1988 XJ "missing" after gearbox change

[SuperRoo]

Hi all,

had the auto box of my 4.0 litre Laredo changed recently by my local garage:repair: . Upon its return to me it has developed - a) a knocking sound upon start up, which gradually disperses upon the engine warming up - b) it now runs rough and misses when accelerating or travelling above 25 miles.

When stationary in "Park" it will also miss if the accelerator is pressed. It's been back to these clowns but to no avail:sure: I've replaced the plugs, leads, cap, rotor. Could they have touched/damaged a sensor???

All thoughts/ideas/remedies greatly appreciated

[langer1]

I would check the CPS it is on the bell housing and reads notches on the flex plate. The knocking sound is because something is wrong with the flex plate and the torque converter.

Everythings going to have to come back out and they know it.

[SuperRoo]

Cheers mate,

if the cps is being affected by the flex plate then dropping the box and reinstalling should cure the cps signal too? (if nothing else is damaged!!!)

[langer1]

They could have left some bolts loose also.

[SuperRoo]

If it's "only" loose bolts!! Hopefully it won't be too serious. I'll be giving it to a Jeep specialist this time so hopefully he won't take the piss, NEVER EVER again to my local garage

[lawsoncl]

I'd crawl under there and look real good around the bellhousing and make sure they got all the bolts tight. You'll get these symptoms if the bellhousing is loose.

[YosemiteXJ]

My '88 has the exact same symptoms and they just started by themselves. I have changed the plugs, wires, cap, rotor, coil, have confirmed no vacuum leaks, checked the throttle position sensor, and spent $400 at a local hotshot shop who usually is the best on finding problems with sensors. They were unable to find the problem. It

They couldn't find the problem and thought it was somehow related to the torque convertor and sensors there.

Also, now I have NO POWER at all in reverse and it misses all of the time.

I am stumped.

Gary

[dirtymuddog]

im having the same problems, what got me is after replacing the cps, tps, coil, plugs, wires, cap, rotor, fuel pump/filter it ran great..for one night. then no start next morning..i just this am replaced the cpu, but no change..check your injectors i think thats my next step, cuz they arent gettin constant fire

[langer1]

A bad flexplate will cause all that. If the flexplate is wobbling the CPS will not get a signal and the injector will not be fired.

[87manche]

My '88 has the exact same symptoms and they just started by themselves. I have changed the plugs, wires, cap, rotor, coil, have confirmed no vacuum leaks, checked the throttle position sensor, and spent $400 at a local hotshot shop who usually is the best on finding problems with sensors. They were unable to find the problem. It

They couldn't find the problem and thought it was somehow related to the torque convertor and sensors there.

Also, now I have NO POWER at all in reverse and it misses all of the time.

I am stumped.

Gary
reverse is usually the first place a loose bellhousing/flexplate shows up,

[SuperRoo]

Still haven't sorted it out yet. I've been doing my winter prep's - just replaced the pads and discs, bled the system, new shocks and flushed the radiator, so hoping for no further trouble once she is back up and running. I'll be dropping her off next week to be looked at by another garage - fingers crossed :)

[POSXJGuy]

i would bring it back immediately and threaten to whoop ass. you paid for them to do it right, not to create problems.