924Board.org

Joe549 · Posted: Sun Dec 21, 2008 11:07 am Post subject: Why wont it start???

1987 924s, 2.5l 4cyl

The car won't start... it was running and starting fine yesterday, and now it wont start at all. The only thing I can possibly think of is something is frozen... we had a severe change in weather yesterday with high winds and blowing snow.. There is gas going to the cylinders, the plugs have spark and have been pulled and cleaned and re-gapped. The engine turns over and sounds as though it wants to start but wont catch....... what else can possibly be the problem?

John_AZ · Posted: Mon Dec 22, 2008 3:01 am Post subject:

Change your DME/fuel pump relay.

OR

With the key in and turned to start engine, does your tach bounce a little.
It should. The starter spins the flywheel and the reference sensors will cause the tiny tach bounce. If no bounce, the reference sensors may be your problem.

First check the cable connection at the back on the engine top firewall. Clean pins and maybe put a dab of dielectric grease in to prevent moisture from coroding contacts.
Check the wires-any frayed or cracked?
Its really cold but you may need to regap. See www.Clarks-Garage.com

GL
John_AZ
1988 924S + 1987 924S DD

Joe549 · Posted: Mon Dec 22, 2008 7:23 am Post subject:

Both the sensor relays are new, the fuel pump seems to be working, there is fuel going to the cylinders, I've regapped the plugs to 0.30mm and still not getting anything. I pulled the plugs last night cleaned and dried them and left them out over night to allow the cylinders to dry out of gas as it was flooded pretty bad. Put the plugs back in this morning and tried and still won't start....

John_AZ · Posted: Mon Dec 22, 2008 7:36 am Post subject:

Still could be the DME relay. Controls the computer and the fuel pump.
See: http://www.clarks-garage.com/shop-manual/fuel-05.htm

There is a no start section on www.Clarks-Garage.com as well.
See also: http://www.benms.com/techinfo.html

GL
John_AZ

Joe549 · Posted: Thu Dec 25, 2008 10:29 am Post subject:

well still not entirely sure what the problem was..think something might have been frozen..... car was towed to the mechanics and sat in his lot for almost 2 days before he could look at it. He tried to start it and the same thing happened, he put it inside the garage overnight, put some gas line antifreeze in, came in this morning turned the key and it started... all I had done was an oil change. He suggested that with the weather going the way it is lately just to put a bottle of gasline anitfreeze in once a week...

D Hook · Joined: 02 Nov 2002 Posts: 3158 Location: Omaha, NE

Do you own a spare DME relay?

If not, here's an option:

http://cgi.ebay.com/ebaymotors/DME-Fuel-Pump-Relay-Porsche-911-924-944-968-S-Turbo-NEW_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1205Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a0Q7c293Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem390019214224QQitemZ390019214224QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

No affiliation, yadda, yadda.....
_________________
'80 924 n/a SOLD

John_AZ · Posted: Fri Dec 26, 2008 3:56 am Post subject:

Joe549,
Thanks for the feedback. I should have seen you are in Canada and at least suggested that cause. Canada supplies 10% of the US gas supplies but I have read from other Canada members stories of low octane, poor mileage and your symptom of moisture in the tank.
It might be a good time to change the fuel filter.

Glad you now know where to begin if it happens again.

GL
John_AZ