Engine Jumped Timing Diagnosis- 2000 Base
 

Concerns a PROJECT BOXSTER - Couldn’t resist buying a $700 Boxster that wouldn’t start, w/133k miles. Diagnosed by a Porsche Dealer, as cam 1 had jumped timing. NO KNOWN INFORMATION other than that, from the previous owner. Husband died and the wife picked it up from Porsche and sold it after sitting for a year or so.

I brought it home yesterday, washed it, cleaned it up, and put it up on a lift and started to dig in. No metallic particle or plastic piece in the oil sump ( very surprised), and the coolant was clear orange.

Let’s just get this out of the way.....not every engine issue is the IMS. I’m not saying that this isn’t IMS related, BUT, I am not one that chirps IMS as the cause for every issue.

1. What are causes to jump timing that don’t produce any plastic or metallic particles in oil sump or filter?

2. What diagnostic steps/tests would you do, to determine possible failure cause?

I can pull the engine, and am absolutely realistic about potential damage. I have no illusions that there is a real simple fix. But before pulling the engine, I thought I would get the brain trust involved and methodically eliminate causes, if possible.

I do not want to try and crank it over, with the starter.

I know I can buy a replacement engine and throw it in there.

Thanks!!

Upon a little closer inspection, I did find a couple of small, hard brown plastic pieces in the oil sump. I didn’t mention before, but someone may have either drained the oil or been into the bottom end before, because only a couple of quarts of oil came out.

Also, I hooked up a reader. The only code that popped up was P0336. Camshaft position sensor error.

I turned the engine over by hand, both side cam shafts rotate.

Worn cam chain tensioner pads. The brown bits are pieces off the pads.

If the chain gets loose enough it can skip a tooth. Try turning the engine manually and see if you can get the slots for the cam locking tool to line up. As far as I remember they should both be vertical at the same time. That should give you a clue.

I grabbed my endoscope, and tried to take some pictures of the pistons on Bank 1. Not too sure it shows me a whole lot. Maybe more experienced eyes can tell me something. I have a feeling that I can only see the center portion of each piston, and not the whole thing.

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My 01 base slipped timing at 89,000. IMS was fine. LN bought the motor said it was a stretched timing chain. I abused the motor it had about 30,000 stage one over revs.

First thing I would do is ignore what they've told you about the car. Do your own diagnostics.
IE: how do you know the cam has jumped? CHECK IT. easy enough to check your cam timing on this motor. Anker already pointed you in the right direction.

Be sure you're chasing the right problem, is all I'm saying.

Remember that it's quite possible that somebody already dumped the oil & changed the filter, so don't assume there either.



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Absolutely 100% agree. I didn’t get a lot of information. Just that it died while the daughter was driving (no specifics) and that the Porsche dealership diagnosed that the bank 1 timing was off. I received the report.

I locked the engine at TDC with the “special locking tool” and used my borescope to to take a couple of pictures. It would appear that Bank 1 is indeed off, a little. I didn’t have enough room to get the locking tool installed, it you can clearly see the exhaust cam is rotated counter clockwise a little bit, just before being completely vertical.

For some reason I can’t attach pictures via my IPad or IPhone. I’ll try later with my PC.

I agree. I had the same issue with mine, the chain pads wore out and one completely slipped out of the way and got the chain loose. Take a look at my show&tell thread, that may give you an idea how deeply you will have to dig into the engine. I think it`s possible to fix it without pulling the engine out, it`s not an easy job though with the engine in place.

I was able to upload the pictures of the timing of Bank 1 via my PC. I also pulled the spark plug from Bank 1, when I used the borescope to try and inspect the cylinders.http://986forum.com/forums/uploads02...1559064715.jpg
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Thanks. I am curious, when the chain pad slipped out of the way and the chain loosened, did it do damage to your engine? Did you get a CEL or anything?

I will search for your thread and check it out. Thanks for the feedback.

I bought the car as non-op, I`ve never seen it running. The valves clearly made contact with the pistons, but nothing broke or got damaged.

With a cam out of time (and you have visual evidence of that) I would want to check the valve train to make sure nothing was bent or damaged..:eek::eek your endoscope pictures may be showing some valve piston contact:confused:. hard to tell. Pistons look undamaged.

Yeah....thanks. I kind of suspected that, from the way it looks....BUT.....hopeful. I am in the process of pulling the transmission and then the engine. I will dig into the engine and see what the status is, and then post some more pictures.

It would be waaaaaay overly optimistic of me to hope that there wasn't any damage to the heads or the valves.

Sounds like we need to get that bad boy running!!!! I see you are in San Jose. I am in San Ramon!

Bronco
Please post pictures of what you find, myself as well as many others will be interested in what your follow up finds.
Good luck with it, you may get by with minor damage.

It`s entirely possible. You mentioned the crank can spin around freely.

Oh, great! Feel free to stop by if you wanna look into the engine in person before you pull it apart. Mine is still in bits and bolts...

Thanks! I have had the good fortune of being able to attend Jake Raby’s engine assembly class in Georgia. We started off by disassembling two engines and determing the cause of failure. We then assembled a complete engine, from the ground up over the next couple of days. Very cool class.

+ 1

Very cool indeed..!

Nice! What`s required to be able to attend?