Any other replys folks??? I need to attack this armed with as much info as possible. TIA,

 

Chris, I don't have anything else ta send ya right now. But, if you want you can give me a call and I can give you a blow-by-blow description of how to R&R the sensor. PM me and I'll shoot you a phone number and we can work out a time...

 

I decided to check my hall snesor while I had my cam covers off for powder coating. Guess what I found. It was definately frayed and probably not working. By the time I got it off two of the wires were broken. If they weren't broken before then they were just hanging on by the skin of their teeth. Hopefull this means I'll gain another 20-30hp as that is about what you lose with 6 degrees retard at 500hp. I guess we'll see soon.

Another method of geting to the 2 allen bolts that hold the sensor in place may be to jack up the engine instead of removing the cam cover. I don't know if that will work or not but could save some time if it does.
HTH,
Andy K

 

Umm... that inboard-lower bolt is occluded by the edge of the cam cover. Also, access to the outboard bolt is difficult due to the engine lift loop - which I had to bend out of the way to get the cover off. Is any of that going to change if the engine is lifted a bit?

Where's your p-side engine lift loop anyway?

BTW, it really would be nice if someone found a way to get to that thing without R&Ring the cam cover...

 

The inboard bolt is not occluded by the cam cover on my car.

Jacking the engine slightly will allow more room to get one's arm in between the manifold and shock tower to remove the single 13mm bolt that secures the engine hook. Remove the engine hook and with the engine higher it should be easier to get at the bottom or inboard bolt as there will be a little more room between the shock tower and the engine.
HTH,
Andy K

 

Ahh! But, of course! Yes. That might, indeed, help.

I suppose you'd raise the engine slightly, support it from underneath, and then go to town.

 

I'll take a better picture of one of the GT's for comparison.

Is you cam cover already off in that picture?

 

Dave C (worf928),
Thank you for your posts and your offer to help me out with this problem as well. I apologize for not getting back to you sooner. Not much time on my end for car fun lately...IF you consider repairing the hall sensor "fun"...maybe if my hands were smaller

Question re: the effects of the 6 degree timing retard from the non- or mal-functioning hall sensor. Will this tend to make the engine run hotter? The reason I ask is that a fellow PCar enthusiast here in town suggested that it might...but I forgot to ask him WHY...

Thanks for the photos GoRideSno....particularly of the exploded view of the hall sensor bits and pieces.

Best,
Tim

 

I would not think that it would. It didn't in my case.

 

AndyK and Dave C,

Is it possible to REPAIR (i.e., resolder) the frayed wires on the existing hall sensor rather than installing a new one? At this point, all I have done is been able to confirm that the thing is indeed plugged-in. Beyond that, I haven't been able to dig into the problem further...looks like it can end up being a real PITA.

Good luck with your repair Chris!!!

Best,
Tim

 

Tim

Yes this is what I did to repair mine, actually the connector had broken, so I used the connector of an old knock sensor I had hanging around.

Chris

 

You can certainly repair the wires. Make sure to also repair the insulation. If that is the only thing wrong with the sensor then I suppose that it is possible to fix.

However, the wires on the sensor on my '89 were not frayed at all. The thing was still toast.

Last spring the speed/reference mark sensor on my '91 toasted with no visible damage to the surface or wiring.

It's a question of your time versus your $$. The Hall sensor is not cheap >$100 if I recall correctly. Weigh that cost versus the time to R&R it twice if bad wires are not the problem.

Good luck widit!

 

I just went out to see if I could get a picture of the sensor's cover with the cam cover on. No dice. Too much stuff to move and too little motivation to move it for a picture. The front main harness needs to move, gotta get the airpump hose out of the way, lift loop, *FLASHBACK*! Blech.

What's really fun is that you have to get all of that stuff out of the way just to figure out how much of the PITA the job is.

Someone's just going to have to take a shot and see if Andy's idea of lifting the engine up allows easier (less time consuming) R&R and report back to us.

Anyone who can document an easier way (than removing the cam cover) to get the Hall sensor out should get a Rennlist award or free beverages of choice at the next 928 event!

 

Thanks for the pics Andy. That helps. Unfortunately I've been very busy with Doc visits for both myself and Christine, plus lots of other fun stuff (NOT!!!!!), so I haven't had time to dig in and do it.

Hopefully in the next few weeks I can get around to replacing the sensor, as well as R&R'ing my RR wheel bearing. Those are the only 2 immediate maintenance items on the agenda. I will try Andy's idea of jacking the engine, and report back on my results.

 

Hey guys, just wanted to express my thanks to the posters of this thread. With the help of John Speake's Spanner (great device, John!) that gave me an intermittent Hall Sensor code and the pictures and descriptions in this thread I was able to trace the hall sensor wiring from the sensor around the front of the engine. Sure enough, the wire must have occassionally been rubbing against one of the belts because the insulation was slightly worn through in spots, exposing the copper wiring. This exposed copper must have been occassionally grounding to something metal in the vicinity to give me the Hall Sensor fault. With a little electrical tape, a zip tie to hold it in a safe location and a battery disconnect to clear the codes . . . BAM! - No more retarded timing and power was restored. I hadn't really noticed what I was missing until it came back. Man, when these cars are operating correctly, they are a blast!

Thanks again to you guys and Rennlist!!!