Just a couple questions

[joeys928]

So I've been driving my 928 for a couple months now and i finally have some time to fix a few of the issues I have. I went through and replaced the timing belt and the engine looks and seems to run pretty good. I`ll just list some of the things ive noticed while driving it.
-It does idle high when I'm in neutral, but once I'm in in drive it idles perfect. Other than being really shaky.
-The power steering whines a lot and very loudly, I filled it up with new fluid and replaced the belt but those did not help.
-I'm not sure if this is just the cold weather, but it warms up very slowly. I believe its because the radiator fan is always on but i could be wrong. I`d leave it running for 15-20 minutes before leaving in the mornings and it would barely warm up at all.
-I've noticed that when it does warm up it runs a lot better but it feels like there are some performance issues. On takeoff it likes to go really slowly even with my foot to the floor then it suddenly picks up and goes.
-When i do try and give it a little gas trying to pick up speed or go up a steep hill it shakes really bad, and barely gets any faster.
-It still shifts pretty hard too, even after filling it with more transmission fluid and replacing the filter. Also it doesn't shift until i let off the gas unless it hits 4-5000 rpm.
-My windows, front wipers, sunroof, and brake lights don't always work. They used to work all the time but not rarely ever do. I'm getting 14-14.5 volts at the battery but if it sits for more than a day without being driven the battery is dead.
-My sunroof when its working will turn and open by hand but the little rubber piece that connects the motor to what turns to open it is ripped and I'm not sure how to find a new one or fix it some other way.
-lastly the rear wheel bearing needs to be replaced, I already have the parts i just need to know if there's anything different from any other car to look for or do when i change it.
If anyone can help me fix these problems that`d be great. Thanks for taking the time to read this. Oh and i forgot to mention the car is an `85 auto and I'm located in West Des Moines Iowa

[JhwShark]

Something is not right. I am not that up on your MY. But timing sounds like an issue or vacuumn maybe fuel. You also have less significant issues to deal with.

Someone may jump in with a little guidance. Check your timing, vacuum lines, fuel distribution, compression. You indicate a timing belt refresh; if these engine behaviors happened after that check your cam configurations first. Hopefully a configuration issue and not a failure in the valve train.

I hope you are a gearhead

[stepson]

Originally Posted by joeys928

-It does idle high when I'm in neutral, but once I'm in in drive it idles perfect. Other than being really shaky.
High idle typically means a vacuum leak. Unmetered air is entering the intake area
-The power steering whines a lot and very loudly, I filled it up with new fluid and replaced the belt but those did not help.
The reservoir has a built-in filter that clogs over time. The whine and groan could be your steering pump being starved for fluid. Replace your reservoir and refill with A/T fluid.
-I'm not sure if this is just the cold weather, but it warms up very slowly. I believe its because the radiator fan is always on but i could be wrong. I`d leave it running for 15-20 minutes before leaving in the mornings and it would barely warm up at all.
Don't trust the gauge. Use an IR gun to confirm at the top and bottom of the radiator
-I've noticed that when it does warm up it runs a lot better but it feels like there are some performance issues. On takeoff it likes to go really slowly even with my foot to the floor then it suddenly picks up and goes.
Check that your Temp 2 sensor is in spec. Could also be a vacuum leak/unmetered air issue
-When i do try and give it a little gas trying to pick up speed or go up a steep hill it shakes really bad, and barely gets any faster.
Sounds as if it's not running on all cylinders. Check/replace your spark plug wire and ends. Have you had your injectors professionally cleaned? Consider it
-It still shifts pretty hard too, even after filling it with more transmission fluid and replacing the filter. Also it doesn't shift until i let off the gas unless it hits 4-5000 rpm.
Hard shift indicates a mis-adjustment of the transmission Bowden cable and /or vacuum leak. There is a vacuum line that travels from the brake booster area down the top of the torque tube to the transmission. Test the ability of that line to hold vacuum
-My windows, front wipers, sunroof, and brake lights don't always work. They used to work all the time but not rarely ever do. I'm getting 14-14.5 volts at the battery but if it sits for more than a day without being driven the battery is dead.
Have you cleaned your grounds? If not, clean them all. Have you cleaned the fuse connections at the Central Fuse Panel?
-My sunroof when its working will turn and open by hand but the little rubber piece that connects the motor to what turns to open it is ripped and I'm not sure how to find a new one or fix it some other way.
Why not just save this fix for another day?
-lastly the rear wheel bearing needs to be replaced, I already have the parts i just need to know if there's anything different from any other car to look for or do when i change it.
This job can be a Bear without the proper tools. I just did this using a Sir Tools hub/wheel bearing tool made specifically for the 928 and it was not a lot of fun. The tolerances are very close on these cars. The freezer will be your friend.
If anyone can help me fix these problems that`d be great. Thanks for taking the time to read this. Oh and i forgot to mention the car is an `85 auto and I'm located in West Des Moines Iowa

Put your car model information in your signature line.
Good Luck

[Danglerb]

Originally Posted by joeys928

-My sunroof when its working will turn and open by hand but the little rubber piece that connects the motor to what turns to open it is ripped and I'm not sure how to find a new one or fix it some other way.

Ouch, 911 624 103 00 the sunroof "clutch" is Porsche only part about $130. Pelican has them, but price seems nuts to me, I would be looking at alternatives. Used is a first thought, but, used 30 year old rubber doesn't seem too smart.

[joeys928]

Thanks all for the help. Ill get to work looking at it and ill hopefully get everything done smoothly. If i need anymore help ill definitely be back to ask. I did notice one thing, most of the suggestions to fix my problems were through vacuum leaks. So is there a point that they are connected that would cause all these problems or is it just multiple leaks? Again thankx for the help i really appreciate it.

