Lost Torque on Highway this Morning (1 Viewer)

[jackhossross]

Was driving into the office this morning, very cold. Was on I-25 north in Denver when suddenly I completely ran out of power or torque.

Batteries are fine, car is remaining on. And idling at 600ish rpm. Check engine light popped on and all oomph was lost.

Started it back up and everything seems to be fine, oomph is back - idling a bit higher after I turned on heat as it’s freezing this morning. Check Engine light is remaining on.

Currently on the side of the road waiting for AAA.

Weird stuff, ever happen to anyone?

 

[AlpineAccess]

I had this happen one time a few years ago in Frisco. Was about -5 at the time.

I disconnected my battery and reconnected and the CEL cleared and I was back motoring. Tried pulling codes but nothing. Hasn't come back since.

I've assumed it was something to do with O2 sensors and safe mode but never got to the bottom of it. Certainly don't want it to happen again as it put me in an unsafe situation (as I'm sure you dealt with today).

 

[jackhossross]

I had this happen one time a few years ago in Frisco. Was about -5 at the time.

I disconnected my battery and reconnected and the CEL cleared and I was back motoring. Tried pulling codes but nothing. Hasn't come back since.

I've assumed it was something to do with O2 sensors and safe mode but never got to the bottom of it. Certainly don't want it to happen again as it put me in an unsafe situation (as I'm sure you dealt with today).

I was reading a thread with this same issue so I just did the same. Drove into work, I will replace sensors and probably fuel pump and go along with my life *hopefully*

 

[AlpineAccess]

I was reading a thread with this same issue so I just did the same. Drove into work, I will replace sensors and probably fuel pump and go along with my life *hopefully*

Can you link the thread?

Fuel pump shouldn't be an issue at those temps unless it's a problem at other temps.

That being said I would be willing to bet that after we cleared logs and reset with pulling the battery it self corrected. Which is why for me it hasn't come back. I haven't changed O2s but gave it a really good Italian tune up and pull my battery cable to reset things on the first cold day of the year.

 

[mkntrds]

In my case it was the Accelerator Pedal Position Sensor

 

[Stuckinthe80s]

Do you have a scanner to check the code that's forcing the check engine light? It may be one of the sensors on the throttle body and it's causing the ECM to go into limp mode. This was happening on my 1999 every winter until I replaced the throttle body. A scanner will tell you which sensor with an associated code.

 

[jackhossross]

Can you link the thread?

Fuel pump shouldn't be an issue at those temps unless it's a problem at other temps.

I'm thinking O2s because the oxygen density and temps would be outside of the ECUs learned parameters from daily use, it runs super rich to compensate and when the O2 gives super rich readings multiple times in a row we get a CEL and safe mode. @J1000 thoughts on this as you've reworked fuel and exhaust systems?

That being said I would be willing to bet that after we cleared logs and reset with pulling the battery it self corrected. Which is why for me it hasn't come back. I haven't changed O2s but gave it a really good Italian tune up and pull my battery cable to reset things on the first cold day of the year.

Ih8mud Fuel Pump Thread Example

 

[jackhossross]

Do you have a scanner to check the code that's forcing the check engine light? It may be one of the sensors on the throttle body and it's causing the ECM to go into limp mode. This was happening on my 1999 every winter until I replaced the throttle body. A scanner will tell you which sensor with an associated code.

I don't but am comfortable grabbing one, came from Volkswagen and Audi world with a VAGCOM unit. I will grab one thanks.

 

[Trunk Monkey]

APPS for me too when it got really cold. CEL will tell you what it is.

 

[87warrior]

Any of the bluetooth OBDII dongles + an app will get you what you need to scan for codes.

My bet is on the APPS or TPS as well based on symptoms. I see you have a 98. Did your cruiser happen to 'wake up' when the accelerator pedal was pushed all the way down? At the end of the pedal travel the throttle cable mechanically opens the throttle plate part way on the earlier 100's.

 

[jackhossross]

Any of the bluetooth OBDII dongles + an app will get you what you need to scan for codes.

