zorbas23x

Hi everyone.Yesterday i was driving my 90S4 around town when all of a sudden the high temp warning lit up on the display in the pod and the gauge started to fluctuate up and down,so terrified i stop at my mechanics shop to take a look at it. I stopped turn the car off as soon as i could popped the hood and called him over.He looked at it felt the hoses and told me it wasen`t overheating.He went and got his laser thermometer and told me to start the car.He aimed the thermometer at the engine for a couple of minutes and told me that the car was fine and that the gauge was more than likely faulty.So i left his place to continue what i was doing and the rest of the morning was fine.In the afternoon around 3.30 i took off again and before i did a miles distance my instruments started to act crazy,my radio was turning of and on and then the car was turning off and on so i stopped right away on the side of the road and turned it off.And thats when i saw the smoke comming out of the engine under the hood.Jumped out open the hood and freaked out The whole wiring harness was on fire so take the key open the hatch took off the tool cover then the spare wheel cover the spare and finally after what seem to be forever took the cable off the battery and smoke no more.called a tow and while waiting for it to come i took a better look.What i saw was unf####beleivable.The harness was touching the pulley and the pulley ate through the wires and they were touching one another and they shorted out and my car almost caught on fire.Very very scarry moment.So warning to every one PLEASE check that part of your car it`s very tight there and even more on the S4`s you never know

Giovanni

So sorry to hear that. Why is it that each time I drive a shark I am afraid it may catch on fire? D you guys feel the same way?

Do you have pics of the damage?

zorbas23x

I will later on.I am out the door now to see my mechanic and the car.And i forgot to say tha it was the air pump pulley that did the damage to the wiring harness

heinrich

VERY COMMON.

Someone does the tbelt job and leaves the main engine harness loose or too near the ac belt/pulley. It will wear through and cause this. I am sorry you had this happen, it will be a hell of a job and expensive to replace that harness.

Bill Ball

The front harness should be fastened to a bracket that also holds the spark plug wire looms as they cross over the front of the motor.

dr bob

What Bill said.

More than a few cars are running around with that harness just flapping there, unsupported. I've also seen some where the clamp that screws to the lift bracket is also left loose. Obviously very dangerous!

borland

It could also be the power steering belt pully that shorted out the thick ABS cable (+12V). As this cable routes from the timing belt cover, over to the junction in from of the power steering reservoir.

This ABS cable also needs to be moved during the TB/WP maintenance and is easy to improperly reroute.

Bill Ball

The cable borland mentions has a tiny plastic clip that goes into a hole on the TB cover and helps a little bit to keep the cable away from things. The clip is often broken or missing. And as borland said, routing is the more important issue. That cable should go back behind the power steering reservoir bracket. On the last WP/TB we did, the Phillips head screw that fastens the end of that cable to the junction block was seized. We had to drill it out. No problem. After we finished we noticed that whoever did the last TB had cut that cable and respliced it.

Alan

Not sure if fires are more common on 928's than other cars - or that we just pay a lot of attention to our babies...

Anyway a battery cutoff switch is a handy thing to have... saves time...

An extinguisher should be to hand of course.

Best of all install a Halon extinguisher system with a direct engine bay deployment system... some peace of mind to be had there.

Better yet install an engine bay fire detection system - since its quite hard to know you are on fire initially... I still have to do this last part.

Alan

MGW-Fla

sorry to hear, know that was scarey. good thing is, your mechanic wil make it better than new.

ew928

I wore out my last set of hood shocks in about 2 years from poking my head into the engine bay and looking around so much.
In my 88, there's a ground cable connection under the tool tray. Just under the rear wiper motor. Much faster to disconnect than trying to dig the battery connections out.

Hope you get the wiring harness fixed soon, George.

Got my flexible fuel lines replaced early this summer after hearing of all the 928
flambe stories.

Ernest (NYC)
I'm a gnoid. You're a gnoid. We're a Pair-A-Gnoid

cambria

Alan---I enjoyed meeting you in Denver, and you trip to and back sounded great. I have a couple of questions, can you expound on your disconnect switch at the battery and also your detection system. I know the 88 S4 had a cat detection system, is this adaptable to the 87?
Thanks, Terry

Tony

I snagged a battery quick disconnect from Mark A last year at Sharktoberfest. Handy little thing to have when you have to "kill" the car in a hurry.

Alan

Terrence,
My disconnect switch goes where the battery ground strap attaches to the frame at the ground point. Where the wingbolt is on earlier cars but its just a bolt on the GTS.

Tony - this is great for working on the car and for cutting all power if needed (as in the above case). Its not good for killing a running car since it only takes the battery out of the circuit - the alternator will probably still run the car - but with lousy voltage regulation which could fry some of the electronics and/or damage the alternator itself... Fortunately we have the easier access ignition switch for this ...

Terrence - I do not yet have a fire detection system. I was thinking of hijacking the unused Cat Fire indicator in the dash however it would need a new logo and drive circuit - the easiest solution is a fast acting thermal switch located around the middle of the hood. Not sure what value is needed but I'd assume probably about 250 degrees F. Probably need to experiment.

What I do have is the cut-off switch and a cabin mounted hand held Halon extinguisher and SS braided plumbing from the passenger compartment to the engine with a quick connect in the drivers footwell (matches the extinguisher nozzle) and 2 nozzles/jets firing forward from the bulkhead along the cam covers (and therefore fuel rails).

Thus I have a handheld extinguisher with a flex nozzle (good for fuse/relay panel and general portable use) as well as a means to get halon quickly into the engine compartment without even opening the hood (actually without even leaving the drivers seat). So what I still lack is the means to be certain its on fire without opening the hood...

See: https://rennlist.com/forums/showthre...eferrerid=6055 Towards the end for more details and photos.

Also: https://rennlist.com/forums/showthre...eferrerid=6055 and

Alan

F4GIB

Can we get a photo of "proper" installation?