Engine dies coming to a stop...

[TheBussman]

I know this is like 12 years after the fact but my 1992 I just imported from Japan is having the exact same problem. Did you ever figure it out? I had mine stall out and die driving down a mountain canyon and had been in a shop for the past 2 weeks but the speedometer and odometer failed right before it died as well. Freaky how similar it was to yours apparently. They took apart my dash and they think it was because of exposed copper and someone messing with it in the past. I’ll attach some pictures. If you see this, any help is appreciated.

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the capacitors leak and damage the board sometimes. very very common. hopefully the capacitors can just be replaced and then it will work but other times the traces need repaired and sometimes even more damage is done. Good opportunity to switch to a MPH speedometer.

 

[rhinocrunch]

the capacitors leak and damage the board sometimes. very very common. hopefully the capacitors can just be replaced and then it will work but other times the traces need repaired and sometimes even more damage is done. Good opportunity to switch to a MPH speedometer.

Yeah the shop says they are trying to source a new gauge or solder it. Should the gauge be interchangeable between USDM and JDM?

 

[TheBussman]

Yeah the shop says they are trying to source a new gauge or solder it. Should the gauge be interchangeable between USDM and JDM?

us speedo is plug and play.

 

[jeffro109]

I know this is like 12 years after the fact but my 1992 I just imported from Japan is having the exact same problem. Did you ever figure it out? I had mine stall out and die driving down a mountain canyon and had been in a shop for the past 2 weeks but the speedometer and odometer failed right before it died as well. Freaky how similar it was to yours apparently. They took apart my dash and they think it was because of exposed copper and someone messing with it in the past. I’ll attach some pictures. If you see this, any help is appreciated.

View attachment 3869598

View attachment 3869599

Never did. Hasn't been a recurring issue.

Sometimes after being parked for several days but using the electrical system for camping charging/fridge use, etc. the engine will idle roughly and want to die if higher RPMs are not maintained for a bit. No real idea and no real time to try to chase it.

 

[bdog75]

Sparkplug tube seals in valve cover will do it.

 

[Kernal]

IME any vacuum leak can cause low rpms at idle or even the engine quitting ie: from old/damaged spark plug tube seals, cracked valve cover gasket, cracked or loose breather or PCV valve hoses, cracked air intake hose, ----

 

[rhinocrunch]

IME any vacuum leak can cause low rpms at idle or even the engine quitting ie: from old/damaged spark plug tube seals, cracked valve cover gasket, cracked or loose breather or PCV valve hoses, cracked air intake hose, ----

The mechanic at the shop I took it to told me that when he got it to turn back on it had a really low idle and was constantly on the verge of fully shutting off. So he inspected and looked for any vacuum leaks and didn’t find anything. When he took the throttle body off and cleaned it out, the low idle/ almost stalling problem completely went away and was revving at a normal speed. So I should be inclined to believe the mechanic that it’s now fixed right?

 

[Kernal]

Sounds like he found the culprit.

@rhinocrunch :

Did the mechanic completely remove the throttle body to clean all the internal ports?
Did he replace any other parts, vacuum hoses, clamps, or throttle body gasket, at the same time (charges on your bill)?

 

[rhinocrunch]

Sounds like he found the culprit.

@rhinocrunch :

Did the mechanic completely remove the throttle body to clean all the internal ports?
Did he replace any other parts, vacuum hoses, clamps, or throttle body gasket, at the same time (charges on your bill)?

I think he just took off the intake and accessed it that way. I’ve been driving it today and seems to be just fine going from 60mph down to a stop and not skipping around at all while idle. No he didn’t replace anything, just cleaned it. Now I’m trying to figure out the stiff steering problem because I can definitely tell there’s something up with it after not driving it for 2 weeks, it’s that noticeable. I have no information from the last owner on the power steering pump or when the fluid was last changed.

 

[ajax1]

Does the reservoir have atf in it? Make sure it’s red atf and not power steering fluid. I’d check that first then report back

 

[Kernal]

"I think he just took off the intake and accessed it that way"

@rhinocrunch :

Kinda doubt he took the intake off as there are only four bolts that hold the TB to the intake and then a few small hoses that need to be disconnected.
There are three cables that could be disconnected if the mechanic took the TB to a bench to clean it.

It would help (you) to know exactly what the mechanic did. Not a big deal, but for example if he did remove the intake manifold (upper plenum) the labor would be ballpark $1000, and if he did remove the intake then while it's off the engine there are a dozen other things that should be taken care of.

So if could you look at the bill; what does it say, just "clean Throttle Body" and then what were the labor and parts charges?

There should be a charge for a new TB gasket, maybe a section of fuel and/or a water hose, etc, etc

Point is: many of us on the forum know what else could/should be done while things are apart. One example: there's a small diameter coolant hose that runs off the bottom of the Throttle Body down to the head. You can only access the top connection of that hose when the TB is removed (or even just unbolted and pulled up a bit) you can then easily replace that coolant hose which is known to leak and then reach in from below to attach the other end.

