Non starting 928 1979 euro

[robucop]

Hi Guy's,

(pardon me for any spelling errors, I'm dutch)

Sorry my first post is a question.

Anyway, I'm hoping someone recognizes below issues and can point me in the right direction.

I bought a 928 1979 euro in January (perfect interior, OK exterior) and it was running great for a couple of weeks. However, since i needed new shocks on all corners, i toOK a loOK and figured it wasn't something i wanted to do myself so i brought it to a local garage.

It seems that was a big mistake....

When i picked the car up again at the garage after 3 days (it was dark and poring with rain, the car would hardly start and when it finally started it ran very bad, it would build up revs very slowly and no more than 4000 rpm. I toOK a loOK under the hood and saw one vacuum line to the ignition distributor was brOKen so i figured the bad running was due to bad ignition timing and limped home.....second big mistake.....

As you may already have figured i replaced the vacuum line but that didn't help anything. Now the car won't start at all.

Next step was to start replacing normal maintenance stuff ( fuel-filter, spark plugs, air filter) and see where that would lead, of course that didn't help so i also replaced the ignition coil, distributor cap and rotor arm. I can get a spark at the plugs and the coil.

I checked the relay's and fuses and they seem fine (also, i can hear the fuel-pump running so that seems fine too)

I can smell gas via the exhaust after trying to start and the plugs get get wet so it seems to be getting fuel.

Now I'm lost, what else should i consider checking, temp valve, wur....?

Any feedback would be greatly appreciated.

RoBuCop
The Netherlands

[Maleficio]

No start: begin by verifying ALL of your ground wires and terminals. The shop probably backed out a couple of ground screws to manipulate you into paying them for a bogus fix.

[robucop]

Hi Maleficio,

Thanks for the tip, I'll take a look at the grounds tomorrow.(it's getting to dark outside)

[Maleficio]

I just fixed my no start after five weeks of on and off again troubleshooting: loose injector computer ground (hidden very well). Thanks to Landseer, it all came together for me, now I can move on to fuel delivery refinement.

[Dean_Fuller]

Check the 14 pin connector doesn't have water in it. Also make sure the jump post has its cover installed. Sounds like the heavy rain has gotten into something.

[robucop]

Cool,

Thanks guy's, you're great, it looks like i'm in for some serious troubleshooting tomorrow...

[JK McDonald]

Hey Robucop, Just a word of caution when turning in your Porsche to a repair center. Be sure to write down the odometer reading and make it a point to mention this precautionary step to the manager and at least a couple of the mechanics standing around. There is just something about having unsupervised access to a set of Porsche keys that has a tendency to unmask the latent maniac test drivers amongst the service techs.

A friend had a bad experience when he dropped his 928 off at a local garage one morning for an afternoon tune-up. After a couple of delays, he was finally able to pick his car up late the next day. It was running about the same but his clutch just didn’t feel right and there was a whiff of smoke between gears that wasn’t there before. He also noticed new oil leaks along the cam covers. About a month later he was told that one of the mechanics had bragged about thrashing a black 928 all day long as part of his test run. Naturally the manager denied that anything had happened.

Although there are situations when the call of a 928 sitting quietly in a parking lot can be like the Mythical Greek Sirens who called sailors to their doom, hopefully your no-start issue is just a coincidence of the rain and you will find that something simple has caused the problem....

Good Luck, Michael

[bluemane500]

hey dean, do you have a pic of the jump post cover ?> i never seen one nor do i have on either of my cars thanks

[JhwShark]

Here is mine

[lfausty]

slight hijack

jump posts , cap on a leash -- was typing when bluemane500 entered--- b500 in search box type jump post ( going to be page 4) danglerb 2-08-2008 thread titled Does anyone have a 928 --- --- -- good read for different yr covers..........

[bluemane500]

wow that is oem? never seen one before

[neil30076]

Thats OEM, all my cars have them!

[JhwShark]

The Jump Post cover holds on the Transistor Igniton Unit cover (which covers the 14 pin connector as well); both available at 928 Intl.

[JK McDonald]

Hey Robucop, It sounds like you have checked and/or replaced all the basic parts. If your plugs are wet with fuel and have a good spark - perhaps your cam timing belt has jumped a tooth or two. Your next step should be to pull the plastic cam gear covers off and verify that the cam timing marks line up with the crank. There are a couple of good write-ups on this procedure - just use the upper right “search” function found under the User Name and Password log in. You might try something like “Timing Belt Installation” as your search topic.

Good Luck, Michael

[robucop]

Hi Michael,

I guess you could be right about the garage, it crossed my mind as well.
However it could still be a simple issue and i prefer to focus on solving the problem instead of driving myself mad...

Thanks for the tip about the cam skipping skipping a tooth or two, that makes a lot of sense to me, I'll be sure to check that next.

[Maleficio]

Will a skipped belt cause rough running?

[robucop]

Hi Maleficio,

You've got a point there but i can imagine that if the belt has skipped 1 tooth it would be possible to have rough running and if it skips more teeth it would stop running all together.

This would fit the scenario i experienced.

After reading a lot about the 928 issues on several fora another cause may be the green wire?

[robucop]

oh, right...

I forgot to mention that i found two loose wires in the enginebay coming out of the harnas.
1 blu/red and the other brown, i think they are suposed to be connected to the coolant level or pressure sender ( on top of the expansion tank is a connection post with no wires attached).
The wire however is too short to reach and has different connectors so i think the PO must have had a home made extension on it that is missing now.
I don't think this would cause the car not to start but it does mean they obviously messed about with the wires in the garage bacause they are in plain sight and i never noticed them being loose before.

[JK McDonald]

I have seen a timing belt cause a wide variety of start, power and run problems. The overall negative results will depend on the number of cylinders of an engine, weight of the flywheel, cam profile, torque curve and the horse power.

A single tooth out of synch on only one cam bank will generate a loss of power, rpm run-up and extended/hard start problems. Naturally, if during your inspection you notice missing teeth and both cams are out of time with the crankshaft, you’d have major sputtering no-start issues.

I am not saying absolutely that this is his problem - it is just the next logical step in the troubleshooting process after reading about all the things that have been done to this point.

Good Luck, Michael

[robucop]

Hi Michael,

Thanks for the feedback, at this point all sugestions are welcome.
i'm glad you guy's are taking time to help me on my way.

Very cool!