jeanmarcboilard

Wow, that's a lot of work and very good trouble shooting in only 10 days, congrats on the car and the progress so far. Sounds like you shouldn't have much trouble getting it on the road now.

944 porsche

Day 12 of ownership...

Cleaned injectors and it fired up! It ran a bit rough at first but idled fine after a few minutes (see video below). Just took a few minutes to wake up after a 5-10 year nap.


Didn't have time to address the seized clutch master today but I'm not going to put it off since that's the only thing keeping me from the first test drive!

944 porsche

Clutch issue was just seized linkage. Took my first brief test drive yesterday. Idled very rough, and pinpointed it to a large vacuum leak in the ISCV to manifold vacuum hose. New hose on its way.

In the meantime, will be working out electrical issues. Currently have all gauges except fuel and temp. Something in common is likely not right, maybe a common ground point.

FlyBoy1986

Nice find. good looking car. sounds like your having fun with it. looking forward to hearing how it drives when you get that far.

944 porsche

I received the new vacuum hose on Friday and reinstalled the intake. Started right up idled great and drove fine. The brakes were a little weak so didnt get up to speed. Probably just need to be disassembled and greased. The calipers looked pretty rusty.

The next day though when I went to start it up I got no spark. I went back through the ignition checklist and everything seems to check out. Cleaned all grounds just to be sure. Reference and speed sensors are okay by resistance. New dme relay. Coil generates a spark when grounded manually. One thing I have noticed though is that my voltage reads very low on the dash. Good voltage at the new battery but less than 10 volts reading on the dash. I'm thinking that the DME may not be getting sufficient voltage. That's what I'm going to check today. I'll try to walk it back from the battery and find out where there's a voltage drop. Has anyone had any experience with low system voltage even with new battery and working alternator? I'm thinking bad wire/connection somewhere...

Also, we just move to Dayton Ohio yesterday. Jeep towed the car well for 10 hours. Any 944 enthusiasts in the area?

944 porsche

So no voltage drop at DME. I decided to remove the aftermarket alarm to clean things up an just to get that off the list of possible causes.

Not getting tach bounce but sensors check out good by resistance. Have a new sensor on the way today that i will try anyway since one is still original or at least 10 years old.

944 porsche

Still battling a no spark condition. Seems to me that it is the DME at this point. Would love to find that it is something else but everything else checks out.

I get spark by manually grounding pin #1 at the DME plug. Therefore coil, wires and plugs are good. Also indicates power to coil and intact coil ground lead to pin #1 at DME plug.

If I am understanding the ignition system correctly all that I need is for the DME to ground pin number 1 when spark is called for. That should happen if the DME is getting correct input from the two sensors which are both new and bench test correctly via tests at the dme plug. So the harness is working as well. (I have tried the three plug dme relay jump wire to remove that relay from the equation)

Also cleaned all ground points.

If I am missing something please give me another lead to track down, but at this point it must be the DME. I opened it today and reflowed many of the solder joints with still no spark. There were no obvious defects on the boards. Now i want to trace the ignition portion of the dme and find the defective component. Does anyone have dme schematics online? I searched but the links to the944 website seem broken.

mel_t_vin

If you have not already done so, why not identify your location and ask if someone nearby would be kind enough to let you borrow an early DME?

944 porsche

I'm in Dayton Ohio. If anyone has a DME that would work in an 85.5 model year na 944 that I could try to swap in let me know.

In the meantime I think I may try to replace the transistor on mine.

944 porsche

I replaced the transistor and still no spark. Without any way to test the DME here at home, I decided to send it out to ecu doctors in Florida. I saw good things about them on this board and so far their service has been great! They received it today and within a few hours they confirmed my suspicions, bad dme.

I gave the go ahead for the rebuild as well as adding a performance chip while in there.

Should have the finished product early next week.

944 porsche

Got my ecu back from specialized ecu today. Expensive, but i recommend them.

Plugged it in and it worked perfectly! Finally getting to drive it to work tomorrow.

mel_t_vin

Nice. Happy motoring...

944 porsche

Thanks Melvin! I've been driving to work every day and it is happy motoring. Almost wish I had a longer commute!

944 porsche

Continuing to daily drive to work, but experiencing only manual braking. Vacuum is good to the booster but no power assist. Looking at doing new brake booster, brake master, clutch master and fluid while in there.

What does the small vacuum line going to the booster do? If the check valve is bad would i lose all power assist?

944 porsche

So much fun to drive! Tired of taking it easy with only manual braking so placed an order for new ATE brake booster, ATE brake master, booster check valve, clutch master.

Also got a new voltage regulator to try to silence some squealing that I have coming from the alternator area. Belts seem tight enough but I still get a squeal on start-up. I'm thinking it's old brushes on the regulator. We shall see.