Poor running 944 na

Dvandy1 · 08-19-2008, 09:18 PM

I recently purchased a non running 87 944 with a blown head gasket for $500. I put in a new gasket had the head milled and replaced the timing and balance belt while I was in there also. I finally finished it and got it running, but it lacks power and is hard starting. I rechecked the timing belt and the cam sprocket lines up with the housing and the window on the flywheel that says OT with a line above it so I don't think thats the problem. Any direction or guesses would be greatly appreciated

hpservertech · 08-19-2008, 09:32 PM

make sure you reconnected the tps and the afm. Then look for vacuum hoses disconnected/missing.

Also read through www.clarks-garage.com

m73m95 · 08-19-2008, 10:23 PM

Did you check the compression after the new head gasket?

If you have a broken ring(s), or the engine is just worn out, and the rings don't seal anymore, then it will do what you're describing.

The problem with getting the new shaved head is you've created more compression. The valves seal better (as thier new) and the head is milled (though, I'm sure its just a tiny bit). Now you've got great compression on worn out rings, and once they let a little of the intake charge get by them, the rest will slide by without a problem...meaning very low compression.

Do a compression test 1st, then go from there....also, you can pull the oil fill cap off while its running and see how much oil vapor (looks like smoke) comes out. If it looks like smoke from a fire, your rings are gone.....

earlr85944 · 08-20-2008, 05:38 AM

check for clogged injectors

Dvandy1 · 08-20-2008, 07:38 AM

I did a compression test and it was 150+ psi on all cyl. I also did a fuel press check and it was about 40 psi running. I did notice however that as soon as the car shut down the press went to zero in about 10 sec. On most of the cars I've worked on they hold the pressure is that true for this engine?

hpservertech · 08-20-2008, 08:31 AM

No it should hold it and then slowly drop it over 20 minutes.

Again, go through www.clarks-garage.com, this is on there as well as the results you should see.

speedracing944 · speedracing944's Garage

Are all the vacuum lines hooked up?

Speedy

earlr85944 · 08-20-2008, 09:43 AM

you have good pressure but may have clogged\leaky injectors
best to do a visual on the spray pattern

Slam · 08-20-2008, 11:43 AM

Fuel pump, fuel filter, fuel pressure damper and regulator? Just off the top of my head...

Dvandy1 · 08-20-2008, 06:53 PM

Ok thanks for all the suggestions, I'm calling this project now a complete success. I lightly tapped on each of the injectors with a long screwdriver and a mallet and what happened....the thing started idling great and the rear exhaust tube started to burn of the gunk that was dropped on it during the project so it must have been the rear injector. I guess you can still fix things with a hammer. The only thing left to do is loosen up the balance belt a bit and get a new upper radiator hose since I didn't notice it was rubbing on the alternator pulley during my celebration dance when I got sprayed with coolant.........not as refreshing as a Gatorade bath but what the hell. Thanks for all the suggestions, they were all hinting at the same thing.

MixMasterK · 08-21-2008, 11:18 AM

Make sure the front end hasn't been in a collision. My '83 that I have was in a minor trailer wreck that pushed thefront core support backwards. It causes the coolant hose to rub on the alternator as you described. Core support and front end has been pulled on a frame rack to specs, but needs to be replaced.

Of course it could just be that the adel clamp on your hose near the alternator is not situated correctly....or is it even on there?

m73m95 · 08-21-2008, 12:24 PM

Check ball on the fuel pump.

They go bad and let the fuel pressure off. Its simple to get to and replace....and cheap too