have you unplugged you Idle control valve to make sure that is not the problem. I had trouble with mine at one point and it caused very low idle. If you unplug it the idle will be high but will dip when you push in the clutch at stoplights and when you have the A/C on. It is a good test to see if that is your problem.

Re the oil in the spark plug holes been there and done that. Time to replace all of the sealing rings and gasket for your cam cover. Not a hard job but if you do it be VERY careful of the torque specs for the hex bolts that hold in the cam cover. Over torque them even slightly and they will snap and it is next to impossible to get them out. A small torque wrench is your friend here.

Once you have the cam cover off check the cam chain tensioners if they look worn change them. There is a good DIY on rennlist.

the car dies at idle sometimes and sputters mid rpm i from what i have read i think it may be the tps sensor. i have one on order. fingers crossed

I would bet your DME/ECU is on its last legs. See the details below:


These are some examples of the damages that we see on most ECUs:

Water damaged ECU
Fire or Short Circuit damaged ECU
Broken Pins on the ECU
Broken tracks on the ECU
Cold Solder Joints on the ECU
Corrosion on the surface of the ECU

Many other symptoms may occur that can drastically lead to an ECU failure such as:

Erratic idle
Stalling
Poor running condition
Excessive fuel usage

We recommend testing or replacing the following:

Ignition coils or ignition module
DME Relay or the Main Relay
Faulty spark plugs
Fuel injectors
Idle control valves
Reference sensors
Air flow or mass flow meter
Throttle position sensor
Power supply
Grounds

There is your laundry list to check of which you have done most.

Posting to an old thread for future reference for others. I had the same problem, won't hold idle and stalls intermittent and only when hot. 1990 944S2 Cab.

I pulled out the diagnostic manual and started checking things and found an intermittent throttle position sensor. The idle switch would not short out when the throttle was closed when the switch got hot. The resistance became thermally influenced on the 25 year old position sensor. The TPS resistance at full throttle was specified to be under 10 ohms and mine was 16.6 when hot but only about 5 when cold. So it ran fine when cold but when hot failed.