1990 2.9 help , PLEASE!! Willing to pay for info!!

[Psychopathic]

I have a 1990 ford ranger 2.9 , 2wd ,automatic, completely rebuilt motor, top to bottom, got my tag and insurance yesterday, drove to work today, on i95, maybe 20 miles , drove back from work. Once on the off ramp and came to a stop, light turned green, " til this point it ran perfect" I gave it gas and the torque converter didn't engage, slowly engaged once rpm raised. From there on it wouldnt go over 15 mph, I'd let off the gas and the rpm would remain the same. The truck won't go in reverse , won't in first , second. Only engages in overdrive, after about 10 seconds in gear. , I changed the PCM , ICV , o2 sensor. Trans fluid is perfect, motor runs good, I have a feeling the TPS is faulty, when I bought the truck the wire harness had been cut and replace with another clip, not sure if the wire are in correct position, the wire are green, orange , black. Any info on this issue , " the torque converter issue and the wire color/position " please I need information soon ! I need my truck for work! Please guys

 

[LIMA BEAN]

Could be the vacume line to the modulator or the modulator itself.

 

[Psychopathic]

Hmm

Ok , I thought the modulator was only on older automatic trans?

 

[LIMA BEAN]

Ok , I thought the modulator was only on older automatic trans?

A4LD has one.

 

[Psychopathic]

Ok

An this is the transmission which is in a 1990 ranger 2.9 ? I haven't messed with the trans at all

 

[Psychopathic]

more info

and this would solve the torque converter problem? i can feel it wants to catch but it doesnt,, gets to 15-20 mph, maybe , doesnt shift, nothing , hits a certain point and then just revs motor up without gaining speed, no reverse, first, second.

i also have a problem at idle, the motor will crank and idle fine, but the rpm go from 900-1100 up and down, the timing is set dead nuts, new plugs /wires, new cam, professional adjustment valvetrain, new fuel pump , filter, iam running out of options, i have tried 2 TPS and both do the same thing. all clean new fuel, clean fuel tank, new cam , lifters, cam bearings, crank, rod and main bearings, all seals, gaskets, everything is new,

this is starting to look like a electrical problem to me, i read that the TPS can mess with motor and trans , but i tried 2x tps. but then again the plug/harness has been messed with before i got this truck, i would like to see a picture of the stock plug and wiring from someone elses truck if possible, so i can make sure that my wires are correct.

the trans was a refab'd trans for a local company , the recipit was still in the truck when i bought. alittle over a year old. this is just very aggrevating. i love this truck , it is my favorite truck on the road.

PLEASE GUYS MORE OPINIONS!!! WHOEVER FIND THE SOLUTION TO THIS PROBLEM WILL BE GREATLY REWARDED!!!

 

[JRanger91]

This is just a shot in the dark, but my 1990 4.0l with a4ld had a somewhat similar issue. It wouldn't shift into all of the gears, found the vacuum line coming off the manifold that runs to the top of the tranny had become disconnected. I didn't have engagement issues though, so it's not likely your problem. Sounds more like a modulator issue.

 

[adsm08]

First things first. The A4LD IS an older transmission. It's a design that hasn't been in production for almost 20 years and is 30 years old. It is also the only auto trans that ever came behind the 2.9 from the factory.

I agree with the initial assessment that the issue is very likely to be in or around the vacuum modulator. Your symptoms are consistent with incorrect throttle valve input and/or extremely low fluid. A common point of failure on these transmissions is the vacuum modulator. The diaphragm will rupture and do two things. First it kills the throttle valve input to the trans. Second it sucks all the fluid up into the intake of the engine and burns it off. This creates a rapid fluid loss with no apparent external leaks.

The first thing I would do is crawl under, pop the vac line off the back of the trans, and not have my face under it in the likely even that fluid comes running out.

 

[Psychopathic]

First things first. The A4LD IS an older transmission. It's a design that hasn't been in production for almost 20 years and is 30 years old. It is also the only auto trans that ever came behind the 2.9 from the factory.

I agree with the initial assessment that the issue is very likely to be in or around the vacuum modulator. Your symptoms are consistent with incorrect throttle valve input and/or extremely low fluid. A common point of failure on these transmissions is the vacuum modulator. The diaphragm will rupture and do two things. First it kills the throttle valve input to the trans. Second it sucks all the fluid up into the intake of the engine and burns it off. This creates a rapid fluid loss with no apparent external leaks.

The first thing I would do is crawl under, pop the vac line off the back of the trans, and not have my face under it in the likely even that fluid comes running out.

Thanks Man Will Try In The Morning!! Thanks Alot,

In Search Of More Opinions Still ,Everything Helps

 

[70roadrunner]

if that's not the problem, it is a more serious problem. the part that makes me think this is the "no reverse" symptom. I hope that ADSM is right, not me!

 

[LIMA BEAN]

if that's not the problem, it is a more serious problem. the part that makes me think this is the "no reverse" symptom. I hope that ADSM is right, not me!

Because no 1st and reverse is what made me think modulator or vac line. Let's hope for the best.

 

[Psychopathic]

First things first. The A4LD IS an older transmission. It's a design that hasn't been in production for almost 20 years and is 30 years old. It is also the only auto trans that ever came behind the 2.9 from the factory.

I agree with the initial assessment that the issue is very likely to be in or around the vacuum modulator. Your symptoms are consistent with incorrect throttle valve input and/or extremely low fluid. A common point of failure on these transmissions is the vacuum modulator. The diaphragm will rupture and do two things. First it kills the throttle valve input to the trans. Second it sucks all the fluid up into the intake of the engine and burns it off. This creates a rapid fluid loss with no apparent external leaks.

The first thing I would do is crawl under, pop the vac line off the back of the trans, and not have my face under it in the likely even that fluid comes running out.

6am this morning , crawled under the truck , pulled the vacuum line off the trans, nothing, not a drop of fluid. Check the vacuum line in the engine compartment. Everything is connected and has a tight fit.

Started the truck, it went into reverse! Backed down my driveway, nothing! No overdrive, 1st, 2nd, nothing. Left it idling in OD for 10-15 seconds and it finally engaged the torque converter enough to get back in my driveway, at 2.5-3 k rpm and barely made it up. Iam lost , completely lost!

 

[Psychopathic]

I can get it to go in overdrive and reverse, takes forever to engage, fluid levels are good,
One thing that concerns me, when I crank it, put in gear, slowly engaes the converter, the truck moves no more then 15-20mph at hi rpms, completely slips, then when I put it in park, the motor "by itself!!" Revs steadily to 4-5k rpms before I can shut it off! I can crank it up and it won't rev by itself until I put it in gear and back in park again