Bertrand Daoust

Hi everybody,

I tried to start de car after my intake and valves covers R/R but it does't start.
It cranks fine but does't even try to start.

I checked in the fuel rail but no fuel there???
I will check later this afternoon if there is some spark at the plug and if the injectors are clicking.

In my intake R/R, I changed:
Crank position sensor
Hall sensor
Throtle position switch
Knock sensors (2)
All the gaskets and seals

The car was running fine before that.
Had all the spark plugs, spark plug wires, distributors, caps, coils changed last year.

Any advice will be very welcome.
Thank you.

Bertrand Daoust

Ok,

I checked and there is sparks at the plug (checked 1),
I can hear the injectors (checked 2) clicking
and I can ear the fuel pump running when turn the key.

It looks like the fuel can not get to the fuel rails.
What can cause this beside obstuction (witch I doubt)?

Thank you.

Bill Ball

Bertrand:

The fuel pump does not run when you turn the key unless the starter is cranking or the engine is running, and I doubt you could hear it then. If you have no fuel in the rails, the likely problem is the fuel pump fuse or relay. In your model year, these are common "53" relays and you have some ones you can try to swap in, say, from the horn or blower. Normally on a no-start that is not a fuse, I temporarily bypass the fuel pump, LH and EZK relays by removing the relays and putting jumper wires in the relay panel sockets, bridging "30" (battery power) to "87" (relay output). The fuel pump will run, or should, all the time you have the fuel pump relay jumped. If the car starts, I then go through a process of elimination on the relays. Anyway, in your case you say you have spark and hear the injectors clicking (I'm going to get back to that), but have no fuel in the rails, so you could just focus on the fuel pump relay and fuse.

If the injectors click rapidly when you turn on the ignition - they should not click unless the starter is turning or the car is running - that is one of the common signs of LH brain failure.

Another possible issue that could have been caused by the work you did is a short in the fuel injector harness. You had to remove the rails to take the manifiold off, and in that process you usually pull off the fuel injector plugs or at least they get heavily manipulated. When these plugs and wire leads get old and brittle, they are subject to electrical shorting often hidden under the boots. A single short in any injector harness plug will prevent all the injectors from firing as they share a common ground. However, you report that you believe the injectors are firing. If so, that would rule out this potential problem.

DANdeMAN

Welcome to the club Bertrand......

Bonne chance.....

Bertrand Daoust

First, thank you Bill for the response.

Ok. When I turn the key (witout cranking), I ear someting from the back (I think!)
underneat the car and I tought it was the fuel pump. Sorry about that.

When I mentioned that I hear the injectors clicking,
it is when cranking and not only when the key was in the acc. position. So I think it's not the LH.

Like you suggest, I will swap the relay with another one and try that.
Also you mention a fuse, is there a relay and a fuse for the fuel pump?

Thanks again.

Bertrand Daoust

Thank you!! I guest it's part of the game.

Mrmerlin

get a fuse relay chart here www.928gt.com find page 2 and then tips and links, print one off for your car

mark kibort

are you sure the fuel rails are clicking?

are you getting spark? check this. (edit; sounds like you see a big spark on the plugs or cap?)

If you have fuel and spark, it should start, unless you damaged the crank sensor on installation, or there is a bad connection. just trying to think of the simple stuff.

do you have enough battery voltage? check this. a low battery, even though it turns over, will not start the car like the older buggers will.

jumpering the fuel pump relay is the most telling test. when you jumper it, the fuel pump runs or not. If it runs, and it doesnt when you turn the key, something is up with the computer or connections.

mk

Bertrand Daoust

Mark,

1) I hear the injectors clicking when cranking (with the help of a screwdriver on my ear).
2) Yes I got spark (remove one spark plug)
3) The battery is fully charged (was turning very easily)

I will try to change the relay with another one - if I can get them out!!!
F... there tight there. Is the a tool or something to remove those?

Thank you.

Mike B

Bertrand, I know what you mean...those suckers are hard to get a hold of. I believe there is a specific toll designed for pulling the relays but I never acquired it. The Porsche Gods may strike me down but I gravitate to a set of long nose needle nose pliers and gently wiggle the relay out...So far, so good.

Bertrand Daoust

...And it's right behind the LH and EZK. Not mutch space there.

Bertrand Daoust

Ok. I have removed the relay and change it with another one and did the same with the fuse with no luck!
Tomorrow I'll try to bypass the fuel pump and see then.

Thank you to all.

Mike B

Bertrand...are you sure you are getting fuel to the injectors? I ask as I had similar symptoms and found it to be a plastic cap between the rail and the feed line. Mine was a replacement engine and I obviously missed the cap when reassembling. Perhaps your pump is dead? Just a thought...

Bertrand Daoust

I forgot, I also changed the fuel pressure reg. and the front fuel pressure damp. The rear fuel pressure damp. is 3 years old.

Mike: No I don't have fuel in the front section of the fuel rail. I removed the nut at the left of the rubber hose between the right fuel rail and the front fuel pressure damp. and it's bone dry there! Now, I did the same thing with the nut under the fuel pressure reg., the one at the end of the metal and rubber section (this one is new too) between the fuel cooler and the FPR and there was fuel there. As this section was dry because it was new, I guest that the pump is working. Is there something wrong with the FPR?

Mrmerlin

probably a good chance there are plugs that you have missed in your new dampers and FPR, time to open things up and do a visual.
Get a small hose and blow through the line see if there are restrictions, this could be something simple