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rutles 03-26-2003 05:01 PM

924 turbo won't start in morning
just bought a 1980 924 turbo , won't start in the morning ,or the first start of the day . the only way i can get it to start is to pump the disc in the air flow meter, then afer you do this many time it will start and keep starting until you let it sit for a while . does anyone have any ideas?????????????

drew1 03-26-2003 06:24 PM

acumulator? good way to check it is see if gas comes out when you take the screw out of bottom.

welcome to board.


Buddy 03-27-2003 01:29 AM

Have you bought a Haynes yet? There may be a check valve in the fuel pump that's not working right.

Check on the [url] There are several 931 owners over there very knowledgeable on the 931. It's the best site to be on for 924/931 issues. Should be able to help you out.

rutles 03-27-2003 07:26 AM

thank you for your helpful advice , one thing i left out was that this car was stored for a while and the gas has gone bad , i pumped out as much as i could and refueled with good gas and fuel injection cleaner , i'm not sure if this caused my problems or not . again thanks for any help SmileWavy

Z-man 03-27-2003 07:29 AM


Das only in da mourning, ya 'supozed to up up cookin breafast for somebody: it's like an alarm clock. Whoo whoooooo!

-Bubb Rubb
Sorry, I couldn't help myself! :eek:

Seriously: check the contacts on your distributor cap, as well as the wires and spark plugs. Also: in what condition is your starter? You mention the AFM: could it be malfunctioning? Are your injectors clean (931's have injectors, right?) if they car clogged, the residue can build up overnight as well.

Good luck! (Sorry about the quote!)

drew1 03-27-2003 06:41 PM

If gas cranks it after mashing the flapper, it is probably good enough gas to crank cold.

If no gas comes out the screw hole in the accumulator, check the 5th injector. It is toward the firewall on the manifold.

Ohm it out, if circuit open, it's bad. With the 5th injecvtor pointed into a container to catch the gas, have somebody crank the motor over. You should get spray.

If you don't, then unplug the 5th injector. Put a test light or volt meter accross the injector wire terminals. Crank again. You should have volts initially for up to 10 or 12 sec. If it doesn't then either you are not getting the 12V from the solenoid or thermo switch is bad & not grounding the injector coil.

hope this helps.

Thermo switch is kind of under distributor on the hose housing on back of head.


rutles 03-30-2003 07:24 PM

was working on the car today , someone had suggested that i check to see if the fuel lines going to the fuel distributor were plugged ,so i loosen them , pressure came out , now i cant seem to get presure back , before i had to pump the flapper by hand when the car was cold to get it started noe the flapper has no pressure behind it ,car will not start , but if i put some gas in the air flow meter where the flapper is the car will run until the gas is gone . does the fuel pump kick on with the key in the on position??? or does the car have to be started . iwas thinking the problem could be the fuel pump ??????

Roger Hall 03-31-2003 03:28 PM

Check the fuel pump output by pulling the return line and cranking the car for 30 seconds. Output is 1050 cc's per 30 seconds I think, but the 931 is different from my 924. Make sure to groung the coil wire so the engine wont start. If there is no fuel comming out remove the relay and jump the connections. It more likely to be the relay than the pump. Some guys carry an extra relay in the glove box its a common problem.

drew1 04-01-2003 06:31 PM

The fuel pump is running with just the switch on. It has to be cranking or you can pull the relay & jump terminals 30 & 87 in the socket. Using a jumper, made out of at least #12 wire & a couple spade terminals, is how I test the fuel pump flow & system & control pressures.

From the fuel pumps, you have a check valve on the outer pump, and a accumulator in line to the filter & fuel distributor. What happens when you crank is the pumps run, the thermo switch runs the 5 th injector for a short period if you're cold, & the warm up regulator drops control pressure to richen up the mixture. If you don't have enough difference in system pressure & control pressure you get no fuel through your injectors.

What can happen to hurt cold cranking is bad check valve letting gas run back through the tank when pumps are off. This would probably hurt warm cranking too. The accumulator could be bad. This holds gas under pressure to help warm & cold starting by holding gas under pressure to keep the pressure eqaulized & some in the line to fuel distributor. It is easy to check, just take the screw out of the bottom & see if you get gas meaning its bad. When you work the flap, you drop the control pressure making the ratio of what system pressure you have to control pressure high enough to send fuel through the injectors. This could indicate either the check valve or accumulator. You really need a guage to see if you loose pressure quik (it's bad) when pumps are off to check the check valve.

Sionce you already had pressure in the lines, the accumulator & check valve may be good. If you're pretty sure about this you need to check the 5th injector setup.


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