jerybak

I purchased a 1987 S4 Auto that had sat for about 18-24 months outside in the midwest. replaced the battery, fuel pump, fuel filter, starter, small fuel line from tank to filter, oil/filter, oil pressure switch & sending unit, hood & hatch struts. Got it running.

I have ran 2 cans of 44k decarbonizer through it currently, been a daily driver for 10 days or so, drove it for about 2hrs straight on local highways stopping about every 15-30 mins at gas stations to check for any issues, all was good...

Flappy works, car is starting good, no more long cranks, idles a little rough not sure why, transmission may need some fluid as it really kicks when I put it in gear, like damn near chirps the tires in the garage. Can i check fluid level without a lift?

Car has 60k miles on it, I have these parts and I am planning on the following this weekend: steel brake lines, decarbonize CE panel & install all new fuses & replays, fuel rail fuel pressure gauge, new window sunroof & wiper switches.

After reading for many hours I have way to much info and need some guidance. Wondering what to do next, originally I was thinking new injectors to help smooth out the idle, now I am thinking knock sensors and or MAF, still running the plugs that were in it as they were not terrible but still need to check if plug wires are ok as they look fine by the eye test, also looked into replacing all rubber lines under the hood and already got prices from Roger @ 928RUs for rubber goods.

Now I am reading about top end refresh, and the $1k in parts needed to do it the correct way...... I also like the X Pipe for a little bump in the RWHP.

Then i started in on the Flexplate clamp/ thrust bearing issue & with 60k and no record of a timing belt change I am thinking of installing a PKT-B - advanced timing belt tensioner.

Also car doesn't have a belly pan on it....do most folks run with a belly pan?

Also looks like I have a vacuum actuator issue as I am getting hot air from the center vents with the HVAC off, and a very annoying taping/ ticking noise from the center vents.... can I stop the damn noise for now and attack the actuator issue later?

Also is there any reason/ benefit to refresh the EZ-K or LH if I have no plans for superchargers/ major engine mods, and they don't seem to be presenting any issues currently?

FredR

The two most critical items on these cars [in my opinion] are the torque tube clamps and the timing belt. The former can wreck the engine, the latter the valve gear.

At this moment in time one presumes you do not know whether the flex plate clamp is holding [or not] so you need to take some action to secure this item. Whilst at it replace the rear pinch bolt and ensure that assembly is correctly installed.

The timing belt is also a must if you do not know the provenance of this item and most replace the water pump while they are at it- if you can do the job yourself and are willing to take a chance you can leave the water pump as is if physical inspection suggests it is OK but many have found the pump to fail when a new belt is fitted.

The choice to run with the stock tensioner or a PKT is pretty much down to you. You need a tensioner device that works and if you are going to change the belt then that is a good time to change the tensioner if that is your choice. Plenty of discussion on this topic and no desire to get involved in that one.

Clearly you understand the concept of the injectors flowing correctly and the MAF reading correctly, and to get the motor to run correctly you also need the ignition leads, the knock sensor, the Hall trigger and the fuel pressure regulator/dampers all in good working condition as each item can degrade performance.

Suggest you read Mike Steiner's excellent thread on his exploits taking his S4 from quisling to beauty if you have not done so already as he has covered all the bases in exemplary fashion.

Refreshing the inlet manifold is also a sooner or later must have item. You cannot do the knock sensors without removing this item so again, planning this into your journey can only be a good thing. The best way to improve the appearance of the engine bay is to powder coat the inlet manifold and cam covers.

Rgds

Fred

Adk46

The combination of unknown thrust bearing preload and drive-line shock from the harsh shifts may be the most serious issue you face (an assertion I make cautiously). I must sort out my own harsh shifting this winter - I'll get my vacuum leaks under control first with the top end refresh procedure (per Dwayne's guide), but a visit to a transmission guru is probably unavoidable.

My understanding is that outright belt failure is rare; failures are more likely to arise from tensioner or water pump failures. Some water pump failures can wreak their own havoc on the block....

You don't need a lift for anything. You want a lift for everything. If having your own lift seems foolish, too late: you've already done something much crazier.

Here's wishing you a long winter to complete your to-do list. Good luck!

Adk46

Oh - the belly pan: if and when I get everything sorted on my car, I might reward myself with a new front unit (MIA) (or the full unit that someone is producing). Until then, a pan will just be a hindrance.

