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So I dug into the audio a bit to see what I’m dealing with here. Looks like the decision for stock vs. aftermarket has already been made for me.
Stock amp is still in place, but not sure if I’ll keep it or replace. Since I’m updating every other component, I’ll probably update this one as well.
Amateur crimping going on there. The kind I did in high school. Hmmm…. This is all lower priority to mechanical and electrical, but was curious what I had as a starting point.
Congratulations! The 90/91GT is probably the pinnacle of the line. You've got a lot of work ahead to really get it humming but it is a great car.
Some of your items are not like the others. Your hatch problem might just be the plastic spacer on the lower bracket, $40 and 1 minute to fix (newbie check: you know the "button" is pulled not pressed, right?).
Intake refresh is a pretty big deal, with about $2K of parts and multiple vendors involved. It is an extremely rewarding exercise and it was the first big job I did myself. It results in practically a new engine. Worf928 has an excellent writeup that is online somewhere and I followed it to the letter. The subject car was a 90GT. Dwayne's Garage has another one for an '87 S4. Plan to replace the fuel lines, thermostat, and oil filler neck, rebuild the MAF, and replace all parts and hoses under the intake with new. There are refresh kits from the major 928 specialist vendors.
On this car more than others, routing the hoses and even orienting the clamps is challenging, so take a lot of pics whenever disassembling anything.
Personal opinion: Audio is very important and the OEM stuff is not up to snuff. I recommend to rip and replace everything unless it's already very good aftermarket. A stock aficionado will pay a lot for that ancient technology amp, head unit, speakers, and maybe even crossovers, and you will have better sound and a profit.
Last edited by chart928s4; 06-04-2022 at 12:04 PM.
Today I dove into the PSD. It didn’t take long to find the problem.
Reservoir was bone dry. Filled it up with new brake fluid and starting bleeding the system per this excellent write up: http://www.928intl.com/repair/psd1.pdf
Got lots of foam at first, but soon the brake fluid started flowing through. Hardest part of the procedure was getting a 7mm on the bleed valve for the PSD slave cylinder. Got foam there too until the new fluid flowed through. I didn’t get a chance to test drive it afterwards, but hopefully tomorrow.
Happy to report that on my test drive today, I got a green PSD light on a tight turn where I would expect to get one! Happy that was an easy and cheap one to knock off the list.
Got some quality garage time on Saturday and took the shields off to have a good look around. Also first time I jacked up the entire car to take a good look around. Went ahead and did oil and filter and then changed the diff oil. Happy to report not too many new issues found. Shields had collection of OEM and non-oem bolts. (No surprise). Exhaust is in much better shape than I thought save the lack of a muffler. I’m shopping around for either a used OEM or aftermarket. Haven’t decided.
Two new issues found were a coolant leak from the pressure switch 928.641.513.00 (appears to be a common failure point based on the threads I saw) and I found the alternator cooling hose 928.603.143.04 was chewed to bits. Someone had just stuffed the remnants into the cooling duct. Seriously doubt much air was getting through there.
Will get parts ordered to fix both of those issues. Both look easy.
Got it. Adding fuel lines and Petza’s suggested lines to the list. I need to research those to see when I can work them into the plan.
Today I dove into the PSD. It didn’t take long to find the problem.
Reservoir was bone dry. Filled it up with new brake fluid and starting bleeding the system per this excellent write up: http://www.928intl.com/repair/psd1.pdf
Got lots of foam at first, but soon the brake fluid started flowing through. Hardest part of the procedure was getting a 7mm on the bleed valve for the PSD slave cylinder. Got foam there too until the new fluid flowed through. I didn’t get a chance to test drive it afterwards, but hopefully tomorrow.
You’ll notice the extra wire near the PSD. It appears to be an attempt to ground. It disappears into the light on the left rear bumper. Looks like an attempt by someone to bandaid an issue. I’ll get to that later.
Also wanted to show y’all a picture of my “custom” exhaust.
Look Ma, no muffler! It just pipe from the small silencers. Notice the nice rust holes in the pipe. The word “janky” comes to mind. I will replace / update.
Keep in mind that brake fluid, in the PSD system, does not evaporate.
