tuk_928

Well gang, I had an interesting trip home to Gainesville from the Tampa / Clearwater area after a nice weekend of tooling around in the S4. My car performed flawlessly (e.g., got 20 mpg) except for the previously noted Hall Sender issue that remains to be chased down and repaired...sure miss the extra umph from the 6 degree timing retardation. Seems to be a rash of these problems in the school of late, eh?

After a final high-speed run before arriving home through the pulpwood forests on SR 21 through such metropoli as Otter Creek, Bronson and Archer. I experienced a sudden loss of power...sort of a bogging down really...that I've experienced in other cars (BMWs) when unmetered air is entering the system through a loose or cracked rubber boot.

I coasted off the road after the engine stalled out...proceeded to be eaten alive by giant FL mosquitos...and then began running through the various scenarios. I didn't panic because there was NO indication of a timing belt or cooling failure or otherwise...no odd noises, no smoke or drama at all.
Called AAA to get on their tow truck waiting list. Called my fellow 928 buddy John Johnston ('89 s4 a/t - platinum on black) in the Athens GA area and ran through the possibilities. We decided that it probably was something electrical most likely a failing battery or charging system (alternator) or a loose wire.

EUREKA!!! Turned out that within 10 mins I located the source of the problem after first checking the battery connections and ground strap condition --- I saw that the COIL WIRE for the p/s cylinder bank (where the hall sender is located) had worked its way off and was laying precariously at the opening to the coil receptacle. The damned coil wire was covered with corrosion presumably from all of the humidity and ARCING that had been taking place. Who knows how long this could have been going on...may have been like that at SITM.

I cleaned the connector with what tools I had and by that time the tow truck guy arrived. Let me tell ya folks...if you haven't found out for yourself already...that damned wire is very short and the access to the coil is quite limited. I burned the shiite out of my fingers on the radiator and radiator hose and tranny cooling lines when trying to get the wire outta there to clean up the plug If I ever meet the person responsible for choosing that mounting location for the coil...may have to kick his ****

The tow truck driver had a Leatherman tool (and long skinny fingers) that he used to work the cleaned-up connector back onto the coil...took 5 mins....what a pain. The car fired right up once everything was back in place and I drove it home with no problems at all. Tow truck guy followed me to the entry of my subdivision and we waived goodbye...what a relief that I didn't have to have my car hoisted onto a flat bed...always make me anxious.

Anyway, all's well that ends well....the coil wire will need to be replaced because the little copper fingers that help hold the wire in place broke off during cleaning Also, the coil receptacle needs to be cleaned due to the corrosion. SUGGESTIONS APPRECIATED here, please...baking soda and a toothbrush?

Sorry this is so long...just wanted to share my first experience of being temporarily sidelined in my Shark.

Best,
Tim


ps.
Anyone have an extra coil wire they can sell me cheap? I can trade you a 928 dipstick?

Randy V

Didja tip the tow guy? Sounds like he went above and beyond the call.

dr bob

Skip the baking soda and use a fine wire brush to clean off the crud down to bare metal.

High-voltage connections are usually treated with silicone hi-dielectric grease to prevent contamination and future corrosion from same. Make sure you have a very solid mechanical connection available, then coat the metal bits with this grease and assemble. This grease is sold as "spark plug grease" at better parts stores. Comes in little plastic one-time-use squeeze tubes for less than a buck. I have a giant tube of the stuff, labeled as Dow-Corning #5, used to protect high voltage bushings from flashover in power plants. Same stuff as in the little tube I'm sure.


Good test of your four-cylinder mode while driving, and kudos to you for finding/fixing the problem before you were eaten alive. A herd of florida 'skeeters sounds almost like a 928 with RMB. Hint-- they were following the car...


Cheers!

Shane

That's funny, Bob, I have a big tube of that stuff too.

tuk_928

Randy,

Absolutely...gave the tow truck guy a $NICE tip$...he was most appreciative. He also did me a favor by cancelling the call into AAA to save me one of my maximum of FOUR alotted service calls per calendar year. Nice of him to do that.

I wasn't aware AAA had rationed the service calls...I'm a PLUS member too!

Bob,
Nice of my Shark not to let me down in a rough spot...had a nice damp, shady (big live oak trees), mosquito infested spot to test my deep wood off (w/40% DEET - ain't this stuff a carcinogen?). Thanks for the kudos...it felt good to rescue myself from the side of the road and to send the tow guy packin'.

I have the wire brushes in question to clean up the connector...will do that and coat with the goop mentioned. The other coil doesn't have the goop in place...should I treat it too? Also, the little retaining splines on the coil wire disentegrated when I field dressed it with...God help me...a napkin and the el cheapo screwdriver in the Porsche toolkit

What about getting at the receptacle in the coil? That'll be a PITA to do. Maybe a pipecleaner or a metal version of the same thing?

Best regards,
Tim

Randy V

If you happen to have a Dremel tool, the small brass wire wheel works excellent for cleaning corrosion from connections without damaging them.

Jim R.

Tim,

I recently removed and cleaned all coil connections. The passenger side may be easier to just remove. I think I used a 10 mm 1/4" drive and extension, pushed the cooling hoses over a little, and just removed the whole assembly. Very easy to clean with coil in hand. Should make the job easier, plus you get to check the power and ground connections as well. Took less than a half hour to R&R each side.

Good luck

Jim R.

wds928

Tim:

The "limp home" mode of the computer really scared the crap out of me a couple of weeks ago. Also turned out to be a poorly connected coil wire.

Glad you got it fixed.

tuk_928

Randy and Jim,
Great suggestions!...Thanks. Randy, I have been looking for a reason to buy a Dremel tool. I agree with Jim that it may just be easier to remove the p/s coil as a unit and clean it thoroughly. When I was futzing with the coil wire noticed that my hands got all grimey with tranny fluid....I'm presuming. I believe there's some some small seepage from my tranny coolant lines attached to the Devek radiator...perhaps I can snug those up while I'm in there. Susan Thomas' told me to check for the presence of (three?) copper washers. Will do...

Bill,
I remember seeing that "limp home mode" thread but didn't read it...was that your post? I've never had the coil wire ease its way out on any other car I've owned...maybe I should duct tape it on there? Or is that mod a big ? I'm kidding...of course I wouldn't do that. I'm not sure if my car made it into limp home mode...it began running like a herd of turtles for a block or so and then stalled out...and I coasted to a safe place off the main road.

Best,
Tim

wds928

Tim:

I think that was my post on the "limp home mode". I had just changed my distributor rotors and caps. The car started fine and ran fine. The next morning, drove into town for breakfast and while on the Interstate, the power fell off the table, no warning lights, just an awful $$ound.

A post on the board and a couple of responses led me to the probable culprit. I removed completely the passenger side coil wire and re-attached it. It's run great ever since.