[stepson]

Joey,
There should be a diagram of your vacuum system on the decal on the underside of your hood. As you can tell from that diagram, it is a complex and far-ranging system and leaks can occur anywhere. Check over by the brake booster. There is a small vacuum line leading to a blue one-way valve. Check the operation of that one-way valve. That can cure a lot of ills of accessory-type stuff. Engine vacuum leak stuff is more typically MAF boot and large vacuum lines split/cracked/unplugged.

[Danglerb]

One of the reasons vacuum leaks get suggested so often, besides matching symptoms, is that there are so many places for small leaks to occur. Best to replace all the old hard rubber with new.

[MPDano]

Originally Posted by joeys928

So I've been driving my 928 for a couple months now and i finally have some time to fix a few of the issues I have. I went through and replaced the timing belt and the engine looks and seems to run pretty good. I`ll just list some of the things ive noticed while driving it.
-It does idle high when I'm in neutral, but once I'm in in drive it idles perfect. Other than being really shaky.
-The power steering whines a lot and very loudly, I filled it up with new fluid and replaced the belt but those did not help.
-I'm not sure if this is just the cold weather, but it warms up very slowly. I believe its because the radiator fan is always on but i could be wrong. I`d leave it running for 15-20 minutes before leaving in the mornings and it would barely warm up at all.
-I've noticed that when it does warm up it runs a lot better but it feels like there are some performance issues. On takeoff it likes to go really slowly even with my foot to the floor then it suddenly picks up and goes.
-When i do try and give it a little gas trying to pick up speed or go up a steep hill it shakes really bad, and barely gets any faster.
-It still shifts pretty hard too, even after filling it with more transmission fluid and replacing the filter. Also it doesn't shift until i let off the gas unless it hits 4-5000 rpm.
-My windows, front wipers, sunroof, and brake lights don't always work. They used to work all the time but not rarely ever do. I'm getting 14-14.5 volts at the battery but if it sits for more than a day without being driven the battery is dead.
-My sunroof when its working will turn and open by hand but the little rubber piece that connects the motor to what turns to open it is ripped and I'm not sure how to find a new one or fix it some other way.
-lastly the rear wheel bearing needs to be replaced, I already have the parts i just need to know if there's anything different from any other car to look for or do when i change it.
If anyone can help me fix these problems that`d be great. Thanks for taking the time to read this. Oh and i forgot to mention the car is an `85 auto and I'm located in West Des Moines Iowa

That's a lot of "couple" questions. Your in good hands.

[hobbyshark]

MP Dano you think that bucking and shaking could be TPS sensor placement on the throttle body?

[MPDano]

Originally Posted by hobbyshark

MP Dano you think that bucking and shaking could be TPS sensor placement on the throttle body?

Put your model year in your signature so it will be a lot easier to troubleshoot. Lot's of changes throughout the years. Vac leaks is what I would sort first. Full intake refresh with fresh silicone or rubber first. Since I don't even know what year your car is, it may not even have a TPS.

[neil30076]

Leo, in first post " 85 auto" and it does have a TPS.
Hobbyshark:
WSM vol 1A page 24-115 for TPS check procedure.

Check the Temp II sensor as well, that could very well be causing your problems. WSM 1A page 24-114.

Neil

[MPDano]

Originally Posted by neil30076

Leo, in first post " 85 auto" and it does have a TPS.
Hobbyshark:
WSM vol 1A page 24-115 for TPS check procedure.

Check the Temp II sensor as well, that could very well be causing your problems. WSM 1A page 24-114.

Neil

Thanks Neil, just trying to get Joey squared away so it will follow whenever he posts. Looking at first posts or other threads trying to figure out MY is not the best way to get help.

Neil knows the 85 well as he has one. I'm not really up on all the sensors they have.

[joeys928]

Thanks for all the replies so far. They have really helped me out in getting this project underway. I was thinking earlier that it would probably be easier and best for me to just go through and replace all the vacuum lines, as Danglerb mentioned. I just need to know how much of what size hose is needed. Also if ill need any new connectors or if the old ones will work fine.

[neil30076]

Originally Posted by joeys928

Thanks for all the replies so far. They have really helped me out in getting this project underway. I was thinking earlier that it would probably be easier and best for me to just go through and replace all the vacuum lines, as Danglerb mentioned. I just need to know how much of what size hose is needed. Also if ill need any new connectors or if the old ones will work fine.

This diagram is from a kit i believe roger supplied a few years ago:

[Danglerb]

Roger has a preassembled kit, highly recommended. Home - 928s R Us Porsche Parts Store he uses MB couplings and good quality hard nylon tubes.

[syoo8]

Roger's kit includes the necessary vacuum junctions, but is not preassembled. You have to cut the hose yourself and route it.

[Danglerb]

Originally Posted by syoo8

Roger's kit includes the necessary vacuum junctions, but is not preassembled. You have to cut the hose yourself and route it.

Really? Mine was ready to go, maybe varies on model etc?

[Alan in AZ]

From the described conditions I'd be wondering if its only running on one coil... or at least missing some cylinders - any gas smell in the exhaust?, any holes/plugs really wet?

Electrical issues sound most likely to be the ignition switch. Test CE pin F21* with the accessory/ignition on - any power there - does it vary when you wiggle the switch? any difference between accessory position and ignition position?

*Plug F - the bottom connector on the right side column. (BTW - this is for an '85 NOT all years)

Alan

[joeys928]

there is difference when i have just the car on everything works, but once i start the engine it doesnt work anymore. I was thinking to check in the ignition if cleaning all the grounds and the rest of the connections didnt help.