I was thinking i needed a new motor for this 93 twin turbo Rx7 im Buying from a friend "a car dealer" but i find out it could just be a clogged front cat.. Some Input would be appreciated very much. The car has 96k on it and is bone stock. To my knowledge nothing has been replaced or messed with. My friend was going to fit it and resell it but i talked him into selling it to me Anyways when He got the car it wouldnt start at all. We put new plugs in it and it fired right up and ran pretty good but made some goofy spuddering noises like it was missing. It was real boggy in low rpms but seemed to run alright around 4000 or 5000 and up. The longer the car ran the worse the boggyness got on till it started smoking pretty bad and died. I was going to try taking the cat off tomorrow, punching it out reinstalling it crossing my fingers and turn the key. Anyone here have any thoughts on this matter or had the same problem?? Thank you- Joe

 

There is a Pre-cat and a Cat on this car so you would have to see if either one is clogged. If its 96k miles on the stock engine then it is possible there is something wrong with the engine. I would be prepared to spend the cash for another engine soon either way.

 

Clogged cats tend to reduce boost and power at higher RPMs, not low RPMs. So I think something else is the problem. If it has a stock front cat you should punch it out or replace it regardless.

I think you might need to do a compression test first, then if that's ok check the TPS settings.