yet another starting problem

newoldguy · 03-03-2006, 03:53 PM

No starting problem, will crank but not fire up. Suspected the fuel pump relay as it is often the culprit. So I made the "Y" jumper as suggested in Clark's Garage. Plugged into #2, 4, and 8 in the fuse block and BINGO, she fired right up. So, I ordered a couple of new relays (one for a spare), went out and plugged in the new relay and NOTHING. Put in the "Y" and it started up again. So, its obviously not the relay at all. Now what??????? Has anybody had this experience before? Thanks in advance for the input.
Curtis' '87 944 n/a

bigbird944 · 03-03-2006, 04:13 PM

I duno thats quite odd. Do you have spark when you have a good relay in there?

SoCal Driver · SoCal Driver's Garage

Depends on what pins 2, 4 and 8 are.

Here is the page at Clarks.

http://www.clarks-garage.com/shop-manual/fuel-05.htm

There are two sources of power for the relay. You should be using pin 86 as the power source rather than pin 30. This will test the ignition switch power. The other ends into 87 DME and injectors and 87b fuel pump.

Note that when you use the jumper you are bypassing the alarm cut off. This could be an alarm problem.

BananaClip · 03-03-2006, 06:28 PM

might be the slots in the board. I believe people on here have had problems with the prongs on the relay not seating right.

I have a feeling socal is right though. He usually is!

Jer944 · 03-03-2006, 07:55 PM

the fuse block gets very dirty all the time try cleaning it with a small pipe cleaner or somethen in order to get rid of the muck that built up due to the different metals used

newoldguy · 03-03-2006, 08:38 PM

OK, here's some more specificity. I did use the Clark's technical info and testing article. He suggested jumpering: 87 (which is #8 and powers the DME and injectors), 87b (which is #4 and powers the fuel pump), and 30 (which is #2 and gives batery voltage. In the article, he suggests "I strongly recommend using terminal 30 (#2) instead of terminal 86 (#3, Ignition switch)".

Therefore, SoCal may be on to something since I did NOT check the ignition switch pin. I believe this is one of the "small" pins on the bottom of the relay and I will have to fabricate something to work with the jumper wire. The three slots I used are the "big" female ones in the fuse/relay block.

In any event, I guess what you are suggesting is that the problem could be in the ignition switch? I will go visit the car tomorrow and check with the other pin and get back to you guys.

Oh yes, and unless I'm totally ignorant (lately a distinct possibility), I don't believe my car has an alarm--either factory or aftermarket.

SoCal Driver · SoCal Driver's Garage

Quote:

Originally posted by newoldguy

Oh yes, and unless I'm totally ignorant (lately a distinct possibility), I don't believe my car has an alarm--either factory or aftermarket.

That eliminates a sometimes PITA problem. As noted above the sockets in the relay base can sometimes be sprung and not return sufficently to contact the pins on the relay. As to making a jumper; use an old relay base.

In many cases I disagree with what I find on Clarks. Then I do find solid info there too.

newoldguy · 03-04-2006, 06:46 PM

Here's the latest update:
Car won't start
Bought new relay, still won't start
made jumper and connected 30, 87 and 87b
car started!
put in relay just to check, still won't start
SoCal suggested jumpering 86, 87, and 87b
car started!
put new relay back in just to check, no start
So what the heck is up with this? Car will start with jumpers from either battery power or ignition switch but NOT relay. I'm sure anxious to hear from someone what is wrong with my car.
Curtis' '87 944 n/a

SoCal Driver · SoCal Driver's Garage

A quick test:

With a DME relay in the socket turn the key on and see if you have voltage at the injectors. If not then the DME relay is not seeing the first level power from the ignition switch. Which means the base sockets are not contacting the pins on the DME relay because you can put your jumper in and run the car.

I know this to have happened before.

newoldguy · 03-05-2006, 09:13 AM

SoCal - Thanks for sticking with me on this problem. What is the process for making the base contacts "work"? Can you stick a probe in there and bend the contacts? Or do you stand the risk of making it worse? There's gotta be a way to make the base contacts make a better connection. I think this is what you are diagnosing.

SoCal Driver · SoCal Driver's Garage

The fuse/relay block can be dissassembled. There are a couple of retaining bars on the underside. Have to pull it out. Disconnect the battery first.

Then you can pull the individual mount out for the DME relay to get at the sockets.

Brandon has taken his apart recently so maybe he can jump in here with more detail.

SoCal Driver · SoCal Driver's Garage

Here is the bottom of the fuse/relay block for the later cars.

The arrow points at the locking gizzmo.