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Hey all,
ive got an 89 4Runner, 22RE, and it’s throwing a code for the TPS. It’s alsp starting rough and with a wacky all over the place idle, which I’m assuming is because of the faulty TPS.
Here my question. Do I need to replace the TPS or can I simply remove it clean and put it back on. Some fellow at an auto parts store suggested that I could, but I’m not sure... if it’s the springs getting old then cleaning wouldn’t do anything right?
Anyway, it’s an sort of expensive part so I’m trying to see if I need to change it ASAP. Or clean it or what.
Look for posts by wallytoo and myself, pretty sure it was Wally that shows how to tight up the return spring in my case I had one with a rock lodged in the spring and showed how to disassemble.them for cleaning or board replacement.
However two much more likely causes are the dash pot or a sloppy worn out throttle plate rotating assembly..
Exactly which code are you getting.
Best access to the screws is with a screw driver meant for household door handles, it has an s bent to it.
Dang, how’d you get a rock in your throttle position sensor? so I was getting two codes, two flashes and two flashes- which I believe is the coolest tempature sensor- and four and one -which I believe is the throttle position sensor.
Dang, how’d you get a rock in your throttle position sensor? so I was getting two codes, two flashes and two flashes- which I believe is the coolest tempature sensor- and four and one -which I believe is the throttle position sensor.
Either of those codes could be cause for the odd idle.
If you unplug the tps does it make it idle better, unplug the temp sender next. Unplugging these should put the computer into a fail-safe condition where it will make an assumption of engine temp and base fuel off of engine load. Next olug each back in one at a time ensuring they are clean connections, fully seated plugs. The unplug test will indicate if it's bad wiring (no change to idle) or bad sensors, but there is no excuse not to have a multimeter which you'll need to adjust a new tps anyway.
The kids I bought my 4runner from had it out in the mud when the turbo blew, and one of the mounting ears was missing off the tps with a chunk of the case missing
Either of those codes could be cause for the odd idle.
If you unplug the tps does it make it idle better, unplug the temp sender next. Unplugging these should put the computer into a fail-safe condition where it will make an assumption of engine temp and base fuel off of engine load. Next olug each back in one at a time ensuring they are clean connections, fully seated plugs. The unplug test will indicate if it's bad wiring (no change to idle) or bad sensors, but there is no excuse not to have a multimeter which you'll need to adjust a new tps anyway.
The kids I bought my 4runner from had it out in the mud when the turbo blew, and one of the mounting ears was missing off the tps with a chunk of the case missing
From post #24 in 36522's thread "tps surgery"
oh yeah, the tps was definitely faulty. The idle was all over the place unless the TPS was disconnected. Just changed it, fixed the idle, but still stuff to figure out.
update:
ive got the codes 22 (temp sensor) and 51. I’m a little unclear on what’s triggering the 51 and how to deal with it. 51 can be the air condition or the throttle position sensor. I literally just changed my sensor. And did a lot of through checks to make sure it was placed right-and it stoped the surging idle that I was having.
22 makes sense because the pigtails to my coolent temp sensor had a broken wire so I just attached them straight to the other end of the connector while I order a new one- only found a new on amazon-
. Just in case anyone is looking for it. Anyway, fixing that as soon as I get it. Meanwhile I also changed that sensor and it’s still reading the temp even though the connection is not ideal.
but 51?? What could that be? I’m not even sure what the throttle position sensor circuit is, and the manual is being extremely unhelpful.
Also if just came on not long ago, and the air conditioning has never once worked. It’s the old R-12 system and forget changing that over. I can live without it.
Code 51, likely means the throttle position sensor (tps) wasn't adjusted properly when you replaced it. It needs to be put into a specific position such that the idle switch circuit is closed when not pressing the throttle pedal but the switch contacts open with very little throttle movement.
There are lots of threads that can give some insight to this, a good write up by Roger Brown (4crawler) on his website, and you will find this information in the manual also.
You need a multimeter, a set of feeler gauges, a screwdriver, and some patients if it's your first attempt.
Basicly you hook up the meter to the lower two plug prongs with it set to ohms (resistance), slightly loosen the sensor, place a feeler gauge between the rotating section of the throttle linkage and rotate the tps untill you have the specified reading (a few hundred ohms from memory) then tighten the tps back down. Once this is done you verify the setting reads near zero (switch closed) with no feeler gauge, and open (OL, zero L, open leads) with the feeler gauge in place.
Code 51, likely means the throttle position sensor (tps) wasn't adjusted properly when you replaced it. It needs to be put into a specific position such that the idle switch circuit is closed when not pressing the throttle pedal but the switch contacts open with very little throttle movement.
There are lots of threads that can give some insight to this, a good write up by Roger Brown (4crawler) on his website, and you will find this information in the manual also.
You need a multimeter, a set of feeler gauges, a screwdriver, and some patients if it's your first attempt.
Basicly you hook up the meter to the lower two plug prongs with it set to ohms (resistance), slightly loosen the sensor, place a feeler gauge between the rotating section of the throttle linkage and rotate the tps untill you have the specified reading (a few hundred ohms from memory) then tighten the tps back down. Once this is done you verify the setting reads near zero (switch closed) with no feeler gauge, and open (OL, zero L, open leads) with the feeler gauge in place.
Originally Posted by Co_94_PU
Code 51, likely means the throttle position sensor (tps) wasn't adjusted properly when you replaced it. It needs to be put into a specific position such that the idle switch circuit is closed when not pressing the throttle pedal but the switch contacts open with very little throttle movement.
There are lots of threads that can give some insight to this, a good write up by Roger Brown (4crawler) on his website, and you will find this information in the manual also.
