Ricardo Vega II

Hey guys, its me The Rookie. Well, after reading over all of your suggestions from my previous posting labelled, "1987 Porsche 928 S4 That Doesn't Start"I tried as much as I could of the suggestions that were submitted to my posting and the following is what I got. To refresh everyones memory the issue is that the car doesn't start but I have pressure to lines, as far as I know. I do have spark out of the plug wires. The timing belt is intact since it does spin when its cranked over, as seen thru the small holes where the air intakes are mounted.
I did swap out the relays and test them with the horn. My horn works so that relay works which is XII, I put the relay XVI for the Fuse/EZK Ignition System in place in the horn relay holder and then honked the horn and worked, put relay XX in place of the horn relay and that worked. Put relay XXV in horn relay holder and that worked too. So all 4 relays worked.
I did also check the voltage of the ingition and I have video and I only get 1.5 volts when its cranking. I did also get video of instrument panel when its cranking incase anyone wanted to see if there was anything odd but there wasn't.
One last thing I did resort to was using ether/starting fluid and that didn't even work! At this point I'm stumped..........what else can I possibly check?

Here are the links to the videos.




Ricardo Vega II
Broken Black 1987 928 S4

Mrmerlin

what was the last thing you fixed?

elgreco

Pull the upper covers of and check the timing marks. Make sure the timing belt marks are correct.

NoVector

Mr. Speake has a diagnostic test on his website which has some stuff that you haven’t said you’ve tested—like are your injectors clicking when you’re not cranking the engine and have you jumped 30-87 on the fuel pump relay instead of just swapping relays, etc. Here’s his website:

http://www.jdsporsche.com/fault%20find.html

I also found a lot of good information on this webpage on other things to test. In fact, I’ll be going through these today trying to fix my no start.

http://jenniskens.livedsl.nl/Technic...4/MyTip461.htm

Think your tach should bounce a little during cranking from the RPM sensor, but getting spark makes me think your EZx is happy with what it’s seeing from the RPM sensor. Here’s a short guide on testing the RPM sensor with a volt-ohm meter; but to really test it, need an o-scope.

http://jenniskens.livedsl.nl/Technic...4/MyTip461.htm

Trust me, I feel your pain... Good luck!

Landseer

Ditto on timing, but you should be able to do it with flashlight without removing covers. Set harmonic balancer to O/T, look for notches at back of cam gears, if none, rotate crank once, back to O/T and look for notches.

How did it act when you jumpered all three relays at the same time (fp, ez, lh) and tried to start it with foot on floor in 15 second increments to defeat a flood condition?

Did you see any corrosion with mirror and flashlight looking into coil ends? Are the coil wires possibly arcing out?

Rotors and inside distrib caps clean?

Grounds clean at back of engine valley? Those are for the electronics. Connectors for MAF and CPS in that same vicinity in good shape, no shorts?

Battery charged fully (If low like in video, can turn the car over, but lack power to fire)
New groundstrap?

If no start, I'd pull the CE panel, polish, re-fuse and inspect back for subtle wire melts.
Also, would then replace CPS proactively, regardless of tach bounce. That is a false predictor as my experience is they can fail intermittently.

Then maybe swapping my computers into somebody's known operational car to check them.

After that, I'd start tracing wires via the written test plan in the CD set.

Just the things that would get tried if it was sitting in the driveway, before shifting into serious exorcism mode.

Leon Speed

I would do these two. Charge the battery completely, it looks pretty low. Check the ground strap for oxidation or better yet replace it. Even if a ground strap looks ok, it still might be a goner, especially if it is the original one.

Then push the gas pedal all the way down and start the car.

Randy V

Much better to continue the original thread than to start new ones, grasshopper.

rgs944

Yep, I think the OP should repost any new info in the other thread. ,