Another thing which *may* throw a lean code is a very clogged fuel filter- do you know when the fuel filter, under the car, was last replaced? Was it installed in the proper orientation?

I was having similar problems on an S10 Chevrolet truck, the SES light, varying idle speeds- I thought it was a vacuum leak, but when I replaced the past-due fuel filter, everything cleared up- ran a lot better, too.

 

Thanks everyone for your help.
I cleaned the MAF yesterday and was amazed just how easy it was.
The car ran much better today, if the SES light goes off in the next few days and stays off then I know for sure it's fixed.
Shame I don't have a scanner to reset it and I am not paying the garage again.

 

You don't have to. Disconnect the battery, turn the key to "ON" for several seconds. Keep the battery disconnected for a few minutes. All codes should be erased.

P.S. I bet it's quite a trick driving that car around some of UK's narrow roadways.

 

I have been driving it for 8 years now and I have to admit it’s not the easiest car to drive in the UK but the looks, sound and raw power make it a pleasure especially in the summer with the roof panels out. On top of that my stock Z28 + Borla beats most European cars costing twice the price.
The only thing I hate is GM bought Daewoo a few years ago and put a Chevy badge on it, now we get cars like the Chevy Matiz with its 796cc engine. What happened to pride and pedigree?
Shame the problem with the warning light has not gone so I have ordered a PCV and Air intake sensor and I may be about to buy a used scanner from a very helpful guy up north who’s into drag racing

 

All fixed now,
I bought a scanner from a very helpful guy in Manchester (UK), then after more playing about, it turned out to be the short pipe from the PCV to throttle body, there was a split underneath where I could not see.
I sprayed WD40 arround the pipes and the idle speed went up, then I wrapped my fingers arround the pipe and found it, the best thing was that the hole was making a hissing noise and the garage said this noise was a warn Tensioner pulley assy, so thats saved me more £££
Thanks for all the help and advise guys.

 

Glad you got it figured out

Enjoy your car

 

Remember how I said to check the PCV system? Sometimes diagnosis must go beyond a simple visual inspection. Glad to see that it's running right