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Posted by: Carl Oct 25 2003, 02:19 AM

My son called from college last week and said "Hey Dad, let's go to the Saint Mary's/Cal Poly football game this weekend!" I'm always up for a good road trip and football game. Since both schools are less than stellar on the field, one out of two ain't bad.

On Saturday, the sports we are, we tossed the ovenight bags in the 911 and jet off on the 3 1/2 hour trip to San Luis Obispo. It's a fun trip, we talk and play loud music. Half way there we swap seats and he drives.

In San Luis and have a couple of hours before the game so I show him where I went to school in the 70's. In the middle of my nostalgia trip he's feeling uneasy about driving a clutch in traffic. He pulls over, we swap seats again and I turn the key to fire up the trusty 911. Crank, crank, crank, pffffft. Crank, crank, crank, pffffft. Crank, crank, crank, pffffft. Damn.

Hmmm, wait a couple of minutes and try again. Crank, crank, crank, nothing. I can't believe this. Lots of cranking, lots more not starting. There's a gassy smell so I pulled a spark plug. It's clean and dry and shows a good blue spark when the engine cranks. That's not the problem. Remove the gas line at the filter, lots of gas and pressure. Reassemble. Try it again, the engine fires, coughs, runs really rough and dies again. No joy.

I call a friend in San Jose and he's no help. Take it to a dealer, he says. Right. There's no Porsche dealer in SLO, it's late Saturday afternoon and I've got a few tools, no shop manual and no idea where to find a competent mechanic. It's getting dark and so's my mood.

After a while with no success we leave the car there on the street and go to the game with a friend. St. Mary's, true to form, is down 28-0 half way into the second quarter. This was the only part of the trip that's going as expected.

The next morning the engine starts, runs for 2 minutes, gets ragged and quits. It won't start after that. The guy who lives in the house where the car is parked is very friendly and well-meaning. "Y'know, I've got a buddy who works on Beemers, he can take a look at it." I don't think so.

Sunday, my son makes the trip back to San Jose on the bus, I stayed in town and on Monday morning had the car towed to a local shop. They had it fixed in 2 hours and I made it home by 3:30 that afternoon.

Lessons learned:
Cylinder head temperature sensors do really strange things to the DME computer when they fail. If the car starts you can fool the computer by using a 200 Ohm resistor to ground on the sensor wire.
Replace the old style, one-wire sensor with the two-wire type.
Guy's Independent Porsche Repair is a very good shop. They were very responsive, diagnosed and fixed the car quickly and for a modest cost.
Be prepared for stuff to go wrong after a long drive on a hot day. Heat-soaked engines will do that.
Saint Mary's lost 54-10.
Taking a road trip with my son is a good thing and I'd do it again in a hearbeat.

Carl

Posted by: DNHunt Oct 25 2003, 06:15 AM

Bad CHT screws up D-jet too. Doesn't mess with Megasquirt

Dave

Posted by: dgw Oct 25 2003, 10:36 PM

>>Cylinder head temperature sensors do really strange things to the DME computer when they fail.


Was this an 87?

Mine failed 3 times before I sold it. Dealers would never admit there was a problem. It sure was annoying to be stranded in the middle of Nevada on Hiway 50!

Posted by: markb Oct 25 2003, 11:04 PM

Ahhh man, John Larson was just down the road from you in Santa Maria. I'm just south of SLO in Arroyo Grande. We could have had it towed and fixed in the time it took you to watch the game. The upside is Guys is a good shop. Next time anybody is coming into the area, lemme know, I'll be happy to help. Mark

Posted by: Carl Oct 25 2003, 11:30 PM

Dennis,
No, but close. It's an '89 and it's the last year for the SC/Carrera series. These cars have a reputation for being very solid and reliable but it's not a good sign if you had that much trouble.

Hi Mark,
Actually, I tried calling John a couple of times to get his recommendation and got no response. I guess he must have been out of town.

Carl

Posted by: krk Oct 26 2003, 09:08 AM

Carl,

Sorry to hear of the misfortune -- it's sure annoying when a car breaks down on the road -- but it's good to hear you got it back home ok.

Perhaps something with carbs next time?

kim.

Posted by: fiid Oct 26 2003, 01:12 PM

I wonder if we should put together a volutary phone/location list so that when we are tooling around the countryside we can help each other out in case of problem.

Just a thought,

Fiid.

Posted by: redshift Oct 26 2003, 01:45 PM

"This is OnStar, how can we help you today?"

"Yes, my 911 won't start."

"Hmmm, I'm sorry, do you have your customer number handy?"

"Yeah, it's 326 978 1121H.."

"Have you checked your cylinder head temp sensor?"

"No, no I haven't"

"Do you know if it's using the single wire, or a dual wire setup?"

"No, I think it may have the single wire though."

"Well, that can be a problem, without that signal, the DME can do funny things."

"It's Saturday, I don't have any tools, and I don't think there is a dealership around here."

"Don't be a wuss. You can check the CHT wire by turning over the car, while biting the wire."

"Huh?"

"Yeah, don't be a pillow biter, hike up your skirt, and bite the friggen wire while someone cranks the car."

"Ok, I am biting the wire."

RrrrRRRrRRRrRRRrr

"Taste any resistance?"

(muffled)

"Mmmmhmmm"

"How much."

"Hmmm... bouw sebendy fie *slurpie noise* owr atey"

"You need to change your CHT, and go with the 2 wire setup."

(spitting)

"Thanks OnStar!"

"Glad we could be of help."

Posted by: need4speed Oct 26 2003, 03:05 PM

Too bad Franz closed up Performance Automotive (on Monterey street).

Where's Guy's?
(and markb, where's John Larson's? is he on Betteravia).

Posted by: Carl Oct 26 2003, 04:57 PM

Pretty funny. Onstar couldn't tell me anything I didn't already know -> nothing happening until Monday. There's a lot worse places to get stranded than San Luis, though. It's still a fun little town.

That sensor's really buried so changing it without putting the car on a lift is tough. And that's if your lips are calibrated to read the resistance so that you know it failed.

Carbs would've been a lot easier. They may be dumb but at least you can do something with them on the side of the road.

Guy's is on Capitolio Way that's out Broad Street beyond Orcutt.

I'm glad this didn't happen in Barstow.

C

Posted by: krk Oct 26 2003, 05:00 PM

Heck, I'm just glad you get to try this out in front of me!

Hm. There are other road trips I'm considering -- to you take requests? I'm thinking you & son take road trip, find good mechanics and report back.

kidding of course!

kim.

Posted by: Carl Oct 26 2003, 05:16 PM

Many members of this list play down the value of PCA but it was on the local region site that I found the sponsors: Guy's in San Luis and West Coast Garage (John Larson's shop) in Santa Maria. Since there was no response from John, Guy's was my next best guess.

Without the the web site I'd just be picking one of the yellow page ads.

So, Kim, next time I've got a road trip can I take the turbo?



C

Posted by: krk Oct 26 2003, 05:28 PM

Yep.

(well, it won't be back at the house for a month or so -- but if you can stand the wait....)

kim.

Posted by: dgw Oct 26 2003, 11:33 PM

Well................
I actually had two 87's, head temp sender went out on both. Two friends with 87's, same thing. The one that went 3 times had 52,000 miles on it, the other ones around 25,000.

It didn't put me off 911's, I got an SC and an RS America instead.


And yes, I do have a 914, its in members pics somewhere.