I'm new to the forums and hope that someone can help me out with a problem. I own a 99 GS-R, and am getting some strange missfiring problems. After I drive my car for about 10 minutes I get this strange lag in acceleration. I changed the spark plugs and fuel filter, but the problem still persists. I checked the compression in the cylinders and that is at 120 and only needs to be at 100, so thats fine as well. If anyone could give me any help I would appreciate it.

 

could be anything really. you check your ECU for codes?

 

No I havent checked the ECU Codes, I'll take a look tomorrow, thanks.

 

Sure. Only time that ever happened to me it was a bad O2 sensor but not necessarily the same for you especially since your car is quite new.

 

just making sure but you are running premium gas right?

 

yeah, I'm running premium gas. Its weird, because sometimes it runs really smooth. But as soon as i go into the higher rpm ranges it starts to run funny in the lower ranges. Also, the check engine light will come on if I let it idle for 10 to 15 minutes. But the next morning when I start it, the check engine light will be off.

 

Grab that code when the CEL is on...that is a wierd problem though.

 

once the CEL is activated, it should stay on until you clear the battery. If you pull code 71-74, that means the cylinders are misfiring (I'm still having that problem)...

 

I actually found out today that the compression in cylinders in the gsr should never drop below 135, and should be running standard at 270 psi, so I definnetly have a problem in that cylinder.