951rook

Just purchased an 86 951 with 177,000 miles on the chassis, and about 500 miles on the engine and tranny. I'm new to Porsche in general, and need help with some of the problems that have become apparent to me.

1. Speedo and odometer don't work
2. Turbo won't boost past 5psi, I have an in cockpit mbc; how do i return it to a stock configuration?

That should get me started. I don't really know where things are located in the engine bay, I've only dealt with toyota mr2, a completely different and more simple vehicle. Thanks in advance!

badcoupe

Have youy been through all the fuses in the fuse block with a test light? That amy solve your headlight and cluster issue. The boost issue could be a bad wastegate or a problem with the mbc. Check all the lines to and from it closely. The WG's on the cars aren't the best after all these years of use. make sure none of the IC pipes' connectore are leaking. I had the one at the throttle body split on the bottom side where you couldn't see it.

951rook

checked all the fuses. only bad one was #10; fan cooler if i remember right. I have alot of pics of some straggling wires. ill post them up and hopefully get some feedback.

951rook

951rook

discovered the headlight problem. bad contact point within the steering column. my next question is can you test gauge cluster's functionality? I have it pulled from the dash.

951rook

another problem knocked down. cleaned the contact points on the back of the cluster, got the fuel gauge working. now its just the odometer, tachometer, and speedometer.

AScholtes

My suggestion as far as boost.... get rid of the MBC and tie back in the factory components (cycling valve). Do you have any way to tune the car after adjusting boost levels? If not then you are looking at alot more money when you pop something in that motor from too much boost, or from way too much fuel.

Also, check for vacuum leaks...

User 52121

That's capped when you run an MBC. Normal.

A/C Compressor wire.

Alternator cooling duct. There should be a flexible hose connected between that duct there and the shroud on the backside of the alternator.

951rook

Thanks for the replies. As far as the boost and "tuning" I have autothority chips on the way. I also have a lindsey boost enhancer, however, i don't know how to install it. The hardline that it attaches to opposite of the banjo bolt is absent. Is the cycle valve under the intake manifold. I'm not sure how to go back to stock. Another problem arose last night. The check engine oil light is on. I just changed the oil, the light was on prior to that. The oil pressure reads 5 bar. Also how do i rid of the exclamation point at the top of the cluster. Anything helps guys. Thanks

951rook

Also after reading about speed and reference sensors i went and found them, the speed sensor didn't really wiggle side to side, but rather had about a 1/4 in of vertical play. Is this normal?

hevquip

This seems like somewhat of a relevant topic, so is there a way to turn back the odometer? I either want to zero it so the odometer reflects the rebuild and bigger engine, or at least roll back the first number to reflect the actual miles, instead of it looking like it has an extra hundred thousand on it.

951rook

http://www.clarks-garage.com/shop-manual/ign-02.htm
with it pulled apart, you should be able to find a way to roll is back. it may not be as easy or quick as you'd like, but do what you gotta do.

I just pulled my cluster apart, took the speedo out, everything looks PERFECT, so i doubt it has anything to do with the cluster itself. apart from the harness that attaches to the back of the cluster, where should i put my multi meter to use?

MooreBoost

the yellow wire next to the power steering pump is the oil level gauge and plugs into the oil pan next to the drain plug. i would check all your grounds for any electrical problems.

MooreBoost

nope. there should be a weird lookin washer that the sensor and bolt go through to take up that gap.

951rook

^^ nice, that may get rid of the check engine oil light. pulled the speed sensor, the only washer there was a brass or copper one about 1/16 inch think. hmmm. Here's a couple pictures of the sensor face, and a lovely hole just below the dg and bg sensors.