My bet is on the APPS or TPS as well based on symptoms. I see you have a 98. Did your cruiser happen to 'wake up' when the accelerator pedal was pushed all the way down? At the end of the pedal travel the throttle cable mechanically opens the throttle plate part way on the earlier 100's.

Can't say I was comfortable with flooring it as I lost power. I ordered an OBDII reader and it delivers this afternoon, I'll update this thread with what I find this evening.

 

[MongooseGA]

I experienced sudden loss of power a few times earlier this year. In my case, it was always in higher ambient heat, after having driven at highway speed for a while and usually during some kind of acceleration (overtaking for example). Here's what I was experiencing: (from this thread: P0500 Speed Sensor A - https://forum.ih8mud.com/threads/p0500-speed-sensor-a.1008893/page-2#post-14601588 )

Hey look! I'm back in this thread again!

Ok so mine has been acting really funny recently, and it's getting worse now.

My speedometer has been mostly non-op for most of the year. Every now and then it'll work and display correct(ed) speed, but it's rare. Enough so that if either my fiancee or I drive the truck and the speedo works, we celebrate it to the other later. Best I can tell, the stepper motors in the cluster are going bad as they flutter around sometimes at initial start-up. I can deal with it for now as I have speed on the SG and the cluster repair is $700.

Within the last few weeks, my cruise control has begun just turning itself off. I can hold speed, then it turns off and the icon blinks once or twice in the cluster. I can turn it back on and it'll work for a bit, then go out. This isn't every trip. I noticed it happening mostly at times the speedometer is operating. OK, maybe a tie there. The speedo needle will jump in 10-20MPH increments, then the cruise goes. My initial thought was that the cruise couldn't reconcile the erratic speed readings, so just turned off by default.

Over the weekend was the first time I've actually lost throttle. Almost always while accelerating at highway speed, there's just no response from the pedal for a second. Happened twice on a 3 hour drive, only occurred while using cruise.

Today I was not using cruise, speedo was non-op, and the throttle went out on the 285 perimeter. I coasted for a good 3-4 seconds before it came back. I noticed the speed at my SG was displaying 0MPH, and the truck threw the p0500 code.

I can kind of deal with the annoyance of the speedo and cruise being intermittent, but I can't deal with losing throttle while driving. The speed sensors are a cheap part and I plan to swap a new one just to be safe. Has anyone else ever just straight-up lost throttle??

The fix for me was a new speed sensor on the transfer case. Issue has not returned. Definitely let us know if you find anything with a code reader.

 

[Stuckinthe80s]

Can't say I was comfortable with flooring it as I lost power. I ordered an OBDII reader and it delivers this afternoon, I'll update this thread with what I find this evening.

I might be jumping the gun here but just wanted to pass on some info...

The throttle body from Toyota is around $500 new and includes the miscellaneous sensors everyone is talking about. If you can swing it, you may consider just replacing the whole unit instead of messing with each item. They all go bad over time as well as the mechanical components inside the throttle body itself. In the long run, it will be cheaper and less of a headache to replace it all in one go. Well, if the price doesn't keep dropping. The TB was ~$1k not even 10 years ago, it was $580 when I bought it 2 years ago, and now it's down to $490.

 

[jackhossross]

I might be jumping the gun here but just wanted to pass on some info...

The throttle body from Toyota is around $500 new and includes the miscellaneous sensors everyone is talking about. If you can swing it, you may consider just replacing the whole unit instead of messing with each item. They all go bad over time as well as the mechanical components inside the throttle body itself. In the long run, it will be cheaper and less of a headache to replace it all in one go. Well, if the price doesn't keep dropping. The TB was ~$1k not even 10 years ago, it was $580 when I bought it 2 years ago, and now it's down to $490.

How difficult of a task is this? I can grab a TB from Toyota here in Denver for under $500.

 

[Trunk Monkey]

Read the codes before you start shopping for whole new throttle bodies.

 

[Stuckinthe80s]

How difficult of a task is this? I can grab a TB from Toyota here in Denver for under $500.

It's not too bad. I think it took me less than an hour.

