I have a 96 5 speed maxima and 50/50 of the time when i let off the gas the car jerks as if there is detonation in the engine. I read alot about faulty knock sensors. This is the deal, soon after i bought it used the CEL light came on and i had to replace an oxygen sensor, knock sensor, and the EVAP canistor that collects sulfer deposits. I have read that the knock sensor could be causing this jerking by having a resistance that is just out of wack a bit, but not enough to turn on the CEL. Im lost as to what i should do about this jerking. Anybody have any other ideas about what it might be? Also if it is the knock sensor what should the resistance be? And if it is faulty do i have warrenty with nissan on the part? I installed it in January of this year.

 

Check and adjust your Throttle Position Sensor (TPS)

Clean your throttle body --> www.motorvate.ca

 

Oh ya i cleaned my throttle body yesterday. A little better but it still jerks.
TPS? dammit, how can i check it myself?
i dont want to go to nissan and have them tell me it will cost $200 CAD + install.

 

could also be worn engine/tranny mounts. my 93 Max se 5sp jerks cuz of the mounts.
Jae

 

The knock sensor wouldn't really effect when you're lifting off the gas, and I guess if it did, this wouldn't be the only place. If anything, the ECU will retard the timing due to readings from the KS (appropriately or inappropriately). With this in mind I think you'd notice if anything hesitation, or decreased power (than normal) in acceleration, especially at WOT.

Check mounts if you've been driving the 5-speed for a while and have noticed a change in the way it jerks when 'engine braking'.

 

mine does this too if im in first gear, but i made a post on that and from what i hear thats normal
the other gears don't jerk when i let off the gas.

 

yeah, jerking in first gear is normal if you abrubptly let off the accelerator.

 

Mine does that as well!
i thought it was normal..

****

well,
i do have 117k miles though..

so where do i begin to look?

it does this very often.. pretty sure it's not only in 1st gear..

 

It is completely normal for your car to jerky even violently if you let off the gas ubruptly in 1st, or even second gear. This plagues me every morning in rush hour traffic

 

If MAXSRB has been driving the 5-speed for a while, I'm sure he knows about this. But he may not. It takes a steady foot to keep the 5-speed max smooth in low speeds, especially in 1st and 2nd gear...you can't just lift off the gas pedal. Even feathering it lightly can be hard to do right - most of the time I'll anticipate jerking the car depending on the sitch and throw it into neutral for a few seconds, then double-clutch it back into the right gear for whatever accel I need.

The effects of engine braking and/or whatever else is going on that causes these natural symptoms in a manual tranny differ on inclines. Just have to get used to it. Quick neutral drops are my friend, but all that double-clutching may wear the clutch too much for some's tastes.

But if MAXSRB is aware of all this and it's really inappropriate jerking, it may be something else.

 

Well put. Yes i do know you need a steady foot and that even as steady as i can get it it still jerks once in a while. As for double clutching ya i do that too but only sometimes as i know it wears down my already worn down clutch. The problem of it jerking can be found in 3rd gear as well so i doubt its my driving abilities. Also in some cases when i let off the gas abrubtly it is absolutly fine and does not jerk what so ever. I have driven other 5 spds and have not had this problem unless im lazy and drop the clutch. On the maxima however i get jerkyness even at cruising speed when i let off a bit.
Is it my Throttle Position Sensor or what? How can i check if its my TPS?

 

Ill check my engine and tranny mounts ASAP. Thanks.

 

My car jerks too. I replaced my knock sensor a few months ago and my engine mounts a few months before that. I guess I should check my tranny mount and TPS next.

 

My car was doint the same thing almost and it was my MAF i replaced it with a used one from junkyard and car is running fine now.

 

Ok im almost sure its my engine mounts since i bought the maxima used with 142000 km on it. The only problem now is the cost of the damn mounts. Cattman has some "performance" mounts that are supposed to kiil wheelhop and my jerkyness too. But those mounts cost 300$ US. I was thinking that if i cant find any in the neighbourhood of 100$ that i could live with the jerkyness.
How much would a motor mount from nissan cost? Also i hear its not too hard to make my own mounts. Is making a motor mount a DIY project or is it like working on your brakes? Let someone who knows what they are doing do it.

 

I have this same problem. I'm pretty sure its the motor mounts.. I doubt its anything to do with the throttle body, etc. If I let off the pedal it gives a jolt/jerk and if I tap it and let off it will always do it. I'm also auto so its not the engine braking you get when you let off in low gear. It could posiibly be the tranny mounts.. maybe I should drive down the road with my hood up and do it and see if my engine moves noticeably.. my moms 98 also does this...

 

F**K!

Where does one get motor mounts for cheap?
How hard is it to replace them yourself?

 

calm down buddy.. lol.. I dont know the answer to your q's tho I wonder them myself.. If someone could confirm either motor mounts or tranny mounts that would help me out..

 

******* motor mounts are huge
i thought it was a DIY project
bs to that. I aint putting no homemade motor mounts in there
im just gonna try to shove some stuff in there and hope for the best.
All jokes aside im sick of the jerkyness, i am smooth when it comes to the clutch but i have tried alot of things. Spark Plugs, all sensors except TPS and cleaned out my TB. Ive rooted it down to the throttle position sensor and the motor mounts. Now which way to spend the money? so much for routine maintenence. I want a y-pipe dammit!