What to do while engine out? 996.2 3.6
 

I am repairing the 996 Targa of my old man to make it reliable again. It has been leaking coolant and oil, so I identified the main problem to be the AOS. Changing it didn't go well because a previous workshop had over torqued and stripped out one of the AOS screws :mad:

Therefore, the engine had to came out, and I am doing preventive maintenance as working on the engine while it's in the car is a PITA. I need your knowledge and expertise on what makes sense to replace and what is not necessary. The car has 130000*km (ca. 80000 miles).

Already done:
- AOS
- Two pulleys
- Oil filler neck
- belt
- rear main seal (3 years/6000km ago)
- oil pressure sensor

To do:
- Waterpump
- Thermostat
- IMS (already bought the tools and bearing)
- transmission mount

Not sure:
- timing chain guides: Reasonable or overkill?
- oil cooler: Reasonable or overkill? Original one doesnt seem to leak and looks okay. See pictures below
- shift cable: The ends are rusted, also the clip holders are broken off. Could get cheap some from a Porsche 996 Turbo. Do they also fit the naturally aspirated engine?

The engine was very oily from the outside. I know I'll never get the engine completely dry, but I'd like to at least try. Can you tell from the pictures where the leaks are coming from? I would then simply replace the relevant seals as well.

https://i.postimg.cc/5yZmmq2P/IMG-20230425-162128.jpg

https://i.postimg.cc/S4gBt9pp/IMG-20230425-162156.jpg

https://i.postimg.cc/gkFS8mLG/IMG-20230425-162224.jpg

https://i.postimg.cc/jsXpTwwP/IMG-20230425-162146.jpg

Unfortunately, many questions at once, but I simply lack expertise with these vehicles. I would be happy if someone can answer at least some questions!

Replace the plastic coolant tank . So much easier with the engine out . Have the alternator tested . Replace the o-rings on the oil cooler.

Replace the starter alternator cable. It corrodes over time and makes it appear you have an alternator or battery problem or both. There are 16 coolant hoses around the engine. Examine them all.

Thanks for your tips! Ordered a coolant tank (not as expensive as I expected), O-rings and a coolant hose that had damage to it.

Will look into the alternator!

I hope you purchased a Porsche OEM coolant tank . There have been some problems with aftermarket tanks leaking . Some right out of the box .

I ordered a MAHLE-Behr one. Should be OEM quality?

No.

Take it outside and wash it?

Already did that :)

Engine is back in! I am getting Error Codes P1502, P1518 and P0638, so something with the throttle body??? Not.sure if there's a problem or if it has to be adjusted in some way

edit: problem was the connector! Car runs and no leaks as far!

It never hurts to do a throttle body adaptation . Turn the ignition key on but don't start it . Leave the key on for at least 60 seconds and DON'T touch the gas pedal . You may hear various noises as the system cycles . Then turn key to off position and remove . You are now good to go . But throttle body/ECU will still be learning/adapting as you drive for a while .

Did this procedure when I searched online for the problem.

BUT I have bigger problema now :(
I drove off with a normally filled expansion tank. When I returned, the tank was completely full and coolant was coming out of the valve at the top.
As a test, I removed the oil filler cap and found that there was a vacuum. I'm not sure what's normal, but it seemed very strong to me.
According to my research, it could be the AOS? :(

The drive itself went smoothly. Car idles fine, water temperature is as it should be and oil pressure sits at 1bar at idle.

A manometer is the tool needed to really diagnose the AOS . You can buy them for roughly 30 bucks .

Will buy one from Amazon...

I also read that there could still be air left in the coolant system? And that I should open the valve of the expansion tank and drive around like that? I didn't fill up the tank with some special tool or anything like that

Yes driving around with the expansion tank valve open helps the system burp . If you have an area you can drive with elevation changes that helps chase air bubbles out of the system .

The air in the system could be the cause for the overflowing coolant in the expansion tank?

Tried to bleed the system with this method: https://rennlist.com/forums/996-forum/513364-engine-coolant-bleeding.html

I got to point 9 or 10, the car turned on the fans, thermostat was most probably open and the coolant level kinda stable. All of a sudden coolant gushed out of the open cap, at least half a liter. I turned off the engine to clean up, and shortly after starting it again, the same thing happened again. It didn't seem like air was coming out, the coolant was just pushed out of the expansion tank? With the engine off, the coolant level sank about the same amount as coolant was spilled