944 Not Starting - Has spark
 

Ok I have been diagnosing my no start issues.:
- Removed spark plug, when grounded I see a spark so I have spark
- I have voltage at the injector when the ignition is on
- I removed the injectors and put bottles on them, no fuel spray at all when cranking.
- Replaced the DME relay, no difference
- I see the RPMs on the tach bounce when I crank the car.

So, fuel pump dead? DME dead? Which is easier to test?

Thanks!

have someone crank it while you're in back by the fuel pump, so you can see if it's running or not. if it's not running, there you can jumper the dme/fuel pump relay to check if your fuel pump is good. that procedure can be found here: http://www.clarks-garage.com/shop-manual/fuel-05.htm. if it is running, your injectors could be clogged. if you have a guage, you can check the fuel pressure by removing the nut at the end of the injector rail. IIRC, fuel pressure should be a little over 40 psi (somewhere in that ball park.) if all else fails, depending on the year of your car, i might have a loaner dme, relay, and fuel pump.

hope this helped

There are several common failures for no start on 944: bad DME relay, bad DME, broken timing belt, reference sensors, bad alarm relay, and probably others I'm not experienced with.

However, as a general rule you need three basic items to start any car:

Spark, Fuel, and Compression (correct timing doesn't hurt either).

Check the easy stuff first:

Make sure you have gasoline in the car! I've seen this problem more than once.

Look through the access port in the very front of the cam tower to make sure the cam is turning while someone else cranks the engine. (Check to see if timing belt is broken/stripped teeth) Also check to see if the tachometer "bounces" while cranking the engine. (indicates the DME relay is working)

You already know you have spark so you can skip the spark test, but test spark in each plug

After cranking the car a few times, crack open the nut at the front of the fuel rail. Gas should spray out under high pressure. Tighten up the nut.

Open up the air cleaner and give it a shot of starter fluid while someone cranks the engine. If it starts, it points toward a fuel problem. If the starting fluid is successful and you actually get high pressure fuel spray from the test above, try using a BIG long screwdriver, hold it like a pool que and tap firmly but gently at the bottom of each injector.

Post your results for further help.

jmd_forest

Hi, have someone turn the motor over with you under the car with a volt meter at the 2 fuel pump terminals and see if you are getting 12 volts when he is cranking over the motor. You will only get voltage when someone is turning the motor over with the starter. If you are getting 12 volts from wires to the fuel pump and don't hear the fuel pump turning over than it is your pump. If you are not seeing 12 volts than probably your DME relay is bad.

Been there done that for this. Everyone has made some good suggestions. For testing the fuel pump though use the suggested proceedure on Clark's page.

Since your getting spark, but no fuel through the injectors you can pretty much isolate this to either fuel pump, fuel lines & filter, fuel rail or injectors.

Try disconnecting one of the injectors from the fuel rail. Make sure you have rags under it though. If even a little fuel comes out then you know your fuel pump is ok and fuel is getting to the injectors. If you get this far and it looks good, get a NOID tester. It goes between the injector cable & injector. It will light up if the injector is getting power when cranking. Believe it or not, the wiring harness for the injectors can/do go bad (ask me how I know). Easy to fix & cheap too. If you do get power then you know you have bad injectors. If you get this far let us know.

Witch Doctor is the best place to send the injectors to. they will not only test them, but will clean them and put new seals on them. I think they only charge $15/20 per injector but can't be 100% on that since I had them to mine last year. They are great to work with and pretty much turn them around the same or next day.

When was the last time it ran? Year of car?

Dal

Thanks for all the replies....

The car is an 84' 944 and I drove it last winter/spring frequently. I then got a nice boxster and sadly my 944 was a tad forgotten for about 6 months.

The timing belt does move in the cam hole access when I crank it, and I do get spark on all cyl. I get 0 fuel spray when I removed the injectors and put bottles on them.

I also just replaced the DME relay. I will check the voltage on the pump this weekend.

Hi there,
dont know if you figured out your no start issue yet, but I had the same thing on my 944S. It wound up being the ignition module even after i replaced it. had it tested along with another new one and they both failed even before pluged in. come to find out it only works for some models. Ordered a different manufacture, started right up. But, at least i now that EVERY thing else works great. Front driverside by your a/c sight glass on the fender well. If not yet fixed, they test em' for free.

different car 84 944, that module does not apply

So it looks like you've got it narrowed down to a probable fuel problem. Now to figure out just what the problem is.
1) No fuel - just add gas
2) no fuel pressure - as noted in my prior post crank over the car a few times and crack open the nut at the end of the fuel rail. If fuel spray out under high pressure, it's probably not the fuel pump. If no pressure, most likely the fuel pump or electric circuit to the pump.
3) injectors not opening - either they are not getting the signal (use a noid light per hpservertech post to check) or they are "bound up". I would try the tapping with a large screwdriver trick and if it works, dump a double shot of injector cleaner in the fuel tank.

Wasn't going to bring these 2 up yet but........... the FPR and dampener should be a consideration, but get the rest ruled out then look.

Dal

Thanks for the replies... I got back home and checked the fuel pump voltage on the 2 screw terminals on the top of it when cranking the car... 11.4 volts was my reading. I did not hear any noise from the pump, nor did I feel any vibration when I touched the pump when it was cranking either.

So, it looks like its the fuel pump then. It looks pretty old, I know for a fact its at least 13 years old and there is a very large probability its original.

Thanks all for the help!