I would sure appreciate some help with my 94Z... The car is 100% bone-stock with 85K Miles. No mods; everything is as-is from the factory. The problem: My car runs fine in open loop mode. However, after it warms-up (closed loop) I start to experience the following issues: 1) RPM surge when at a stop, and 2) Stuttering (cutting out) when I attempt to accelerate at speed (e.g., cruising at 40mph and hit the throttle). One other thing I've noticed is a fuel odor after I park it in the garage. The fact that it runs fine (excellent) in open loop, leads me to believe that the opti is good-to-go (I hope). One other thing, the car isn't throwing any codes (that I can tell); no dash lights. All of the hoses and sensor connections are good-to-go as well. My best guess is a bad O2 sensor. Any feedback/suggestions would be greatly appreciated.

 

You may want to check the coolant temp sensor and air temp sensor. IF they are ok, check the O@ sensors with a scanner & see if they are working properly (changing voltage at fast rate is good, steady voltage is bad). Change wires & plugs, and if still bad, it is probably Opti time.

 

Thanks Pete. I appreciate the feedback.

 

If the sensors that Pete suggested check out OK you could check the MAF signal and check the EGR for carbon buildup.