jason '83 911

I'm currently looking at 996 (1999) with about 50k on the clock - I have the car booked in for a PPI (about $350).

My question is the whether to get the additonal compression test (another $300 on top) my gut feel is yes as against the total cost of the car it is insignificant and would provide peace of mind...any advise?!?!?

I've been lurking on this site for a few weeks now and have found so much great information, hints and tips etc - I will paying my membership fees as soon as I get my hands on a 911...

Eli K

If all else checks out compression test will likely not be neccessary, often the shop will help you make the descision...

aben8057

My thoughts are have the shop leave compression test for the later. If the first PPI comes back clean and you are 100% sure you will be purchasing the car then move forward with compression testing. Why waste the money on compression testing if the inspection comes back with issues.

My 2 cents

Shark

The guy that did my PPI said a compression problem would be detected by the car's electronics....ANOTHER reason the 996 is superior to previous generations.

pongobaz

Same issue for me. Mine is going in for its PPI tomorrow and when I spoke to the service manager, he said that he highly doubted that a compression test would be necessary if all else checks out considering the low mileage (39K Kms). Have your tech inform you if they feel it's necessary.

4s

Bought my 02 c4s a couple of months ago with 13,000 miles on it only to find out a month later that the valve guides were worn and they needed to replace the whole engine. Luckily it was covered under warranty.
300 bucks is a small price to pay esp since your car won't be under warranty. A PPI will not always catch this problem. $300 or $15000. No brainer if you ask me.
I wouldn't trust the service guy where your buying it any further than you could throw him. Obviously he/they want to sell the car, so they will not have your best interest in mind. Take it to a indi and have him do the PPI and test. He doesn't care if you buy the car or not. Not his inventory. Best wasy to get the "real" facts on your car. Good luck.

jason '83 911

The PPI is being performed by a indi Porsche Garage.....Thanks everyone for the sound advice - really appreciate it...its tough trying to not get caught up in the "must have 911 now" fever. I think the no brainer hits the mark...I'll discuss with the service manager first but will likely get the compression test. Again thanks and hopefully be posting some photos soon!

Pugnacious P

I have my car in for a PPI right now, and the broker of the car told me most PPI are around $200, including compression? Hmmm, yet the guy at Porsce independent did not even discuss price with me yet? I'll have to call tomorrow.

But I think compression a good idea with early MY 996's given poor engine track record.

Good luck!

Eli K

Problems with early engines were "catastrphic" meaning, a compression test wouldn't help detect them

pongobaz

Of course you shouldn't have the same place that's selling it do the PPI...uhh, can you say conflict of interest?! The Porsche dealer who is doing the PPI on mine is NOT the seller and the car still has 15 months original warranty anyway. Still, if the tech decides that it needs more investigation, I'll have it done.

TT Surgeon

Do it, the electronics may not pick up moderate ring leakage that will worsen with time. The CT should pick up valve seal issues as well. It's actually a very easy test to do, I've literally done it hundreds of times. You should have 5% or less variance cylinder to cylinder, make sure you achieve TDC when measuring your cylinder pressure. The gauge is about 20$, fwiw.

TT Gasman

What's the big deal about a compression test? It's a very simple procedure, takes no more time than changing the plugs.