Optimus

Hello,

I've got a 1990 4Runner 4x4 with an auto tranny that operates quietly and shifts smoothly (when working right), however about half the time it seems to get into this "lack of power mode" in which it appears to go from first gear then skip 2nd, and go into third. It will take off in 1st gear just fine but only go about half the time it normally would before shifting into third gear, then it takes forever to get up to speed! If I shift manually from low to 2nd to drive, it works fine. I thought perhaps it was the shifter solenoids, but there doesn't seem to be a combination of on/off between the two switches that would only affect 2nd gear. All other gears are not affected. There are no trouble codes what-so-ever.

The problem happens when the engine/tranny are warm or cold. No apparent pattern. Tranny fluid is good and at the proper level, and I've inpected the cable on the intake manifold with the small barrel used for alignment of the cable. Nothing has worked.

Out of the blue, the problem will happen. The 4Runner will have been running fine for an infinate amount of time, then all of a sudden the next time I come to a stop it can start up.

What do you think?

Thanks,

Shawn F.
toyota_t100@hotmail.com

Jay

Electronically Controlled Transmission Course 262 ( 19 pages )

It has the failsafe function chart in it. ( Page 15 )

I am not sure the problem. The whole part about manually shifting second, blows my only theory out of the water. Im still thinking.

Jay

Optimus

After reading that, I'm wondering if the #1 solenoid is bad and what feels like 1st gear for a brief few seconds on take-off is just 3rd gear but with the converter slipping, then it locks up and the vehicle turns into a turd. I'm still reading the doc (Thanks!), but perhaps manual shifting into 2nd is not possible at all if the solenoid is bad? It just doesn't seem to me like a solenoid failure can be intermittent. It would seem like it either works or it stops working for good....

I've checked the TPS twice, and it seems to be adjusted right. I did notice on the cable adjustment that the metal thread housing that has the 2 nuts to secure it to the intake manifold can be pulled loose from the rubber/plastic cable housing. Perhaps the cable actually is adjusted wrong? Or would an out of adjustment cable just cause different symptoms.... hmmm...

I should probably pay closer attention to symptom details and see what I come up with. A few other thoughts for now.

Regardless if the problem is happening or not, I can hit the O/D button and shift into or out of O/D. If the problem is happening, I can be tooling along at 50mph or so comfortably with O/D off, then turn it on and feel the tranny shift into O/D. I can feel it downshift when I switch O/D off.

When the problem is happening, what appears to be first gear only lasts few about 4 seconds (if that) when I first take off from a dead stop, then what appears to be third (turd) gear kicks in and it takes forever to get up to speed (especially if going up a hill!). If trying to go up a hill with the prolbem occuring after it's kicked into 3rd gear and I have traffic behind me, I occiasionally shift from D to 2nd and get going fast enough until I can shift back into D.

Perhaps it's a computer problem, either ECU or ETC?

Optimus

Here's perhaps a stupid question--if the solenoid(s) is(are) sticking, are there any transmission fluid additives that actually work or must they just be replaced?

Jay

A solenoid can be intermittent. It definitally sounds like a a solenoid problem. I would have little confidence in any kind of additive, in fixing the problem.

Jay

Optimus

Ok, took it for another drive tonight. Of course it wouldn't do it until the last 2 miles of a 30 mile drive.

A possibly important thing I forgot to mention in all of this is that when the above issues are happening, the tranny will NOT downshift a gear when flooring the gas pedal. You know, like when on the freeway in 4th gear and you floor the pedal so it downshifts into 3rd to pass someone? It won't do that in any gear when the tranny has the above issues.

Ok, now to get back to tonight's test drive. What feels like first gear then a shift to third perhaps might just be starting out in third with the converter slipping in third and then locking in third and feeling like a shift. In other words it might not be starting out in first gear. It could be starting in 3rd or second. With the shift problem happening and O/D off, if I floor the gas pedal from a dead stop it will accelerate (seemingly slower than when in true 1st gear) and then "something" happens (either lock the converter or shift) at about 10-12 mph where it will stay in that gear (presumably 3rd gear) with no shifting or converter changes and go comfortably up to 50mph unless I turn overdrive. If I slow back down to a stop it will start out the same way again.

When the vehicle was operating properly and in PWR mode, the tranny would shift from 1st to 2nd anywhere from 17-25 MPH and from 2nd to 3rd from 36 - 42 mph. This was determined from 3 dead stop starts.

rpeAMP

I had a similar problem and it turned out to be the fuel injectors...

dragondriver5

Interesting. I'm having the EXACT same issue on my 87 4runner. Injectors you say? I can't fathom why this would change how the transmission shifts. Can you please explain?

Aartaxx

SAME PROBLEM! But it only happens when my ect is set on normal. Truck shifts fine on power setting. Weird.

dragondriver5

Wow this tread is old now lol.. Since I last wrote mine has progressivly gotten worse. A few days ago I swapped out the transmission ECM. The first day of driving it there wasn't any change, but the past two days its been shifting better than it ever has. Doesn't really make any sense at all. Temp doesn't seem to make a difference and neither does how often I drive. Sometimes it will drive fine for 20 miles and then suddenly downshift for no reason and not want to switch gears.

I suppose it's just 25 year old electronics acting up. Which is why I'm swapping in a 5 speed soon. Tired of it