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Wayne 962 Wayne 962 is offline
Author of "101 Projects"
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More progress on the 959...

A brief update: Last night I spent about 5 hours reading the factory workshop manuals to try to figure out how to build a diagnostic code reader for this car. Then this morning, I got the information emailed to me (violin959 - thanks Bryan!). Tony Callas from Callas Rennsport also offered to help me with the box too. I was very close in my "guesses", but I had made a few mistakes that might have damaged one or more of the computers if I had tried to plug the box in. With the new information in hand, I modified the box I wired last night, and successfully read and cleared the Motronic trouble codes.

Unfortunately, one of the codes was "Motronic unit damaged - replace unit". Well, we'll just ignore that one for now, and hope it doesn't come back.

The trouble lamp is still on, on the dashboard, I'm assuming that's related to the trouble codes in the drive-control system. The procedure for clearing those faults seems somewhat complicated, and I will probably have time to do that tomorrow (before I take my kids to Disneyland!).

Anyways, having a functioning box is of paramount importance - you can't really work on these cars and figure them out without it. I did drive the car today, and there was indeed something wrong with the first-stage turbo. I'm not an uber-expert on turbos, to the point where I can figure out what is wrong just by listening, but my first guess was that it sounded like the wastegate was stuck open. Boost pressure was only at .5 bar absolute, which is lower than atmostpheric pressure. Didn't seem right to me, and the car at lower RPMs had no real power. The upper end is still very strong, but the lower ranges are sluggish, to put it mildy. I'm looking forward to working on this, I need to remove the rear bumper to access all of the exhaust and turbo machinery - I suspect that will make a really, really neat photo when that's off. Also, I need to hook up a boost pressure gauge to test the total boost (gauge in the dash isn't accurate enough, supposedly, from the factory manuals). The factory test procedure actually calls for you to drive around on a flat surface and floor it while braking at the same time. Odd, but I guess a rolling dyno is out of the question since this is a 4WD vehicle.

I wanted to button up the driver's side door today, but I found that the electronic door lock microswitch was broken, so I had to order a new one for delivery tomorrow morning. Hopefully, I'll get this installed and working, and then I can button up the driver's side door and not worry about it again for a long, long time. After that, if I have a few moments, I'll put the new hood crest on the car (The one I have is made in Germany).

Here's one of the plugs under the seat that accepts the diagnostic box. It's a six-pin connector that's similar to the one used for the power seat harness.

Here's a photo of my box plugged in and working. Today I read and reset the codes for the first time...

Closeup of the microswitch that is broken. New ones are $75 in the Pelican catalog...

Here's where the microswitch goes, it wraps around the door handle:

Here's the door handle and microswitch that broke:

Here's a photo of the passenger side window switch hooked up. It didn't work when I first put it back together. I then started checking fuses, before I remembered that power is routed through the driver's side switch, so if that switch is broken or disconnected, then the passenger side window won't work.

Here's what the driver's side window switch looked like. If you're going to have the wires hanging like this, it's a good idea to pull the fuse for the window motors so that you don't accidentally ground a live lead.

Wayne R. Dempsey, Founder, Pelican Parts Inc., and Author of:
101 Projects for Your BMW 3-Series 101 Projects for Your Porsche 911 How to Rebuild & Modify Porsche 911 Engines 101 Projects for Your Porsche Boxster & Cayman 101 Projects for Your Porsche 996 / 997 SPEED READ: Porsche 911 (October 2018)

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Old 10-18-2007, 12:12 AM
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