Check engine light but no codes?

[DLo]

I have a check engine light and I took it to my friend's shop. We tried to pull the codes but nothing came up. Light doesn't always stay on either, I thought it was because I took out the two smaller cats at first, but the O2 sensors are before the cats. I do have a pinging problem sometimes, the old marbles in a jar sound. I tried to clean out the MAF as posted before, but no help. Before I just randomly start replacing stuff, what else can I do to find out what's going on? I did a tune up last year, so I hope that's not the problem.

 

[urban96]

where are you plugging in to scan codes? on our cars you need to plug into the one in the engine bay. the one under the dash is useless on the GT as our cars are OBD1

 

[1TallMF]

+1

By "nothing came up" do you mean, nothing at all, or did you get the 111 system pass code?

 

[DLo]

I'm not sure actually what code I got, or if I got anything at all. I used a reader at my friend's shop, I think it was from MAC tools? Yes, I did plug it into the one in the engine bay. Should I get the reader from napa/kragens for 30-40 bucks with the wire extension?

 

[HISSIN50]

I'd just use a paperclip or test light.

Good luck.