1990 ranger jerks when decelerating

[kody28540]

It's done it for a long time so I just wanted to see if I could get some feed back I've just about replaced every emission part on my truck and all other sensors. When I decelerate at coast like stoping at a stop light truck likes to jerk but stops when clutch is engaged also trucks rpms like to fluctuate all the time mainly too high of rpms it likes to run at around 11 to 1200 rpms then it will drop down to normal then go right back up

 

[doorgunner]

Does the engine light come on?

Have you checked for any trouble codes on the vehicle computer?

 

[kody28540]

Yes I have it says the egr valve or evp sensor is in-op but I replaced both of them in the past and the check engine light will only come on when accelerating but goes off as u left off the pedal

 

[dukeman2251]

I amhaving the exact same problem and have replaced almost every possible thing as well if someone knew the answer to this it would be awesome. Do you notice a little bit off a loss in power when climbing a hill then it suddenly will come back without even moving the gas pedal? its not huge but i can feel it happen sometimes.

 

[kody28540]

I'm not really sure about the loss of power bc where I live now there are no hills..lol...but I've had the jerking problem as long as I can remember I would love to know why...is ur truck saying ur egr valve or evp is in-op also?

 

[dukeman2251]

Yea its code 31 or 33 or something like that and ive replaced those. The only other thing i can think of is the egr valve solenoid on the passenger fender but i e tried everywhere and they are not being produced anymore from what i can find. Im getting the up and down idle alot toat stop lights too.

 

[wildbill23c]

Take your vacuum line off your EGR valve and plug it, then drive the truck and see if the problem has gone away. If the problem no longer exists without vacuum to the EGR then your EGR valve is bad. I had the bucking problem jerking problem, lurching, etc. after I disconnected the vacuum line to the EGR valve the problem went away.