first off, no im not hitting my rev limit at 4k RPM.

ive been having issues with my engine lately. the first batch was solved with a primary 02 sensor as opposed to changing both 02 sensors and cleaning this and that for $800 like my mechanic wanted. i was throwing misfire codes and catalyst below threshold codes.

so i changed the 02 sensor and things were going fine. 3 weeks later ive got a new problem, and the code i got was P0335 - "Crankshaft Position Sensor A Circuit Malfunction". every once and a while my car acts up randomly drops about 500 RPM for a split second, jolting the car. othertimes it acts like there's a rev limiter, usually around 4000 RPM. there is no pattern according to when it happens (ie: weather, engine temp). im completely lost and need help!

i really dont want to take it to a mechanic either... im not that rich

edit: its a 2001 5 speed / 1.7 litre sohc vtec

 

It sounds like you have a problem in the crankshaft position sensor (or circuit) from the description of the code. It seems like everyone once in a while your computer is getting a BS reading from teh CPS. Since you have an intermitten problem it will be tricky to diagnose especially since you don't know the conditions under which the problem occurs. If you can recreate the problem on command it will be really help in diagnosis. Anyway, i would start by tracing the wires from the CPS back to the wherever it is they go (prolly the PCM). THis problem could be caused by a problem in the wiring (loose/broken connection). You don't want to change the CPS sensor (which isn't gonna be cheap) to find out it is still broken. So first look for loose/broken connections or broken wires. A wiring problem will send false readings to the computer which will cause your engine to do wierd things. If you are positive that the wiring is not the problem, then i would say that your sensor is malfunctioning.

 

this may be a stupid question, but what does PCM stand for?
thanks for all ur help

 

PCM= Powertrain Control Module. Pretty much the computer that controls the engine. I tend to use alot of abbreviations

 

If it is the CPS, I actually have to add one to my car, the sensor itself is about $100, but unless your handy with mechanics its a bit of a pain toget to. Its located on the oil pump. I mean the parts are cheap but labor is a mother. You have to take off all the accesory belts and everything to get the Timing belt cover off to get to the oil pump and CPS. The sensor is held in by two bolts though and once you get to it , it shouldn't be too big of an issue. Big up a haynes manual and see if you have the audacvity to do it yourself

 

interesting - thanxs for the post and to Agent for his post.
some kind of engineering

thought they were off of the flywheel (or maybe some are).
here is a look at one such (not honda)
http://www.v8sho.com/SHO/CrankshaftP...sorRemoval.htm


http://experts.about.com/q/Nissan-Re...alfunction.htm

and autozone (91 - 98)

http://tinyurl.com/pql7w

 

Who engineered what?

 

i've seen some where the cps was below the starter.
have to get under the vehicle, but less to remove to get to.
(think it was a dodge)