My 92 civic suddenly started to run extremely rough while driving home the other day. When in park or neutral the engine idles and revs smooth and fine but as soon as its shifted to drive or reverse it begins to run very rough.

any ideas where to start? or what would cause this?

 

try a tranny flush that will tell you a lot and might fix your roughness

 

Can you explain how to do a tranny flush, mine is doing the same thing but have no idea how to do a flush. I have a d series tranny automatic. Thanks

 

The transmission fluid looks fine and the transmission actually shifts good. If the tranny itself was the problem why would it make the engine run horrible when just sitting there not driving? The engine is actually miss firing and running poorly when in drive. but like i said in neutral it idles fine, revs up great and sounds perfect. its only when its put into drive that it instantly starts running bad. rough running, cuts out, miss fires. I cant see the transmission itself being able to do that?