My check engine light came on a few days and I did the diagnostic joint I got from this website and the result was 2 problems: knock sensor and vehicle speed sensor. Now this may have resulted from a high speed meeting with the median at 40 mph bc of a high speed chase a few weeks ago.(long story dont ask) Anyways have any of you had any experience with either of these problems? and if so have they definately needed to be replaced(if so how much) or is it possibly a loose connection mechanically or electronically. I have rounded up a multimeter but I cant really tell what is what. Thanks guys
james

 

reset it.. take two asprin..

and call me if it comes back...

http://vbxmaxima.8m.com/ecu.html








-The Robot

 

bump

 

so you don't believe me? hmm.. ok

 

listen to spritemax young grasshoppa, he knows everything. It would be very wise to listen to him.

 

Ive had my ECU trip the Knock Sensor and I reset it and it's never come back. The Knock Sensor doesnt affect the driveability of the car but I have no idea what's up with the speed sensor. The only time Ive seen that trip is after when some people disable their speed limiter.

 

there was some kinda surge or somethin that trips that MIL.. I just read it last week.

 

The only time I ever get a knock sensor code is at the track, and only after running hard for a while. I just reset it and doesn't come back until the next track session. Follow what Sprint said (I think this is three replies that way) and reset thing and see if it comes back. If it does, repost and we'll try to figure it out, but I'm betting it won't.

 

Allright, Its not that I didnt believe you, I thought you were kidding.
How does that ecu sensor work, does it periodically run tests to see what is wrong? The fact that I had 2 errors is what is making me wonder. I mean if somehting is DEFINATELY wrong and u reset the ecu, will the check engine light for sure come back on?

 

Just reset the ecu and see if the codes come back. It doesn't cost a dime and it's a cheap diagnostic procedure. What could it hurt? If it comes back, you are still in the same situation.

Note: at least for the 3-gens, this is true. the ecu will keep the code in memory. If it sees 50 turns of the ignition key w/o seeing the code again, it will erase it from memory. If it sees it again, of course the light will stay on.

 

The Maxima ECU uses two trip detection logic. If a problem is detected on two consecutive trips the check engine light will come back on. So there is no harm resetting the light, because a real problem will turn the light back on again, confirming that there is indeed a problem.