993::hb

Looking at a c4S with ~70k miles

Did a PPI with the following results. How bad is this and what is this car worth? kbb for trade in is 38k in fair condition.

Not worried about transmission or chain housing leak but more about the cylinder #3 leak and base gasket leaks. How bad is that and when does this need to be fixed?

1) Under Leak down
Cyl #3 11% leak

High leak for cylinder Plug also lean discolored Possible burned valve


2) Check Engine
Oil leak at Cyl #1, #2
Base gasket leaks. The engine cylinders have to come off and possible machining to repair 1&2 repair together $8-13k

1)Heads off to do valve job. 2)Cylinders off to do Cylinder leak


3) Chain housing leak $1500-2000
Or included in above


4) transmission leak
Owner says work was done to repair this at dealer.
Reseal 1st and 2nd section of transmission
approx $ 2500.00 with engine/transmission assembly already out

Quadcammer

depends on a few things:

1. whats the price of the car? If you can get it for $25k at most and its in good shape otherwise, might not be so bad.

2. How willing are you to purchase a car that will need almost immediate repairs that could last a while? To me that kind of dampens my enthusiasm, but if you're ok with a "project" car, then have at it.

3. If the cylinder base leaks are minor, I wouldn't tear it down just to fix that. I have a bit of a base leak from the number 1 cylinder, but its hardly anything I'm concerned about. Literally just some oil mist on the case.

rg588911

Sounds like a lot of issues. Certainly there are plenty of good cars out there with similar miles with far fewer issues. That said, how well do you know the shop that performed the PPI? Some times (not often) shops use PPI's to generate business. The leak down numbers are not something you can fudge though. I would assume that if this PPI is right on, the seller should be willing to take a very low number. Something in the mid $20s sounds right for the cost and time and effort it will take you to just get this rig performing as it should. There are lots of people that are on this forum who will tell you to run and find the best car you can afford. I am different and enjoy these sorts of projects as you really get to know the car. Problem is that you need to purchase it cheap to account for all this. If a project is not for you, then the correct advise is run from this car. There are plenty others out there and spending $40k vs $32 will net you a big difference in car (better condition on interior, seats, paint, wear and tear items etc) and lots less headache. Also, cars that have these kind of problems are generally not cars that were cared for the way we would care for them hence we never know what other problems will pop up from lack of attention for years from previous careless owners.

95 NC 993

Many factors to consider but I'm mostly with rg588911 on this one. RUN, unless you want a project car.

ilko

I would also advise against purchasing the car unless you are looking for a car that you will keep for a long time. If you and the seller come up with a reasonable price and you complete the repairs you will have a solid car for many many years and miles. And that counts for something.

Chuck W.

For the right price, go for it. You have some engine work done on the car and know you have a fresh engine. If the seller is unwilling to come down in the price to cover a vast majority of the repairs, walk away. There are many fine 993s out there looking for new homes.

Spidey 993

+1

vjd3

At that mileage, in all likelihood, the exhaust valve guides are worn out by now. I'd be surprised if the car would pass emissions with a burned valve, was there a check engine light showing? Did the shop check for codes on the secondary air injection?

The car sounds like trouble, but as others have said, if you can buy it right, and you don't mind having it laid up and the (rather large) gamble that once they get it apart they won't find other hideously expensive problems, then go for it, assuming the title is clean, no accident history and cosmetically the car is an excellent example.

When I bought my 97, it was clean and all there cosmetically, but I knew it needed a clutch and had SAI issues, so I bought it at a substantial discount, laid it up for the winter at the shop and had the valve guides replaced, new clutch, 60k service and new suspension installed. The motor was perfectly fine aside from the worn guides (at 58k miles) and the car has run like a Swiss (German?) watch ever since. It was a good decision for me, because I could have spent much more on a car that didn't have obvious issues, and might have had to spend that extra money down the road anyway.

It's like anything else, when you run from one thing you usually run into another thing, so be dispassionate about the car, make sure the numbers work and that the shop you used both for the PPI and where you might actually do the work is a reputable place that knows what its doing.

One more note, get the car up in the air and spin the rear wheels by hand. The front wheels should turn slowly. If they don't, the viscous coupler in the AWD is shot, and that's another big expense. I had a C4 that had its little driveshaft to the front wheels snapped clean in half, probably from either the idiot PO spinning the car or dropping the clutch for dragstrip starts. Word to the wise. You won't be able to tell just driving the car, spin the rear wheels up in the air.

Quadcammer

Disagree:

The leakdown numbers on your vehicle are:

Cyl 1: 3%
Cyl 2: 5%
Cyl 3: 4%
Cyl 4: 7%
Cyl 5: 3%
Cyl 6: 2%

How did i know that?

NP993

If the car is otherwise in good condition and has been well-maintained, and the price reflects the engine & transmission work that needs to be done, go for it.

bavarian06

What are acceptable leakdown numbers?

PNogC2S

You could look at mechanical work on a 70K car as an opportunity. If (and that's a big IF) you can get the car for the right price and if the car is otherwise in nice shape (good paint, interior etc). You could end up with a very nice driver that has a rebuilt engine for the price of a nice driver w/o a rebuilt engine, when all is said and done.
When figuring what you can pay, you should look at cylinder base leaks + burnt valve + 70K miles = engine rebuild. Price in the rebuild (from a reputable shop) and a few other likely "while you are in there" items (fix trans leak, ign. wires, new clutch, etc) then make an offer...if the seller takes it, good. If not, walk away.
Having said all that, there are a lot of "ifs" here, so it's hard to say for sure w/o more info.

Falcondrivr

+1

vjd3

The rule of thumb on leakdown is that you want them all relatively close to one another ... Bruce Anderson used to say that a healthy 911 engine should be between 2-6 percent. Having one cylinder out from the others isn't a good sign, and one cylinder being waaay out from the others is bad news. Same deal on a compression test.

race911

11% leakage from a burned valve? I've pulled heads apart with 30+% leakage from a valve and they could have been reused.

I'd say this is a car that's been driven this way a long time, and can (absent smog check issues) be pretty much driven indefinitely as-is.

Do NOT want to overpay for it, though.