I bought a used 2000 Z28 about 2 weeks ago. Took it in the be serviced because of service vehicle light and tranny grinding.

They told me that the reason my service vehicle light was on is because the previous owner has a larger throttle body on the car which is causing it to run lean? I'm not sure if this is right because I'm not that knowlegdeable yet.

I also had some tapping and they told me that it was because I was running cheap gas. Is the possible, or are they just trying to keep from doing some actual work?

What do you guys think?

 

I haven't heard of a code being set by a bigger T/B, but I think I have from an aftermarket MAF (I could be wrong though).
If the engine light just now came on after 2 weeks, and they're blaming it on the previous owner..............I think they're full of it.

If when you say "tapping" you actually mean detonation or pinging, then yeah, the first thing I would do is put in higher octane gas (which you should be doing anyway ). If they are blaming a mechanical tapping on lower octane gas, then I'd call again.

 

Thanks...

Well.. the SES light goes on and off. The mechanic that called me said that the throttle body had been made larger. He didn't mention the MAF, but I guess thats what is really the problem.

About the pinging, I had no clue that these engines were that picky about gas. So I guess when I get it back I'll be adding some octane booster and bumping it up to 91 or 92 octane.

Thanks for the info.

 

Do not run octane booster.

Just run 91 or better octane. 93 if you can get it in your area. You should be running premium.