enatera214

Hello everyone, I’m new to the Porsche 944.

I bought this 83’ 944 a couple weeks back. I replaced radiator hoses, distributer cap and rotor, spark plugs, speed/reference sensors, and a cracked vacuum hose under the intake. The car idles now, but barely. I don’t think it’s running on all its cylinders. Fuel pressure, compression and spark is all good. Starting fluid just stalls the car out. As you can see in the video, when I fully depress the gas pedal, not much happens, the rpm’s don’t increase, but the shaking becomes harder. I’m kind of stuck here and not sure where to go at this point. Any help is much appreciated, I can’t wait to get the car back on the road. From what I was told, it’s been sitting since 2014.

https://youtu.be/9olTan5BlF8

Dr. 914

make sure you have the firing order correct then pull one spark lead at a time from the distributor cap to make sure all make a decided difference. If one does not then that is the suspected cylinder
also make sure that you do not have any intake leaks

Gage

Some of the injectors are likely plugged, stuck closed or not receiving signal to open.

enatera214

Removing the spark plug wires individually doesn’t seem to do much to the engine. Maybe very slightly. I pulled the injectors off, cleaned them, installed new o rings, and reinstalled them. Still nothing. I’m hearing them clicking while the engine is running. I pulled the intake off too, noticed that the J shaped vacuum hose under it was cracked, and replaced it. None of these seem to have improved the engines condition at all. I’m really stuck at this point and not sure where to go 😣

Zirconocene

Well, I think it's time to go to the old standby and take a look at Clark's Garage. Go through the no start checks there systematically and see what you find.

As to the injectors, I know you said they're clicking but are you sure they're flowing fuel? There are cheap testers/cleaners on Amazon that use brake cleaner, a 9V battery, and a small electronic gizmo to cycle the injectors.

Good luck

enatera214

that’s actually exactly how I cleaned them. Connected 9v battery to the injector, and shot brake cleaner through them until they all had even spraying patterns

Zirconocene

TPS? CPS? AFM?

It sounds to me like Clark's procedure is the best choice right now. The good news is that, once you get it running, it's going to be sweet.

Good luck

Gage

Is the intake path clear? AFM door moving?

enatera214

yes, I took the intake off and inspected it. I replaced the J boot, vacuum hose, and tps while I was at it but still no change

enatera214

I replaced AFM and TPS while the intake was off, do you think maybe it could be the speed/reference sensors? That was the first thing I replaced on the car

Zirconocene

The reference sensors are insanely critical to everything. Even if they're OK, small problems in the harness could also make them seem not OK. So, maybe a little more fundamentally, have you checked the grounds on the car? Clean the connections with a little bit of abrasive, use a little bit of DeOxit, and reassemble, and take a good look at the wiring. On my '91 the injector connections were a mess. There were no problems but the harness looked like problems were on order, if you know what I mean.

Cheers

austin944

Check that the timing belt is not off by a tooth. Since you just got the car running, you don't know what the previous mechanics have done to it.
http://www.clarks-garage.com/shop-manual/eng-06.htm

enatera214

I hate to be a quitter but I just really can’t figure out the issue here. I’ve never been met with an engine this tough to get running.

Gage

I have not needed to do this but I have been intrigued by the descriptions here of removing the rail, complete with injectors, and placing a clear container at each injector. Watch for pattern and delivered volume while cranking. Might want to pull the coil wire and plugs.

enatera214

I'm still having the same issues. No matter what I do I can't seem to figure this one out. The car idles very hard, and when I press on the gas, rpms do not change, but instead the car shakes more violently. I noticed the o2 sensor was disconnected. I plugged it back in and now the car idles for a few seconds before it dies out. I have to keep my foot on the gas to keep it from dying now. I'm really not sure where to go from here. I appreciate all your help but I feel like I'm stuck. I changed the distributor cap and rotor, wires, spark plugs, cracked vacuum hoses, DME relay, speed/ref sensors, and fixed some other smaller things. The car has been sitting since 2014. I drained the gas tank, cleaned the strainer, filled with new gas, and jumped the DME to run the new fuel through the lines. I appreciate any help and will try any tests anyone has for me.