Another "It won't Start" Post!

gt350mike · 10-26-2002, 12:57 PM

We (my son and I) bought an 87 944 n/a and we were told that it was ran REALLY hot before it was shut down. He tried to start it the next day and it would not start. Two years later, we buy the car and before I tear into the motor, I wanted to start the motor so I'd have a better idea of what needed repairing (it could be as simple as a head gasket). We've planned worse case and that the motor would need a complete rebuild. If we were lucky (I'm sure not planning on it), we could get off with replacing the water pump, both belts, and maybe the radiator.
I have checked the oil (no water), the plugs (no unusual color), the fuel (fuel rail has pressure, but not sure how much). Before we tried to start it, I sprayed WD-40 in each cylinder, then sprayed a LITTLE starter fluid (SF) and the motor respond to the SF but would not continue to run. So it seems that I have spark and the fuel is in the rail, but could it be the injectors and/or something electrical from the rotor to the plugs.
I have search the forum for something similar to my situation, but nothing seems to jump out at me. I would GREATLY appreciate anyone's help/suggestions.

Thanks!

SoCal Driver · SoCal Driver's Garage

Check to see if there is 12 volts at the injectors with the key on.

Check to see if the fuel pump is running while you crank it.

If both then the DME relay is good.

If no to either then replace the DME relay.

You can test the fuel pump by jumpering between sockets 30 and 87 where the DME relay plugs in. This will run the fuel pump with the ignition key on. Socket 30 to 87b will provide power to the DME and thus to the injectors.

Since you remark that it tries to run when you prime it but dies; I'm thinking that the fuel pump is not continuing to run after it fires -- DME relay OR the speed sensor.

gt350mike · 10-26-2002, 01:28 PM

Ok....Just did the "rag tied to the extension soaked with gas" trick and the motor fired right up! I'm going to my Haynes manual to find th DME relay so I can jump between 30 & 87 to see if the fuel pump is working.
If the pump is working, then what is next? Do I check the DME relay to determine if it is good and/or how do I check the speed sensor?

The way it looks right now, the only think I'll be replacing (major end items) is the water pump and both belts. Relays and sensors are cheap compared to an overhaul! I hope reality doesn't shoot me; I'm hoping that we're lucky for a change!!!

Thanks SoCal!

todwic · todwic's Garage

From what you describe, the speed and reference sensors (on the bell housing) are working ok, and your DME is fine. If you have fuel pressure, and it runs with the gas soaked rag, then you either have a collosal vaccuum leak, or your enjectors aren't working/clogged. When the P.O. overheated my '44, he warped the head. that would acct. for a leak. There is a thread not too awfully long ago about someone having this same problem,fHere's one and another and another. there quick ones I came up with with the search "car won't start". I hope they have some info you can use.

gt350mike · 10-26-2002, 03:46 PM

I'm calling it a day while I still have my mind. I'll check the fuel injectors in the morning to see if there functional.

The idea of a vacuum leak really has my attention for the simple reason that you told me about your PO warping your engine's head. If the head is warped, wouldn't I have water in the oil or oil in the water? I'll check the vacuum lines but I hope my problem(s) is related to the fuel injectors.

Now I'm going to watch Alabama Kick Tennessee's A*s!

todwic · todwic's Garage

Maybe, maybe not, depends on where the leak is. You could have coolant leaking thru the intake valves, too. When it ran, was there any white smoke (steam) comming out of the tailpipe? You cold do a leak down test to see if you have leakage.

gt350mike · 10-26-2002, 05:40 PM

The engine ran fine as long as it had a gas soaked rag in front of the AMF. There was no smoke coming from the exhaust. I'll see if I can get a Comp. test guage in the morning.

Thanks!

951carter · 10-26-2002, 09:00 PM

After 2 years you should drain the fuel tank and put in fresh fuel. I went through 3 fuel pumps by forgetting that step on a restoration once =0

Do that first and then check to make sure your fuel pump is working and your injectors. All that stuff is probably "gummed up".

You can jumper the fuel pump as fore mentioned and also check the fuse.

You can pull the fuel rail, leave the injectors in it and crank the engine to see if all the injectors are firing; make sure you put a catch tank under them though =0...........cut down 20oz. soda bottles work great!

edit: I would change the fuel filter also!

todwic · todwic's Garage

Sage advice, Carter!