I have kind of an odd problem with my 98 accord thats hard to describe. 5spd transmission, engine (4cyl) has around 140k miles.

The engine starts fine every time, under any condition. However, the problem will only occur shortly after startup. The problem will almost never re-occur if its happened once and the engine remains running. However if I shut the engine down, then restart, it may happen again. Cold/hot/wet/dry/light/dark/bumpy/smooth, it doesn't matter.

The symptom:

The engine will not rev at times. The engine is not being limited (like a consistent rev limiter). I can floor it, and hear that the engine is loaded, but the rpms will not increase. If I pull to neutral immediately, I can freely rev the engine, and it will idle perfectly fine. It will do this for maybe 20-30 seconds, then all of a sudden the car drives normally. It almost feels like something is stuck or clogged, but I'm not sure where to start since the problem is so short/intermitent. If I floor it while this is happening, the car will start to jump/buck pretty hard, or the engine just loads up and the car will not accelerate.

Again, if I pull to neutral, the engine will rev freely. it kinda feels like someone is holding the brakes down hard, yet youre still trying to floor it. You can feel the engine load increase, but the car doesn't accelerate. Then all of a sudden it goes away.

I'm open to any suggestions/discussion as I'm not sure where to start. Thanks for the help!

 

I would start with the basics: fuel, air, and spark. Test your fuel pressure and do a spark test, as well.

 

Is the check engine light on? It kind of sounds like an O2 sensor problem or possibly a TP sensor issue. They are both know for those symptoms. What kind of test equipment do you have?

 

CEL is not on. No codes either.

test equipment - Multimeter

I thought about the TPS.... My first thought would be to drive with my meter hooked up and watch the voltage when it acts up... Only problem is if i shift to neutral, the engine revs like it should...

I can't see how it would be an 02 sensor. short term fuel trims couldn't have this much of an impact...

 

I doubt your multimeter will be "quick" enough to catch the TPS as it acts up but it's worth a shot. About the O2 sensor: what happens is the O2 spikes either rich or lean, usually lean (drops to near 0 volts) and in turn the PCM drives the injector pulse width substantially resulting in the "low power" condition. Vice-versa if the O2 spikes rich. Trust me it does happen. It's not extremely common but it's common enough.