I have a 1994 Chevy S-10 2.2L that idles fine and revs fine when out of gear, but when you give it more than 50% throttle under load it bogs and won't accelerate any faster. The only problem code showing is 12. So far I have replaced the air filter, fuel filter, fuel pump & screen, IAT sensor, TPS, O2 sensor, spark plugs, cat, and muffler. The only other thing I can think of is possibly the MAP sensor, but there are no problem codes. Maybe the new fuel pump was bad.
God I hope not. Anybody else ever had a similar problem?
Thanks for any advice at all!