371

My deuce and a half was the M58 "Eager Beaver" series. The 1953 Starliner coupe was the best looking car of the 50's IMHO

land cruiser all i gotta say.. 51 I believe

[John_AZ]

Originally Posted by VirginiaF1

Howdy John..
Just to educate, why aren't modern cars' CPU fried when/if a dead battery gets jumped.. Thanks!

Hi Mikey,

I'll postulate.

The early Motronic DMEs had basic manufacturing flaws not found in later years & newer cars.

Poor solder flow, lack of circuit protection, component and circuit structure not designed for surge in amps+++ .

Water damage.

Just a few ideas.
J_AZ

[Gawernator]

How do you define "early" and "late" Sir John?

[John_AZ]

Mr. Gawer,

Sorry I was not clear.

VirginiaF1 asked about the "modern" cars and I should have been more specific than saying "later years" .

The DMEs in the 944 series from ROW '82 to '91 seem to be the most prone to failure or abuse by the owners causing failures. I would refer to these cars as the "early" series.

J_AZ

[ritter4242]

well gents its was the DME luckily I have a spare and luckily Specialized ECU Repair fixes them and they have a 5 year warranty