Hey guys,

I'm not a very technical person, but I'm going to describe my situation as best as possible.

I got a CEL on my car, and after a few days I got around to taking it into a shop. I'm expecting it to be a relatively small issue, but when I call in to check, they tell me that 3rd cylinder is running with low compression. The cylinder head is also pretty wrecked, along with the "guide." The car is not running lean in one of the cylinders. The coloration on the headers was the same across all 4.

The mechanic I talked to told me that I shouldnt have any of these issues with the mileage on the car. He said that the problems are something he would expect to see on a car that has had the rev limiter removed, and has been abused/raced.

Before I purchased the car there was a supercharger on for a period of time. The seller said that it was on for under 5000 miles, but idk if he was truthful or not. I have owned the car for two years, no CEL before now, no issues with the car to speak of up to this point. I have done some autocrossing in the car, but nothing too intense. Oil has always been changed regularly, and the car has run great up to this point.

One of the things I discussed with the mechanic was the possibility that one of the previous owners switched out the engine in the car with an engine that had higher mileage. How would we verify that the engine in the car is the same one from the factory? (Basically, where can i find the VIN on the engine?)

What else do you think could be the cause of these issues? I'm really at a loss here.

Thanks in advance
CPL

 

You can find the vin on the block under the intake mani

 

What does the CEL say?

 

what is the CEL code? My guess is that you dropped or bent a valve from a previous misshift based from what you and your mechanic are reporting. The s2k has been known to be able to take a misshift but it wouldnt be a problem till thousands of miles later when the retainer finally fails. The car will run perfectly fine on a cracked retainer, it is when that cracked retainer finally fails and drops that valve into the cylinder is when the consequences occur. A trashed head and a ruined valve guide are all signs of a failed retainer. I believe you can find a VIN number on the back of the motor on the cylinder head. I believe it is stamped in a green piece of metal, but in order to see that you need to pull the motor or get a mirror back there somehow. Did you hear any grinding noises when the CEL occurred? Did you feel a loss in power? How was the car idling afterwards?

Some cracked retainer info
https://www.s2ki.com/s2000/topic/847...lve-retainers/

pic courtesy of Billman250



partially cracked retainer, note the owner reported that the car ran perfectly fine even on these cracked retainers.

 

that is not the VIN, that is the engine serial number.