engine problem, need help
 

Hi,

I just bought an 89 RX7 Convertible (non turbo) and it's got following problem:

car starts and idles fine, no problem there, however when you press on the gas pedal, engine stumbles and bucks repeatedly without actually dying--the problem becomes worse when going uphill, but when going downhill, you can press on the gas and there's no problem, car goes smooth.

I've replaced all fluids, spark plugs, fuel filter, catalytic converter, ecu.

Please help!!!

try a new fuel filter....$19.95 not too much even if it don't solve it...at least you could elimate that or fix it

Is the check eng light coming on? If the light is coming on, it might be in limp mode. A faulty metering oil pump can cause the car to go into limp mode.

yes, cel is on--it comes on and stays on only after you're driving and steps on the gas; if mop is bad, do I need to premix?

thanks,

was able to check CEL: 26, 27 and 30 (26-metering oil pump stepping motor, 27-metering oil pump, 30-air solenoid valve)

So, definitely seems like a blown MOP. Howeve, what is the code 30, air solenoid valve thingie? Would it cause my RX7 to lose power? thanks for all your help...

Also, to clarify, my car loses power as soon as I step on the gas: if I press more than a quarter inch on the gas pedal, engine starts to stumble and buck, whether going uphill or downhill...

Yep, you need a new OMP, and quite possibly a new ECU. Sometimes when the OMP goes, it takes the ECU with it. Its about a 50/50 occurance, however you can tell if your ECU was nuked along with the OMP by removing the top and bottom covers and inspecting for evidence of burning.

Disregard any other codes until you get the OMP one cleared.

im having pretty much the same problem but its getting better and i have an 89 turbo. it stumbles under a full load or in 5th gear. yah 5th is almost useless to me

mine stumbles in 3rd, 4th and 5th gear only--no hesitation/stumbling in 1st or 2nd gear, car pulls strong (redlines no problem) in those two gears. As I stated above, CEL codes 26, 27 and 30. Am still looking for a used/working MOP.