TPS/APPS problems (2 Viewers)

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I actually ordered a new APPS last night, so I'm hoping that fixes things. I'll also clean out the TB

I replaced my APPS this weekend, 160K. Ended up cleaning the throttle body and I am not sure i completely cleared the codes after the first test run. It ran fine until it got to temp, then was back in limp mode. Tried replacing the TPS, which didn't help. Read up. tested new and old tps, both read about the same, so I cleaned everything, TB, all elec connections, and reinstalled original TPS, unhooked batt and let the truck sit for 10 min. No issues since then. Also had to fiddle with TPS to get it on the right initial setting.
 
Checking into TPS/APPS anonymous here -

The 'next thing to do' is not abundantly clear, but replacing the APPS appears to be the most common successful outcome?

Do I wait to see if the issue comes back? If it does come back, am I just risking that I'll be in 'limp mode' somewhere unexpectedly (intimidating as I'm in the mountains often)? Also - what causes limp mode to clear? About 5 starts following limp mode, vehicle was functioning normally even though the dash was still lit like a Christmas tree....however the fact that it can just go limp at any given moment caused me to loose sleep last night...LOL.

Ultimately trying to gauge where this lands on the huge-freaking-problem-a-dar....urgent or less urgent?

P1121.jpg
 
I’m getting a P1126 code so I though to replace the throttle position sensor first since that’s the least expensive option.
This is what my reader says..... thoughts?
D6CCB5C8-BA96-4745-90DD-3021CB1F2613.png
 
I’m getting a P1126 code so I though to replace the throttle position sensor first since that’s the least expensive option.
This is what my reader says..... thoughts?
View attachment 2606730
I am having this same issue. Were you able to resolve this code? I have heard cleaning the throttle body could resolve this issue. I haven’t gotten around to it since this isn’t my DD.
 
I am having this same issue. Were you able to resolve this code? I have heard cleaning the throttle body could resolve this issue. I haven’t gotten around to it since this isn’t my DD.
Not really. I took it to a trusted mechanic and he fiddled with it and said the TPS needed replacing. He cleared the code but it hasn’t come back on yet. So I’ve been riding around like it is but no code yet. However, I did buy a new TB with sensors from Toyota. One day I’ll get around to having it installed. I think that’s the best route instead of chasing down the issue. Here’s another tread on it...
 
One other possibility for limp mode to throw into the mix. My wife experienced the complete lack of throttle response a few times so I read the forums and decided to try cleaning all my sensor connections. No codes.

Then I took a look at the FSM, which had ohm readings specified for APPS, TPS, throttle control motor and magnetic clutch. My magnetic clutch came back low, but not open. I surmised that a recent throttle body cleaning may have gotten some moisture in there which reduced resistance of the circuit. I decided to put it all back together and reset the ECU to see if it happened again. It's been a week of smooth sailing since. Hmm. Any thoughts?

Later today I'll go recheck the ohms and report back. Will also upload a pic of the FSM ohm specs for those components.
 
One other possibility for limp mode to throw into the mix. My wife experienced the complete lack of throttle response a few times so I read the forums and decided to try cleaning all my sensor connections. No codes.

Then I took a look at the FSM, which had ohm readings specified for APPS, TPS, throttle control motor and magnetic clutch. My magnetic clutch came back low, but not open. I surmised that a recent throttle body cleaning may have gotten some moisture in there which reduced resistance of the circuit. I decided to put it all back together and reset the ECU to see if it happened again. It's been a week of smooth sailing since. Hmm. Any thoughts?

Later today I'll go recheck the ohms and report back. Will also upload a pic of the FSM ohm specs for those components.
Posting back. Ohms are still low on the magnetic clutch according to the FSM. Everything else is in spec. No more issues while driving. Has anyone tried ohming sensors? Did you find they were out of spec before replacing them? Here are the FSM values for my 98 LX470.

B1F74D41-C5DE-4F1E-A344-835BCD9CAA44.jpeg
 
Has anyones throttle control motor, or throttle control sensor ever started buzzing to indicate failure? Vehicle Cranks, but does not start. I will test resistance tomorrow when I am back at tools.

 
Where is the TPS located?

Also, these are 2 separate parts, right? And is one more likely to fail than the other?

APPS??
apps.jpg



TPS??

tps.jpg
 
Has anyones throttle control motor, or throttle control sensor ever started buzzing to indicate failure? Vehicle Cranks, but does not start. I will test resistance tomorrow when I am back at tools.



Bumping this. I have a loud buzzing coming from my throttle body motor. I couldn't hear it before as I had a bearing slowly failing on my AC compressor that was covering the noise.

