automatic transmission acting like it is remaining in lock-up when stopping at stop sign

[i need help & guidance]

 

 feels as though i am trying to stop at stop sign in a manual transmission and have left the transmission in gear. bogs engine down

 

  the truck has been working great for last couple of months 

and now when i come to stop , trams  places load on engine and stalls engine if i stop too hard

 

and it feel like if you just let it idle and took foot off the brake.  it would just move along like it does not want you to stop the truck.

 

  so i am thinking auto transmission is staying partially in lock up.

 

fluid level is checked and is correct.

 

  do i need to do a service of transmission or check and see if transmission bell housing has come lose

 

or what ever suggestions anyone has..

 

 

[85"720]

1 hour ago, i need help & guidance said:

 

 feels as though i am trying to stop at stop sign in a manual transmission and have left the transmission in gear. bogs engine down

 

  the truck has been working great for last couple of months 

and now when i come to stop , trams  places load on engine and stalls engine if i stop too hard

 

and it feel like if you just let it idle and took foot off the brake.  it would just move along like it does not want you to stop the truck.

 

  so i am thinking auto transmission is staying partially in lock up.

 

fluid level is checked and is correct.

 

  do i need to do a service of transmission or check and see if transmission bell housing has come lose

 

or what ever suggestions anyone has..

 

 

 How Is your idle speed in gear?? Is is high?  Fast idle cam can get stuck and make the truck want to take off on it's own with no input  from  the  gas pedal. 

[i need help & guidance]

i cant help but feel this issue is related to erratic and some times higher than normal idle. 

 

is it possible for these trucks to burn up the fuel pump

 

if truck runs out of gas and you leave key on and coast down the road to a gas station ? ..

[datzenmike]

I think the locking torque converter was introduced half way through the '82 model year so is built before Nov '82 you probably don't have it.

 

There normally is some drive when in gear but the characteristics of fluid coupling at low speeds allows a lot of slip. Only when revved up does it couple more firmly. I would look at the engine idle speed.

 

When you are idling in gear at the lights and you slip it into neutral does the engine rev up?

 

Try pulling up to a stop using the hand brake. Any difference?

[i need help & guidance]

i had to turn idle up because the engine dies if i reduce the idle down to normal.

 

if i move from drive to neutral at stop sign... the rpm goes   way up.

 

 i took the carb off today and fixed the high idle cam thing . the spring had fallen off

 

 i ordered a transmission gasket today and will change atf fluid out Thursday when gasket comes in

 

parts store said there was no trans filter or anything available to replace when pan is dropped ...is this true ?

 

any suggestion or help regarding the fluid change would be great.

 

thank you.

 

 

[Draker]

Get the engine run in right first. Sounds like carb issue at idle and your compensating by adjusting for it.

[85"720]

15 minutes ago, Draker said:

Get the engine run in right first. Sounds like carb issue at idle and your compensating by adjusting for it.

This^^. 

[Charlie69]

Check for vacuum leak.

[datzenmike]

7 hours ago, i need help & guidance said:

i had to turn idle up because the engine dies if i reduce the idle down to normal.

 

if i move from drive to neutral at stop sign... the rpm goes   way up.

 

 i took the carb off today and fixed the high idle cam thing . the spring had fallen off

 

 i ordered a transmission gasket today and will change atf fluid out Thursday when gasket comes in

 

parts store said there was no trans filter or anything available to replace when pan is dropped ...is this true ?

 

any suggestion or help regarding the fluid change would be great.

 

thank you.

 

 

 

Not true, maybe they just don't have one. The Nissan 3N71B has a transmission filter, keep trying. Maybe the dealer? or a transmission repair shop? The torque converter will still have old ATF in it. After re-filling with new ATF before starting disconnect the return coolant line and idle long enough to pump out about a quart of fluid and shut off. Top up the transmission and repeat. The new ATF will flush out the old. This is not perfect but will certainly dilute the old ATF in the converter without allowing it back into the oil pan. A couple of quarts will do. Re-check the transmission level when level and warm.  Make sure it is NOT over filled. Use DEXRON ATF

 

Spray the rear of the carb liberally with WD-40 and move all the linkages to clean and lubricate them.

 

Definitely look for vacuum leaks first, then...

 

On a thoroughly warmed engine....Turn the idle speed as low as possible. Turn the idle mixture screw in and out slowly to find the best smoothest idle speed. Presumably the idle increased so turn it back down and repeat the mixture adjustment again. Keep going back and forth until the idle can not be improved and the idle speed is about 700-800 RPMs. This will give the best strong idle when in gear.

 

 

[i need help & guidance]

how do i know which of the trans cooler lines is return ? 

 

   the trucks starts and runs and idles fine . 

 

* only when i shift truck in to drive or reverse  the trans is not coming out gear far enough ,, to take load off engine. so it dies when idle is set to specs 

 so i had to turn up idle to get engine to stay running .

and have to shift to neutral when stopping at stop sign , where idle escalates

 

   when engine is in neutral

i can turn idle way down to like 600 and it runs , idles smooth .. ...

 

the choke and high idle work fine too,, when first starting

. i had to replace new alternator the other day cause bearing went out.

so that too is fixed and no more squealing belts at start up.

 

   i cant thank everyone enough for helping me.

 

  i will have fluid change soon and post update

[datzenmike]

Take either of the lines off the bottom rad cooler. ATF will pump out of the line or out of the rad. The difference is about 6" of tube inside, no big deal. I think it's the line on the driver's side but whichever is easier.

 

Engines can idle properly at 600 but not be able to bear any load, even an automatic. Idle should be more like 700-750 when in gear. A strong idle with correct timing, valves set and mixture and idle set is the best.

[Charlie69]

Here.

 

https://www.rockauto.com/en/catalog/nissan,1982,720+pickup,2.2l+l4,1210239,transmission-automatic,filter,8600

 

[i need help & guidance]

this is as far as a i got today. 

 

i took cooler lines off

 

and used air compressor to blow out fluid from radiator and both hard cooling lines going back to transmission

 

 

here is as a far as a i got today .

Edited January 31, 2019 by i need help & guidance