1997 Honda Accord Help MAINSHAFT SPEED SENSOR
 

Hi guys,
Been looking at this forum for a while, there is a lot of good data on here.

I've owned a honda accord for a month or two. It's a 4 cylinder automatic 131,000 miles on it. The first few weeks it was working fine. All of a sudden it would shift at high RPMs (4000, 5000) it only happened a few times and it only happened when shifting into 2nd gear. It came up with a OBD-II error P0715 and some missfireing codes.

I cleared the code and the car worked fine, it wasn't shifting weird or anything. Then out of nowhere the car stopped shifting at all. It will sluggishly go into reverse. I've done some research to what the OBD code was and I found out that it is a MAINSHAFT SPEED SENSOR error. But I've also heard it a sure sign of the trany going completely bad. Also I'd like to mention that the car shakes a LOT when I'm stopped and in gear. When in park the car is not shaky at all. (My friend said it could be the engine mounts, which are shot) I have no other codes other than the missfireing.

My question is do you honestly think the trany is bad or do you think fixing the MAINSHAFT SPEED SENSOR will fix it and is that a DIY fix an mature can do? :confused:

Suggest downloading the 94-97 Accord emanual and checking the diagnostic for MSS faulty (obd1 code 15).

If MMS resistance is good at connector, then check again at ECM connector. If still good, the ECM may be the problem. We're beginning to see ECM faults in this generation of Accords more frequently.

No way to know if this predicts other trans faults. However, if ATF hasn't been changed suggest draining/replacing fluid at least once. If it looks especially nasty, a complete replacement is indicated (see youtube ).

good luck

What is mms resistance and ECM

MSS (mainshaf speed sensor) and ECU (Engine Control Unit). Sorry about typo.

good luck

I would say the tranny is going out. The 97 lx that I'm working on now had a bad tranny, main symptoms before it completely went out were high shifts and loss of power (tranny went out while I was on the gwb and luckily I was going fast enough to coast to the first exit lol, red lining was like 5mph)

Does anyone know where I can go to get a mainshaft speed sensor? I've been looking on line but I can't find anything. Its a 1997 Honda accord 2.2L L4 with a 4-Speed Automatic.

Did you go through the diagnostic procedure and confirm the sensor is open or shorted? These are reliable components and failures are rare, so fault could be damaged connector, wiring, or TCM fault.

Where to find? Suggest checking car-part.com for donor vehicles near your zip code, and calling for availability of part you need. It probably won't be listed under car-part.com as a listed item.

good luck

Also note that if "gunk" has built up on the end of the sensor it can cause problems with it reading correctly.....so it can't hurt to pull it and wipe off the end and see what happens ????

I believe this is part (Pickup, Main Assy - Part 15). It's $118 plus shipping for new, and a used part will likely be < $20, but more difficult to find/procure.

Honda Automotive Parts

PM's suggestion to clean and check sensor is a good one.

good luck

Did a 3x trans flush and the car started moving, it won't go into 2nd gear and is grinding really bad. also the trans fluid was a dark golden and smelt really bad. Looks like it's toast. No error codes so I know the slipping wasn't the sensor. Thanks for the help guys. At least now I know what's wrong with it. :)