Anyone find this buzzing to be a symptom of a bad motor or sensors?
 
@AimCOtaco bumping this as I see you did a lot of diagnosis historically on a TPS/APPS/Motor issue on your throttle body - is buzzing at the motor assembly and a low/bogging idle a symptom of this assembly going bad?
 
Apologies for digging up an old thread, but does anyone know what the part number is for the APPS on a 2001?

Edit for posterity - looks like it’s 22060-50011
 
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1999 TLC Digging this up, threw the intermittent P0121. Opted to replace the entire throttle body and now truck is throwing continuous P0121 with crap throttle response. Any ideas?
 
I have been trying to solve this issue for years at this point. Luckily my original TB assembly continues to operate consistently enough that it only throws a fit once the vehicle is VERY cold (neg or single digits).

First time it happened, I went into limp mode on the highway. I hopped on here, disconnected battery, made it to work fine. A few weeks later happened again.

Read up on here, bought the full TB from Stevenson Toyota West, brought it to an Indy shop to replace it .. no luck. New TB in their eyes was "defective," I told them to order the part. The new part they ordered, had the same issue and the shop couldn't explain it.

Put the old one in and went about life for about a year until the next really cold morning. Same code, P1121 is back! Went to a different shop, we started with my self ordered part - said its defective, asked if they could order their own throttle body -- which I declined and said I am going to go to the stealership next, because I have no idea what to do next.

Have an appointment in a few weeks at Stevenson Toyota West .. where I am bound to have the same experience.

I have a 1998 Land Cruiser. Thoughts?
 
I have been trying to solve this issue for years at this point. Luckily my original TB assembly continues to operate consistently enough that it only throws a fit once the vehicle is VERY cold (neg or single digits).

First time it happened, I went into limp mode on the highway. I hopped on here, disconnected battery, made it to work fine. A few weeks later happened again.

Read up on here, bought the full TB from Stevenson Toyota West, brought it to an Indy shop to replace it .. no luck. New TB in their eyes was "defective," I told them to order the part. The new part they ordered, had the same issue and the shop couldn't explain it.

Put the old one in and went about life for about a year until the next really cold morning. Same code, P1121 is back! Went to a different shop, we started with my self ordered part - said its defective, asked if they could order their own throttle body -- which I declined and said I am going to go to the stealership next, because I have no idea what to do next.

Have an appointment in a few weeks at Stevenson Toyota West .. where I am bound to have the same experience.

I have a 1998 Land Cruiser. Thoughts?
I'd avoid Stevenson West, they can't keep a good mechanic. Groove Toyota on South Broadway, is much better shop. Guy's in that shop and parts dep, have been there 20 plus years.
 
I have been trying to solve this issue for years at this point. Luckily my original TB assembly continues to operate consistently enough that it only throws a fit once the vehicle is VERY cold (neg or single digits).

First time it happened, I went into limp mode on the highway. I hopped on here, disconnected battery, made it to work fine. A few weeks later happened again.

Read up on here, bought the full TB from Stevenson Toyota West, brought it to an Indy shop to replace it .. no luck. New TB in their eyes was "defective," I told them to order the part. The new part they ordered, had the same issue and the shop couldn't explain it.

Put the old one in and went about life for about a year until the next really cold morning. Same code, P1121 is back! Went to a different shop, we started with my self ordered part - said its defective, asked if they could order their own throttle body -- which I declined and said I am going to go to the stealership next, because I have no idea what to do next.

Have an appointment in a few weeks at Stevenson Toyota West .. where I am bound to have the same experience.

I have a 1998 Land Cruiser. Thoughts?
I will be very interested in the fix. I replaced my TB with new OEM and still have the cold weather limp home mode and P0120 code. It goes away when the engine gets warm or is warm outside but seems to be getting worse.
 
I will be very interested in the fix. I replaced my TB with new OEM and still have the cold weather limp home mode and P0120 code. It goes away when the engine gets warm or is warm outside but seems to be getting worse.
Ugh - this is so confusing to me
 
I’m having the same problem. Seems to yield its ugly head in cold weather. After reading the thread I ordered some marine grade dialetric grease to start with the corrector.
 
I’m having the same problem. Seems to yield its ugly head in cold weather. After reading the thread I ordered some marine grade dialetric grease to start with the corrector.

Is this simply disconnecting, putting the dialectric grease on the female connector prongs and reconnecting it?
 
Yes. I’m suspicious that there is an issue in the connector with years of high heat cycles. I’m wondering if it’s oxidizing where it contacts.
 

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