1997 Grand Am misses between 1500-2000 rpms

[tpmineweas]

My grand am is a 1997.it is the 2.4 "quad four" engine...no distributor or plug wires..anyway It misses between 1500-2000 rpm however it only happens when going up a hill. if you stomp on it it will climb the hill fine. In other words..it does not miss outside of that rpm range. at one point i did have a code that was Po300 and my buddy who teaches engine classes at a vocational school told me to change coils and the tower that houses the coils..i did..it ran fine for a week...then it went back to the same problem..and i changed the plugs the fuel filter the air filter..ran injection cleaner through it..i do not know what else to do..the engine light has not come back though so there is no code anymore..also it stalls and surges from time to time when at an idle..thanks for any inputs

[xeroinfinity]

Welcome to AF!

The p0300 a is random misfire. So you changed the coils, ICM and plugs, what about the boots that connect the plugs ?

If all that was taken care of its likely an injector issue clog or just worn out.
Test your injectors, if you use a noid light and they are all firing then test with an ohm meter acrossed the fuel injector contacts. Should be between 11-18ohms.

If that all checks out then its possible your PCM has a bad circuit.

I'd the fuel pressure too.

[tpmineweas]

yes I changed the boots that go over the plugs as well as the coils. So i should check the injectors next..correct?..I did put injector cleaner in..that wouldnt do the job??? of course if its worn out.. the cleaner wouldnt help..well anyway thanks for the input..much appreciated!