Value of Compression Testing?

[92GPW]

I was talking with a dealer today about an S2000 they have for sale and asked if they had performed a compression test. He responded that on newer vehicles (he said about 1999 or newer) that if there was a compression problem with the engine that either it would fail emissions testing (I'm in CA) or that the engine would throw a code. Since it recently passed emissions and is not throwing any codes he said compression testing was not required (although he would do it for me if I insisted).

Thoughts on this? Is insisting to have compression testing overkill?

 

[Lude_2_NSX]

Its a grey area. Compression testing tells you the overall condition of the cylinder's ability to seal. If there is a bad cylinder, yes it is likely that a code will be thrown. This is true on just about any OBD car with misfire detection, but especially on newer OBD2 cars. But, this is only if you have a cylinder bad enough to cause this. You can have slightly high or low compression (out of spec), and possibly still run without a CEL.

In my opinion, it is a cheap and easy test to perform (especially on a 4-cyl), and its worth it to determine that all of the cylinders are close to each other in compression, and close to manufacturer spec. Its just cheap insurance. I can do a compression test on a OHC 4-cyl in like 15-30 minutes, and then I have a good feel for the condition of the motor.

 

[BATMANs]

Well, compression testing also can tell u if the rings are started to be worn out and this will help forecast ur plans for the car.