Gary R.

I know the 89, 90, and 91's have no head gasket and suffer from the DMF (EXCEPT for 89, no DMF) and distributor ozone problems unless addressed but when did Porsche change this? As far as I know it wasn't before 93 but i'm hearing different things. Anyone have the scoop, maybe by VIN number?

Thanks!

Gary R.

Ok.. thank you. What I need to know is when, AFTER 1991, they fixed the problems.

jimq

the headgasket was fixed late 91 model

Gary R.

Hmmm, wonder if mine has a headgasket?? It shows very minor "seepage" on 4,5,6 side but thats it. PPI guys have said to do nothing and that it is nothing to be concerned about. Anyone have a build date in 91 for the cutoff?

Dunasso

In 91 the issue was fixed at the factory and others were repaired at the dealerships when and if they were scheduled for the repair by the PO. My car is a 91 also, I found out that I was fortunate enough for mine to have been done on the assembly line. I dont have the vin handy but it was born in August 91.

You can go by a local dealer, have them run the vin to see if your car has had the head work done already. However, you should have the head studs checked and if possible retorqued since you have apparent issues with current leaking.

It is important to realize that if the engine runs too long with loosened studs, it will cause leakage around the mating surfaces of the cylinder head and jug. It could also cause the jug to wear into the head which would then have to be resurfaced. At this point it is not uncommon for the head to warp.

Hopfully a retorquing is possible and solves your delima.

Duncan

Gary R.

Think i'll have Dan Jacob's shop do it next week, see what happens. Car runs so nice and is so tight i'd hate to screw it up by simply not trying the re-torque. I'll also check with Danbury Porsce on the date issue, but I have serios doubts about them having a CLUE, and they are a good dealer!

Dunasso

Any authorized Porsche dealer should be able to get that info for you with no problem. As for whether or not they charge for it is up to them. But the info is there on the Porsche database and every Authorized Porsche dealer has access to everything thats ever been done and recorded to your pride and joy.

Duncan

JasonAndreas

The 964 was gasket-less up until engine serial number: 62 M06836 for those with manual transmissions and 62 M52757 for those with tiptronics. If the work was done under warranty than the machine shop should have marked a -10 or -20 (the amount of inner surface that was removed) at the top of the cylinder head on the intake flange. Unfortunately you'll need to remove one side of the intake manifold to see that marking.

The C2 was delivered with the LUK flywheel in late 1992, from 1991 up until that time it came with the modified Freudenberg and before that with the original Freudenberg. The C4 was never delivered with a LUK flywheel but Porsche did switch to the modified Freudenberg in 1991. The ventilation for the ignition distributor was started on the production date August 13, 1993 with engine serial number 62 R00592 (5-speed) and 62 R50520 (tip).

Bill Wagner

Gary:

I have a '91 with the updated engine. It was built in January of 1991, and the serial number on the engine indicates that it was several thousand units into the updated production run. My guess would be that about the first 1/3rd of the '91s have no head gasket. The post above give the serial numbers for the engine, and it's stamped on the right side pillar of the little aluminum "beams" that support the fan.

Gary R.

Thank you Jason (and Bill), that is exactly the info I was looking for... going to check it now... very hard to see but the digits I can make out are M05898*(a star). there are a couple digits above that but without removing the A/C no way am I going to see (maybe a magnifying mirror).. off to NAPA I go later on, but according to the numbers above I have the "lighter" head assembly... .

mxbanker

This issue is like "flogging a dead horse" if they leaked they were usually fixed if they didnt leak they didnt need to be fixed. Many cars AND motorcycles have this design (no gasket)
Thats my .02 c