My car has a CEL for, p0035 crankshaft position sensor, and is running in limp mode. Took it to the dealership and they put a new one in, now with the new one in it doesnt start. Or at least it doesnt start with the sensor plugged in , on my dsm the car wont start without the crank sensor plugged in. The tec came back to me and said the car needs a new ecu because of this, and he pointed out a modifry yellow box. Although i was told the car was never modified looks like it might have had gears at one point. Could installing that yellow box wrong fry the ecu ? Anyone run into a similar problem ?

 

An improper YB install can surely damage the ECU. However, thay are easy to install and it is not likely. It it hooked up and operating? You should see a red light flashing inside it with the key on if it's working. If it's working, it did not cause the problem with the ecu.

Looks to me they are looking to point the finger at something so they don't have to cover it.

 

I had them remove it, so i dont know if it was working properly. Looks like its time for the wallet to take annother hit and buy a new ecu

 

Just look for one here on the board. People sell them all the time. If you can get one with a key, you can swap ECU's yourself without a trip to the dealer for key rewriting.

 

Swapped in a new ecu, same thing only starts with the crank sensor unplugged. Any other suggestions ?!

 

so it would start with the old sensor...but not the new sensor.

why don't you try using the old sensor???

i think i had that cel...i unplugged it and plugged it back in...i figure it was loose or dirty.

 

If the old one worked i wouldnt have any problems, im going to get another sensor, maybe i got a factory dud

 

The Crank sensor is a hall effect (2 wire) sensor.

So if the stock ECU and new ECU show the same results, then the problem has to be what is left. The wire harness. Also hte new sensor should have presented the same problem as the old sensor, assuming the sensors are both good and something else is bad.

Can you tell me where the Yellow Box was wired to? Wire colors? What connectors it was wired to? What else is a miss under that dash where the ECU is located?

Also I assume your car as work right fomr some amount of time and no changes were made to the car. It just threw the code? If so how long has the car worked right?

 

I had them take it out at the dealer, and i oln had a quick peak at it. I checked out the wireing diagram @ modifry and everything was reconnected correctly. I dont believe the YB is the culprit, ive had the car since march with no problems. Ill have honda test the wire harness

 

did you get this problem fixed?? i'm having the same issue....