BMcEL

Not necessarily. And the TPS failed the IDL-E2 and VTA-E2 tests so I know it's bad, not just a hunch.

I'm mainly replacing the TPS because it's dead and if it resolves the OD issue, great. If not, I may troubleshoot the issue further. Eventually the slushbox is coming out and an R150F is going in so I'm not super motivated to troubleshoot it.

Will do.

BMcEL

Put my new Denso TPS in today. All I can say is anyone who complains about this being a difficult job either has female genitalia or very little mechanical experience. Installed and adjusted in under 15 minutes. Did not remove the hood or the throttle body...did it in place with the original hardware. Set my meter to beep on continuity, connected my homemade alligator clip probes to IDL and E2, and adjusted the TPS to cut the IDL signal at .7mm per the FSM.

Drove about 40 miles today and checked for codes. None. Idles like butter now too...not that it was bad before but now it's smoooth. No OD issues today but I'll give it a few weeks before I claim resolution again. Yeehaw.

Mandy Tuning

its a easy task

BMcEL

Ya I can't believe how many people say it's a PITA and that you should remove the hood and/or throttle body.

Mandy Tuning

maybe if you are 7,11" of height need to remove the hood,6.3 and only need to remove the thermosthat housing

1st 4runner

I just bought my first 4runner. It is a 1991, V6, auto, 4wd. I have a transmission problem and trying to figure out repair/rebuild cost but can't figure out which transmission it has. Anybody have an idea? thanks

BMcEL

Welcome to YT!

You have the A340H. It's labeled on the driver side door pillar...circled below.



Search function works better than thread-jacking BTW.

UPDATE - it's only been two days but I haven't had any OD issues yet and I can't believe how good it idles when it actually sees the IDL signal from the TPS.

1st 4runner

thanks for your help. brand new to this site and had trouble navigating. did not mean to jack the thread.

BMcEL

No problem...for future reference there's a big search button near the top of the screen.

BMcEL

No OD issues all week and I have noticed smoother shifting, super steady idle, and the very faint pinging under heavy load seems to be cured. No MPG checks yet and probably won't be...I don't keep my foot out of it enough to notice a difference anyway.

I'll update again if the OD issue returns.

DetroitStyle

iTrader: (1)

I picked up a '91 4Runner 3.slow automatic... it's doing the same thing. Bought the ECT sensor today. Will be installing tomorrow and reporting back. Thanks for the info Yotatech!

RiverRat Cargel

I have a 87 turbo with the R150 I belive, having some of these issues. Random idle, likes to die when I give it gas, acts like a air/fuel mixture issue. I know my temp sensors on the motor are old and janky, and someone messed with my electronics cause my shifted lights, nutural start, OD lights don't work. Gonna try some of these test this afternoon and see if I can dial it in, since nothing else iv tried has fixed it.

BMcEL

Replacing my ECT fixed it for a while but the TPS ultimately resolved it. I think both sensors were on their way out. Test your ECT before you replace it. No sense in replacing good parts. If it does test good, test the TPS next. If the TPS is good, it could still also be the trans temp sensor. Mine is taking longer and longer to get into OD now, so I think the third and final sensor that has an affect on OD engagement is also on it's way out.

First off, this thread is in regards to an automatic transmission problem...my truck never ran poorly. Second, the R150 is a manual transmission and was not available in 1987...this thread is on the A340 automatic. With that said, the ECT and TPS can cause the motor to run poorly so some of the info in here may apply to your situation.

RiverRat Cargel

Sorry didnt meant to thread jack, its a R151f i belive, auto with OD. I AM having OD/ Shifting issues and didnt know till not they could be related to TPS and sensors. The other issues could also be related i guess. Things how i spent hella time working on my fuel and air systems, maybe someone with same issues could by-pass those steps i took with no progress and go straight to the real problem.

BMcEL

R151 is also a manual transmission. You have the A340F. If your truck is running like crap because of the TPS and/or ECT, it is very likely that they are also affecting the transmission.

astynx

Mine took awhile to shift to overdrive during cold weather. New toyota oem t-stat was installed and now it shifts into overdrive sooner. I believe oem t-stat is a '2- stage' opening t-stat. This may be something for others to try that are having this problem.

BMcEL

Another update. TPS pretty much resolved it but once in a great while it would still do it. The only remaining sensor that can cause this that I did not check was the trans temp sensor. Seeing how both the engine coolant temp sensor and the TPS made it much better, I believe it was just all three sensors that were on their way out.

I would test/replace the trans temp sensor just to confirm it, but my trusty A340 is now the victim of an R150F swap.

[/thread]

DetroitStyle

iTrader: (1)

I never got around to replacing my ECT sensor, as I've determined that mine only does it when the cruise control is engaged and I am a bit too busy these days to work on it. I can live with it for the time being.

quattro1.8t03

This may be a rookie question, but does the shifting into overdrive happen in every gear or just the last one?
We just replaced my brothers A340 with a used one and he is having problems with the rpm's getting very high before it shifts into the next gear. Is there a way to adjust when it shifts? Thanks for any help on the this.

BMcEL

Spent $15 for two-day access to Toyota TechInfo and 4-5 hours opening/saving EVERY document Toyota issued relating to my '90 one by one (TSBs, repair manual, wiring diagrams, etc.), and I came across this:




It was apparently a common enough issue to warrant a service bulletin. The other parts I mentioned in this thread can still cause the same issue, but if this was a known problem, it's worth looking into. Even though I removed the auto already, I'm still going to tear into it since the ECM uses the THW signal for more than just OD control.

Figured I'd post it up.