Engine sputter on my NA

[Nickoli]

All the sudden today, my engine on my 93 NA started to sputter when I press the gas pedal completely down. (Sounds like the engine is running on only 4 cyls.) If I accelerate without pressing the gas pedal more than halfway, the engine seems to run fine. I ran an ECU diag. and got the infamous code 34 (det. sensor). All of the det. sensor wiring looks fine from what I can see and is outputing the correct voltage. If I let the car sit for a while, I get a code 55 on the ECU until I start it up and it goes back to code 34. Any suggestions, ideas would be great. Thanks.

[MikeMan]

It could be doing this for a number of reasons. If its only happening when you jump on the pedal it could be:

1) Sparkies. Check these for crud, and that they have the right gap. Easiest problem to fix so might as well start with it.

2) Could be the PRVR solenoid acting up causing the fuel pressure to be too high (flooding the engine)

3) could be the fuel temp sensor giving a false reading, causing it to flood/lean out.

4) could be the fuel pressure regulator causing it to flood/lean out.

5) could be the MAF sensor giving a false reading causing it to flood/lean out.

6) could be the throttle position sensor acting up.

7) Oxygen sensor(s) acting up.

8) Corrupted fuel timing maps in the ecu.

Sometimes these can screw up without the ecu realising. They can all cause this problem too.

You can narrow it down a little by checking the oxygen sensors (if they both read the same then assume that they are both ok)
If they're reading fine at idle then its most likely not a problem with the fuel delivery, and more likely a problem with the ecu maps.

-Mike

[freakonaleash1187]

it does sound most likely have to do something with your fuel/air mixture.

9) might be fuel injectors, one or two or more could be clogged just enough where they feed fuel at low rpms but can't meet the demand of higher rpm's

p.s. just a little nitpick, the z has platinum tipped spark plugs (if you don't, then your car shouldn't be running good) and platinum tipped spark plugs don't need there gap ever adjusted.