Loss of fluid means only one thing...there's a leak.
The most common leak is the slave cylinder on the side of the transmission.
The second most common leak is the flexible hose to the transmission.
The other thing which occurs, commonly, is that the pressure accumulator splits at the friction weld and sprays out fluid at high pressures.
Keep in mind that brake fluid, in the PSD system, does not evaporate.
Loss of fluid means only one thing...there's a leak.
The most common leak is the slave cylinder on the side of the transmission.
The second most common leak is the flexible hose to the transmission.
The other thing which occurs, commonly, is that the pressure accumulator splits at the friction weld and sprays out fluid at high pressures.
Thanks, Greg. I suspect it is the slave cylinder, but the underside is so filthy it's hard to tell just where the leak(s) are coming from. I'm going to keep an eye on it and see if I can pinpoint the leak.
Thanks, Greg. I suspect it is the slave cylinder, but the underside is so filthy it's hard to tell just where the leak(s) are coming from. I'm going to keep an eye on it and see if I can pinpoint the leak.
There's a vent hole drilled into the slave cylinder, so if it leaks brake fluid past the internal seals, the fluid can escape and not be forced past the rubber bellows inside the transmission.
This "weep hole" is directly under the center of the slave, close to the mounting flange.
Congratulations! The 90/91GT is probably the pinnacle of the line. You've got a lot of work ahead to really get it humming but it is a great car.
Some of your items are not like the others. Your hatch problem might just be the plastic spacer on the lower bracket, $40 and 1 minute to fix (newbie check: you know the "button" is pulled not pressed, right?).
Intake refresh is a pretty big deal, with about $2K of parts and multiple vendors involved. It is an extremely rewarding exercise and it was the first big job I did myself. It results in practically a new engine. Worf928 has an excellent writeup that is online somewhere and I followed it to the letter. The subject car was a 90GT. Dwayne's Garage has another one for an '87 S4. Plan to replace the fuel lines, thermostat, and oil filler neck, rebuild the MAF, and replace all parts and hoses under the intake with new. There are refresh kits from the major 928 specialist vendors.
On this car more than others, routing the hoses and even orienting the clamps is challenging, so take a lot of pics whenever disassembling anything.
Personal opinion: Audio is very important and the OEM stuff is not up to snuff. I recommend to rip and replace everything unless it's already very good aftermarket. A stock aficionado will pay a lot for that ancient technology amp, head unit, speakers, and maybe even crossovers, and you will have better sound and a profit.
Unfortunately, it looks like the hatch is not just the plastic spacer. The motor will run with I pull up the release ***** and I can see an output shaft turning, but the vertical bar isn't moving at all. So either it isn't in contact or something is stripped. It's not urgent, so I'll live with it for now. I have bigger fish to fry at this point.
Not sure I've seen Dave's write up on the intake refresh, but I have studied Dwayne's. If anyone has a link to Dave's (@worf928) please let me know. I searched, but didn't find it.
Originally Posted by RennHarry
Wow. What a car.
And what a list! Way outside my comfort level to DIY, but you can save a boatload doing it all.
Following.
Cheers
I'll be taking it slow and probably asking lots of rookie type questions along the way, but I enjoy getting to know the car this way. It's also a bit like therapy.
Originally Posted by RennHarry
JBT3, that looks like 928 Christmas!
Cheers
Costs a lot more than we normally spend on Christmas! But will be worth it.
Originally Posted by GregBBRD
There's a vent hole drilled into the slave cylinder, so if it leaks brake fluid past the internal seals, the fluid can escape and not be forced past the rubber bellows inside the transmission.
This "weep hole" is directly under the center of the slave, close to the mounting flange.
Thanks again, Greg! I will start to research the slave cylinder and see if it can be rebuilt or if I just need to replace. Will come back if I can't find answers.
Originally Posted by 928cs
The GT is my favorite regular version of the 928. And this one seems to be in good hand, now.
It wasn't before, obviously.
May I suggest to keep the original wheels?
Thanks! I wasn't really looking for one to save. Got carried away in the auction, but it's mine now and I'm happy to save one, especially a GT. Looking forward to the day when I can drive it like Dr. Porsche intended.
05-29-2022, 11:29 PM