 

[rhinocrunch]

"I think he just took off the intake and accessed it that way"

@rhinocrunch :

Kinda doubt he took the intake off as there are only four bolts that hold the TB to the intake and then a few small hoses that need to be disconnected.
There are three cables that could be disconnected if the mechanic took the TB to a bench to clean it.

It would help (you) to know exactly what the mechanic did. Not a big deal, but for example if he did remove the intake manifold (upper plenum) the labor would be ballpark $1000, and if he did remove the intake then while it's off the engine there are a dozen other things that should be taken care of.

So if could you look at the bill; what does it say, just "clean Throttle Body" and then what were the labor and parts charges?

There should be a charge for a new TB gasket, maybe a section of fuel and/or a water hose, etc, etc

Point is: many of us on the forum know what else could/should be done while things are apart. One example: there's a small diameter coolant hose that runs off the bottom of the Throttle Body down to the head. You can only access the top connection of that hose when the TB is removed (or even just unbolted and pulled up a bit) you can then easily replace that coolant hose which is known to leak and then reach in from below to attach the other end.

It says : THROTTLE VALVE HOUSING - Remove & Replace/cleaning. 1.30 Hours $181.94

 

[Kernal]

OK, so he just removed the TB, not the intake. If he didn't charge for parts then he reused the TB gasket (FSM says to replace it but some people don't)
and the section of fuel (vapor) hose that is usually rock hard where you have to cut it off, he may have replaced it and not charged for 4" of generic hose maybe?

Either way, glad it got fixed.

 

[rhinocrunch]

OK, so he just removed the TB, not the intake. If he didn't charge for parts then he reused the TB gasket (FSM says to replace it but some people don't)
and the section of fuel (vapor) hose that is usually rock hard where you have to cut it off, he may have replaced it and not charged for 4" of generic hose maybe?

Either way, glad it got fixed.

Yeah I drove it up the canyon and back down that it died in 2 weeks ago and had zero problems. Morning cold starts also result in the RPM’s dropping much faster and it idles smoother now at stoplights. Now I’m trying to figure out the stiff steering problem. I could really feel it driving at higher speeds, 55 mph+ . At slower speed it’s less noticeable but it’s definitely something I need to fix. I don’t think it’s anything with the steering because I had it all inspected and aligned just a few weeks ago. Leaning towards the pump or maybe old fluid.

 

[tech_dog]

I had a stretch where my odometer and speedometer were down because of a yellow box failure. My truck started running rough and stalling at stops and while coasting down hills. Replacing the yellow box fixed the speedo, odo, and the stalling & rough idle problem. The ECM must make bad guesses when it gets bad speed data.

I've also had rough/stall from vacuum leaks, as many mentioned. My leak was my valve cover gasket and spark plug seals.

 

[rhinocrunch]

I had a stretch where my odometer and speedometer were down because of a yellow box failure. My truck started running rough and stalling at stops and while coasting down hills. Replacing the yellow box fixed the speedo, odo, and the stalling & rough idle problem. The ECM must make bad guesses when it gets bad speed data.

I've also had rough/stall from vacuum leaks, as many mentioned. My leak was my valve cover gasket and spark plug seals.

How did you end up finding out it was the yellow box?

 

[Kernal]

Which yellow box??


IME stiff steering can be caused by broken trunnion bearings inside the steering knuckles.
Are you running oversize tires?

 

[rhinocrunch]

Which yellow box??


IME stiff steering can be caused by broken trunnion bearings inside the steering knuckles.
Are you running oversize tires?

I’m running 35 inch tires with a 2 inch OME lift. If it was bad bearings wouldn’t it be bad all the time? Or at least not only when I’m at high speeds and turning?

 

[tech_dog]

How did you end up finding out it was the yellow box?

I had what started as an intermittent speedo fail, falling to zero. It would last a few seconds, then minutes, and eventually days. Around the same time I noticed I was sometimes rough at idle, and I'd stall at lights and while going down hill, especially after running at high speeds.

I used the Yellow Box self-test modes and a bypass connector to prove it was the Yellow Box, and ordered a replacement. I was hoping the speedo fix would also fix the rough idle and stalling, and it did. Stalling and rough idle went from common to never after I reestablished a 100% available speed signal.

My first Yellow Box lasted 15 years. That's pretty good, but not Toyota good. I replaced it with the latest version of the same thing.

 

[Kernal]

tech-dog: OK, so yellow box speedometer correction; confusing as the thread was not related to speedo;s

@rhinocrunch : I was referring to the Trunnion bearings (top and bottom) that if broken can cause stiff steering, not the wheel bearings.
But then it should be more noticeable at low speeds IME.

A slipping gear behind the harmonic balancer that drives the power steering pump can cause loss of power steering; have you recently had the harmonic balancer off? If so did you torque the crank bolt to ~305 ft lbs?

Is the PS reservoir reading full when hot?