I just wanted to run this by some of the pro's here and see if its just me or im experiencing some kinda problem with a/f. I recently got my car back from Rotary Reliability after having a massive vacuum leak, and everything was running fine. They told me to replace my plugs (autolites) with NGKs as soon as I get a chance too and I did. It seems like power drops slowly after 5k though, im not sure why but It doesnt feel the same. Replacing the fuel filter is next on my to do list but do you guys think it may have something to do with lack of air or fuel?? Or the exhaust being clogged? Only exhaust mod I have now is CS cat. back and thats cause the old exhaust was literally falling apart, it was a giant piece of rust. Could that indicate the condition of the cats also? I find myself shifting in the 4k region to keep up with traffic. Thanks for any feedback.

 

It's entirely possible your stock cat is plugged up. The symptoms seem to match.

 

Thanks for the tip. Ive been considering it too. When I had the exhaust off the main cat didnt look clogged, could it be the pre cat?? Any chance the fuel filter might be involved in the problem?

 

What year RX-7 is it? And model with how many miles?

Autolites? I have never seen that plug. What do they look like?

 

Its an 87 NA with 105k miles. The autolite plugs all the look the same (no diff between L & T) and dont have that platform around the electrode like the NGKs

 

btw- the air pumps been removed for about 3 or 4 months now. Im guessing this sounds like a definite clogged cat? RB race pipe now?

 

Yeah dude i am 98% sure that it sounds like you cat(s) are clogged. I had the same problem as well and when i went ahead and gutted them, it solved the problem. Now i have loud exhaust though