transmission jolt related to knock sensor or just jatco??

Post by **dirtrider5001** » Sat Nov 10, 2012 9:49 am

seems like every jatco ive ever had had a jolt at low rpm between first and second gear. my 98 pathfinder seems to be no exception. i changed the fluid twice second time pulling the pan and putting in nissan matic d. yesterday i thought it had went away completly(when showing a friend the jolt) then noticed it as i was leaving going down a hill in a traffic jam. I gotta fix the knock sensor but thats the only code. I sware i hear something loose in the trany when i just quickly gas it while driving faster than 30. the trans mount isnt metal to metal, And this doesnt just happen when the trans is cold, its all the time really. just wondering if anyone has figured this one out. I see how the knock sensor can cause this but is this really the issue??

Post by **zach7685** » Sat Nov 10, 2012 10:29 am

Could be the Trailing arm bushings.

Post by **Towncivilian** » Sat Nov 10, 2012 11:14 am

This is pretty characteristic of the RE4R01A transmission. If you're using Matic-D fluid, there's really nothing else you can do. You can try cleaning your MAF sensor, I've read anecdotes saying that cleaning it helped somewhat. Also adjust accelerator and cruise wires - see FE-3 and EL-161 respectively for instructions.

Check the resistance of your knock sensor to verify it's bad - see page EC-263 of the factory service manual for resistance values.

Post by **dirtrider5001** » Sat Nov 10, 2012 6:14 pm

well well well u wont believe it. This only happens when the trans is COLD. ive only been driving this thing for a cuple days since i bought it. It takes quite a while for that trans to warm up. If you shut the car off at full operating temp and leave it sit for say 10 min and then start it again the trans will already be cold again. It actually shifts really good when the trans is warm. frekin amazing. I had read post that said it does this when cold but i just figured i had it warmed up enough. I bought this thing and thought i was keeping it so i did a time belt/tensioner, waterpump, ect, but then i read all this crap about the strut towers and frankly it does scare me a bit. i mean anything can be fixed or prevented but its like if i wanted something built to car standards i shud just get a car. plus i really need the extra doe so im reluctantly selling, next will be frontier sc. Anyone else have horrible gas mileage when thier knock sensor went bad?? ill resistance check it but i know its bad from the code. i kno i can mount the new one on intake and splice into wires, according to u tube. Oh and whats up with the intermittant dash failure where all the guages go out and dont work again till car cools down.??? What else mite have tricked me about the trans is that the dash fails when the car warms up, which also triggers a vss code which may cud possibly cause hard shifting even when warm. Dash didnt fail today and it shifted smooth when warm so i think thats all it was
Sorry for the long post thanks so much for the help guys!!

Post by **Towncivilian** » Sat Nov 10, 2012 6:37 pm

It is normal for a transmission to shift oddly with cold fluid since the fluid is not at operating temperature and viscosity yet.

Spontaneously dying instrument cluster sounds like a bad ground somewhere. I would make sure all screws on the backside of the instrument cluster are tight.

If you live in a non-salt state or your Pathfinder is from a non-salt state you should have nothing to worry about. If you live in a salt state and the dealer inspects your Pathfinder and it passes the recall, you shouldn't have to worry about anything.