Its a 93 Honda Civic Si. Car starts up fine, but the engine (I don't know how to describe by typing) it surges,sputters, or putt-putts. I don't know what to call it. But anyways the engine shakes really crazy on idle and when you step on it, its even worser. It idles at 1500rpm from start up and after the engine warms up, the idle drops to around 1000rpm and never lower. The other crazy thing is that when you turn on the A/C the engine dies. But it'll crank right back up. We got this problem for while and we can't seem to solve it. Can you help us out?

 

Sounds like MAP or TPS problem, or vacuum leak.

Any codes?

 

Yeah, what is the last thing you did to the car, maybe that is your problem. You do a timing belt or mess with the firing order? Like poison said, any codes?

 

Well my friend just bought the car for about 3 months and he did nothing to it yet, but just add a new radio thats it. Everything in the engine bay was untouched.

 

maybe he is running 12v into the chassis, and messing up refrence ground, dunno...

Pull the radio out, see what happens, see if the timing jumped a tooth too.

-PHiZ

 

Ok, I'll check those suggestions out. Anybody else got more suggestion on this problem?

 

check ur timing.