The chin spoiler is more important - if you have one, it is probably smashed like mine was. Mine was made from rubber and I could not weld-repair it, so I patched it with some good marine-grade epoxy and fiberglass. It would already be smashed had I not added skid plates. These might not be so necessary, except that either a PO lowered my car, or the springs have sagged. My adjustors are corrosion-locked.

Mrmerlin

Curt if your getting harsh shifts and the fluid level is good then its a good chance one of the vacuum lines is disconnected on its way to the transmission vacuum modulator.

the most common disconnects are at the top of the bell housing,at the 7 way splitter,
and then where the flex line meets the hard line at the front of the TT,
then where the flex line is connected at the rear hard line.
NOTE the hard line runs down the TT.
NOTE its best to just install fresh line to all of the flex areas.
NOTE the flex line can also snap as it passes over the top of the transaxle.

For the OP dont drive the car until you have verified that fluid level in the trans.
NOTE if its low you will permanently damage the clutches.
the car has to be level and the engine running to check the level,
its best done on a lift ,
otherwise 4 jack stands work.

The rough idle is most probably a bad ignition wire,
replacing the whole set is best,
I suggest to buy the best set you can,
its a plug and play set made by Beru its about 400.00,
also it includes new coil wires.
NOTE on the coil wires make sure they do not touch anything on their run to the caps.

As previously noted make sure to check the drive shaft pinch bolts both front and rear for proper torque.

MainePorsche

^ What these guys said.
Also, GET a belly pan.

jeff spahn

If you do all you mentioned OP. You will have a well sorted car. (Clean grounds and new ground strap also)

M. Requin

If you want to keep it for a while, I would bump fuel lines to the top of my list.

worf928

Follow MrMerlin's advice: check the fluid and make sure the vacuum to the shift modulator is connected from transaxle to intake air guide.

The longer you drive with the hard shifts the higher the probability you will damage the flex plate or snap the drive shaft.

While you have it on stands checking your transaxle fluid level, release the tension on the flex plate, measure crank end play, and check all the pinch bolts.

These are the things I would have done to an auto 928 before anything else and before driving it more than absolutely necessary.

GlenL

Ya wanna fix it or drive it?

I'd replace the timing belt if there's no history on it. They'll look "good" for a long while after the change period of 5 years.

Then I'd drive it and fix things one-at-a-time as I felt like it. Some of those driveability issues may be just because it's sat.

docmirror

Driveline now, use new bolts for both clamps, instal added clamp of your choice.
Timing belt and water pump soon. Check cond of left cam gear carefully.
Fuel lines(inspect now) soon, kit from Roger is da bomb.
HVAC stuff later, as required. Will include new modified water shutoff valve for hot air from vents. Also need vac actuators and maybe some vac lines.
Top end refresh later, as you allocate funds.

ltoolio

Dwayne's got a really nice write-up on the Flex Plate check.

MainePorsche

Put the lower bellhouse cover back with 4 bolts so you can more easily check the tension. Will make sense once you read Dwayne's write up.

jerybak

Ok made the following choices, thank goodness a buddy of mine access to a lift and I am having the parts for below shipped out asap, trying to get everything here for this weekend. If my minor rough idle doesn't disappear after the NOW list I may bump numbers injectors & MAF to NOW list.

NOW
1. checking trans fluid
2. checking crank end play
3. replacing Flex Plate Clamp (Ritech)
4. replacing TT & Clutch Bolts
5. replacing fuel regulators/dampers
6. replacing all rubber fuel, coolant, transmission lines (928 RUS Kit)
7. installing new Beru ignition wires & new copper plugs
8. replacing vac lines (928 RUS Kit)
9. install new ss braided brake lines (Goodridge HP)

NEXT
10. Water pump/ timing belt/ tensioner
11. Belly pan
12. install new injectors
13. MAF (OTTs maybe??)
14. OTT Pipe

Please have a look and let me know if i should add something to the NOW list if it makes cents to perform it while all the other stuff is going on.

FYI....PO sent a copy of a 2010 service ticket that states, new alternator was installed, cleaned throttle body, installed new plugs, caps & rotors. Replaced engine reference sensor, then from 2010-2012 he put about 1500 miles on it, then it sat till a month ago when I started in on it.

worf928

That's the only thing in your now list that I question. They do fail. But, not often. I've seen exactly one failure out of ... low-hundreds.

Rough idle:
coil wires, plug wires
injectors need cleaning (bad spray pattern due to varnish) or leaking
MAS out-of-spec
O2 out-of-spec
TEMP-II out of spec
carbon build-up
after-market chips
dying crank speed sensor

... the list goes on in decreasing probability.