Fontana

When you turn the key to the On position, should there be any clicking sounds coming from the CE panel? When I turn the key to the On position, I hear about three slow clicks coming from the CE and that's it, the sound does not continue. When I put the key to the off position, I will get the same number of clicks. I felt the relays and it appears that the first relay on the top row and the last relay on the top row both are clicking together at the same time. Is this suppose to happen? I replaced both of them and it still does it. (1987 Porsche 928 S4 Automatic)

I also do not hear the fuel pump turning on when I crank the car. I know it works as I have bypassed it and it will go on, but...

Any help would be greatly appreciated as I am trying to work out all of the bugs here...I finally got under the car yesterday and re-established the main ground by sanding the contacts and most of the grounds on the car. I had it running (very rough) the day before yesterday, but now it cranks much better (noticeably better after cleaning the ground contacts) but will not start for nothing now. I am thinking maybe I flooded the motor and have to pull the plugs again (for the third time). When the car was running, it appeared to be running very rich with a lumpy idle from 200 rpm to 1000 then would die out with some black smoke coming from the exhaust and started to clear up as the car continued to run. The battery is weak, so I keep my work van running with jumpers to the Porsche as I try to crank the car if that is worth anything...

I noticed the left side cat getting red so I am not sure if the car was just running hot or if I have a blocked up cat. The car did not want to rev beyond 2000 rpm. I tried pulling the connector off the Mass Air, it did nothing. I tried pulling off the Temp II connector, it did nothing to help get the car started as well as joining the Temp II connectors. I also tried spraying WD40 inside the valve under the intake, but I cant get the car to start now, so I don't know if these remedies will help the rough idling since the car wont start.

I was up till 3 am reading all of the related posts here. Frustrating as many don't finish their posts so you are left hanging. Checked all of the fuses, pulled the 14 pin connector in the engine bay and cleaned it's contacts, pulled the connectors off both computers and cleaned the contacts. Car still won't start. Lot's of bugs...

Anthony

dr bob

The symptoms you describe sound a lot like a failed LH controller. If yours is the original, it might be worthwhile getting yours into a good running car and see if the symptoms go with the controller.

The single red-hot cat might be an indication of failing ignition if the LH isn't the culprit, but each ignition feeds both sides so it's not definitive by any means.

There's a possibility that cam timing has jumped on one side, but it's unlikely that it would be the left side (driver's side on US cars) because of the belt routing. The passenger side is more likely to slip in my estimation.

My nickel goes to the LH controller failing.

SteveG

If this was mine I would get the batt load tested, and charge replace accordingly. I would check the ground strap (ohm). Did you check the grounds to coils, coil and distr connections? I would try to isolate fuel, spark, timing and determine which is the issue. Sounds like you have fuel, but you should hear the pump momentarily before cranking (but could be insufficient pressure). From the driver's seat, I don't think you can hear it when cranking. What is the tac doing when cranking?

In your post, it would help to id the relays by name and number. I looked up the first and last relays at 928gt.com and both are "not used" on an 87. Sounds like the relays have been tampered with. Try removing those relays. There is some issue around the kickdown relay; make sure there is one. I seem to remember it won't start w/o it??

Running rich could be vacuum related (unmetered air).

Fontana

Thanks for the quick response guys. The relays that are clicking are #2 & #12
Also, I found it odd that #21 is a "Ford" relay?

I bought the car this past Mothers Day and when I got it running (poorly), the car always made that same clicking sound even when running. I was told that if the LH Controller was failing the car would not run at all. Is this accurate?
I sanded all the grounds that I could get to and used Dielectric grease. The ones that I have not gotten to as of yet are the two on the bellhousing, the two on the inner fenders for the coils (I believe), the one under the drivers side floor and the one under the washer canister (drivers side engine bay). I checked for spark and I have spark on both sides.
The tach jumps a bit while cranking, more so before I sanded the main ground contact. It use to jump up to 3000 rpm, now that the main ground has been sanded, it jumps up to 1000 and I have noticeably better cranking power so that was a needed fix.

Fontana

I just went out and pulled the above mentioned #2 and #12 out and the clicking stopped. I put them back in and pulled many of the others out and checked/cleaned the contacts and for the first time (along with the friggin clicking), I now hear the fuel pump prime when the key is in the On position and again when I turn the key to the off position. I never got that before and I was listening for it. Progress?

Now the battery died as I tried to start the car on it's own without the help of jumping it off of my workvan. I will see what I can do tomorrow. I did try to start the car a few times before the battery died with no luck, but maybe I didn't give the fuel enough time to pressurize?

Fontana

Also, #8 relay is clicking (the relay which has the green light and can check the fuses).

Bill Ball

No. The fuel pump does not prime in S4s.

It pressurizes in a second or two unless the fuel rails have been off.

Bill Ball

2, 12, 8...

Where are you getting these relay numbers?

I and II are a single relay. There is no II (2?)
XII (12?) is the horn relay.
VIII (8?) is the defroster.

None of these have anything to do with starting the car.

Wait, I think I deduced your code. I ran it through my Flash Gordon decoder ring and it told me you are counting the relays from the top left. So, 2 = IV, 8 = XVI, and 12 = XXV. That's better. So, the relays that are or were clicking are ignition, EZK (ignition brain), and LH (fuel injection brain). I'm not sure why, but inadequate voltage could be the underlying issue.

Bill Ball

Dr. Bob is always right. Still those relays clicking don't mean the LH has failed to me.

You indicate there was no change when you unplugged the MAF. That would indicate the MAF is in limp mode. In this mode, the car will start and run but barely and the throttle response is quite odd. It defaults to just a couple of injection pulse widths rather than measuring load and using the fuel maps.

But before you start blaming the LH brain or other parts, you need a good battery. Some may say that doesn't sound likely because it ran badly when jumped and once it ran it should have alternator charging, but it may not be true.

outbackgeorgia

Battery, battery, battery

dr bob

Spread the word...


Clean the battery connections, including the smaller wires on the battery positive clamp. Charge the battery. If it won't hold a charge, replace with new. Fuel pump, fuel injection, fans , run directly from the battery through those smaller wires, some through relays.

A failing LH can show differing symptoms. Some have clicking injectors and run way rich, don't respond to MAF changes or temp-II changes. LH also runs the fuel pump, but only when it receives rank position sensor pulses via the EZK (ignition) controller. So the relay noise, MAF insensitivity, runs when cold but won't rev under load, etc, all point to LH crash.

Bill Ball

Yep, like I said, Dr. Bob is right even if it didn't seem right to me. The LH has many failure modes and this sure could be one of them. Anyway, we all suggest the battery needs to be attended to first.

Alan

Get the battery checked - pretty sure you will find that a new one fixes this.

See where the dash voltmeter ends up with the key in starter posistion...

Once you have a new battery - make sure the alternator is charging OK?

Alan

Fontana

Bill, I got the numbers off a relay chart from 928 International which is numbered 1-24.

Fontana

[QUOTE=Bill Ball;9631335]No. The fuel pump does not prime in S4s.QUOTE]

So what is that sound that I am hearing then? I honestly did not go in the back of the car to see if it is actually the fuel pump priming that I hear, but it certainly sounds like it from the drivers seat. I will have my fiancee turn the key after breakfast while I listen out back for the sound I am hearing. What else could it be? It's a brief, audible, humming sound, when I key on and when I key off.