I have a 93' integra GS. The car is stumbling and shaking bad at idle. It sounds like it has a miss in it. But when you hold the revs the stumble goes away at about 3K and then is smooth. I would think if there was a miss it would just get worse with RPM's. but after that 3K it runs and sounds fine. Also at idle if you put your hand over the exhaust tip it is not a smooth exit. It exhaust gasses feel like it lopes like its got a big cam in it.(sorry hard to explain, its like blup..blup...blup) What's goin on with this thing.