Yes, I ordered mine online and picked it up at Stevenson in Lakewood:

1999 Toyota Land Cruiser 4.7L A/T Fuel Injection Throttle Body - 2203050142 | Stevinson Toyota West, Lakewood CO

Fuel Injection Throttle Body. 1999 Toyota Land Cruiser 4.7L A/T. Genuine Toyota Part - 2203050142 (22030-50142, 2203050140, 2203050141). Ships from Stevinson Toyota West, Lakewood CO

parts.stevinsontoyotawest.com

@Trunk Monkey is right about verifying what the issue is first though.

 

[jackhossross]

It's not too bad. I think it took me less than an hour.

Yes, I ordered mine online and picked it up at Stevenson in Lakewood:

1999 Toyota Land Cruiser 4.7L A/T Fuel Injection Throttle Body - 2203050142 | Stevinson Toyota West, Lakewood CO

Fuel Injection Throttle Body. 1999 Toyota Land Cruiser 4.7L A/T. Genuine Toyota Part - 2203050142 (22030-50142, 2203050140, 2203050141). Ships from Stevinson Toyota West, Lakewood CO

parts.stevinsontoyotawest.com

@Trunk Monkey is right about verifying what the issue is first though.

Verified, but I’d hate to be stranded for any of these reasons. I have a wife and two kiddos, so might try to identify all the potential and take care of them.

Accelerator Pedal Position

 

[suprarx7nut]

Can't say I was comfortable with flooring it as I lost power. I ordered an OBDII reader and it delivers this afternoon, I'll update this thread with what I find this evening.

Sounds like my experience with the APPS (throttle body sensor) failure. Oddly enough, it has a fail-safe of sorts that does indeed involve flooring it. Not the natural reaction, but it's the "limp to safety" fix.

It's been long enough now that I fear this might be misremembered so take this with a grain of salt: The throttle body on the early 100 (I forget what year it was that completely removed the throttle cable) is a hybrid "drive by wire" approach where it's partially electronically controlled at the butterfly valve, but a physical cable is still present and will mechanically force the valve open if you give it close to 100% throttle. It allows you to floor it and get a smidge of power to shuffle off a highway.

Verified, but I’d hate to be stranded for any of these reasons. I have a wife and two kiddos, so might try to identify all the potential and take care of them.

Accelerator Pedal Position

View attachment 3182487

Yup, time for a new throttle body (or at least the sensor portion). You can get just the APPS for $100-200 I think, but I'd get the entire TB if you can source a genuine Toyota part for $500. That should make install easier as well and you replace more wear components in the process.

 

[jackhossross]

Sounds like my experience with the APPS (throttle body sensor) failure. Oddly enough, it has a fail-safe of sorts that does indeed involve flooring it. Not the natural reaction, but it's the "limp to safety" fix.

It's been long enough now that I fear this might be misremembered so take this with a grain of salt: The throttle body on the early 100 (I forget what year it was that completely removed the throttle cable) is a hybrid "drive by wire" approach where it's partially electronically controlled at the butterfly valve, but a physical cable is still present and will mechanically force the valve open if you give it close to 100% throttle. It allows you to floor it and get a smidge of power to shuffle off a highway.




Yup, time for a new throttle body (or at least the sensor portion). You can get just the APPS for $100-200 I think, but I'd get the entire TB if you can source a genuine Toyota part for $500. That should make install easier as well and you replace more wear components in the process.

I’m just going to do the full boat, I don’t want to be somewhere and have an issue with some other part of it later.

I should say I have been experiencing a whining noise from the front engine compartment over the last couple weeks. Hoping this has something to do with it!

Appreciate all the help!

 

[suprarx7nut]

I’m just going to do the full boat, I don’t want to be somewhere and have an issue with some other part of it later.

I should say I have been experiencing a whining noise from the front engine compartment over the last couple weeks. Hoping this has something to do with it!

Appreciate all the help!

I like that attitude. Do it once and do it right.

If the front end whine remains, it might be time for a thorough timing-belt job. The "90k service" technically only requires a few parts to be replaced, but I've found most the pulleys in that area are toast once you're beyond that first 90k/10 year service. Another instance of "while you're in there" work that I think is wise to tackle, but is often skipped.