You need a multimeter, a set of feeler gauges, a screwdriver, and some patients if it's your first attempt.
Basicly you hook up the meter to the lower two plug prongs with it set to ohms (resistance), slightly loosen the sensor, place a feeler gauge between the rotating section of the throttle linkage and rotate the tps untill you have the specified reading (a few hundred ohms from memory) then tighten the tps back down. Once this is done you verify the setting reads near zero (switch closed) with no feeler gauge, and open (OL, zero L, open leads) with the feeler gauge in place.
I did that. It took forever, but I got it right in spec. I used a multimeter, and tested it with the throttle in four different positions, closed, .57mm, .85mm and full open. Crossing the correct terminals with my ohm meter.
Before I did I it was reading the TPS code 41. Why is it still TPS but a completely code? I may go back in there and recheck the TPS with a different set of feelerguages just Incase those were worn and gapping wrong? But what else might it be?
Don't have the exact size feeler. Using 0.203 + 0.66 = 0.863mm.
Press the stop against the feeler and the stop screw, there is a nice flat spot on top.
a moment about the FSM TPS adjustment procedure. It has you insert the TPS at its maximum CCW orientation. This is so the engagement is oriented correctly with the throttle pushing the sensor. Then it goes in to taking up the slack, and tells you to insert the 0.47mm and "rotate cw until the needle deflects". You need to take up any slack between the throttle and the sensor and any slack in the sensor. So if it's not zero with the 0.47mm, and it fluctuates at all when you touch it that is deflection tighten it! The next two will be in spec with the .5mm it's under 2k, .8 it's open.
You can totally tweak it with in the limits. As long as .5 isn't to close to open and 8 is open. About more on his in a second.
Anyways I stabbed that blind just took out the mechanical slack tightened it up and tested with .5 and .8mm.
Let's just assume it is adjusted properly for a second..
Other causes of code 51 are.
The AC is turn on while the jumper is in place.
Someone moved the throttle pedal while the jumper is in place.
And worst case (unlikely) the wire is damaged.
(Edited out the non relevant bit about throttle angle)
Let's just assume it is adjusted properly for a second..
Other causes of code 51 are.
The AC is turn on while the jumper is in place.
Someone moved the throttle pedal while the jumper is in place.
And worst case (unlikely) the wire is damaged.
dang, looks like I’ll have to go through the process again just to be sure. I got a new set of feeler gauges.
Question, my truck is also having issues starting after sitting for a few hours/overnight. It starts then dies unless I put my foot full on the throttle for a minute first. Also it’s progressed to now dying occasionally while driving and coming to a stop (stop sign etc) so pretty much any time I take my foot fully of the pedal. But it only dies ocosinally, not every time. I’m baffled. Could this be stemming from the same issue?
You very likely didn't need another set of feeler gauges, can't imagine what you've been doing with them that could ruin them. That's kind of like ruining a ruler...
Yes very possible its the same issue, also very possible its something you've done while in the engine bay trying to solve it
You very likely didn't need another set of feeler gauges, can't imagine what you've been doing with them that could ruin them. That's kind of like ruining a ruler...
Yes very possible its the same issue, also very possible its something you've done while in the engine bay trying to solve it
What is the status of that coolant sensor?
update:
i got the coolent temp sensor pigtail in the mail and installed it. All codes gone. Did a little research into the effects of a defective temp sensor... it can cause the catalytic converter to be clogged. And the cat just started making crazy noises. Also the truck stopped accelerating, and was periodically turning off at a stop. So that all seems to make sense. The throttle body and TPS all looks good.
So soon I’ll be changing out the cat, and clean out the o2 sensor. And see if that solves the acceleration issue. I think it will, it’s also started to leak exhaust from the manifold, which just backs up the story of the cat being faulty.
Thanks for the update, and good job on the research and diagnostics.
I'd suggest you forego attempting to clean the oxygen sensor and just replace it with a new denso unit. They have a life span, if you don't know it's age best to just swap I'm the new part while it's out and know it's good for another decade than have to wonder if you will be in there again come spring because it finally died.
Don't forget lots of penetrating oil, repeated vigorously on those o2 mounting studs... Lile a quarter or more of a can applied over the span of a few days or week.. And you still might break a stud, so best of luck!
I'll elaborate, and speculate, on what you found on coolant sensor..
The coolant sensors are important for determining the air fuel ratio. I high fuel to air ratio results in excess fuel reaching the converter. The converter burns this fuel and can become very hot to the extent the catalyst ablates from the substrate and plugs up the cat, sometimes enough the substrate melts and becomes detatched. This is a self induced/reinforced destructive cycle that eventually blows out upstream gaskets or does other such nasty things..
Thanks for the update, and good job on the research and diagnostics.
I'd suggest you forego attempting to clean the oxygen sensor and just replace it with a new denso unit. They have a life span, if you don't know it's age best to just swap I'm the new part while it's out and know it's good for another decade than have to wonder if you will be in there again come spring because it finally died.
Don't forget lots of penetrating oil, repeated vigorously on those o2 mounting studs... Lile a quarter or more of a can applied over the span of a few days or week.. And you still might break a stud, so best of luck!
I'll elaborate, and speculate, on what you found on coolant sensor..
The coolant sensors are important for determining the air fuel ratio. I high fuel to air ratio results in excess fuel reaching the converter. The converter burns this fuel and can become very hot to the extent the catalyst ablates from the substrate and plugs up the cat, sometimes enough the substrate melts and becomes detatched. This is a self induced/reinforced destructive cycle that eventually blows out upstream gaskets or does other such nasty things..
The wires that connect to them should be checked as well. The "bend" to the sensors breaks the insulator and now they're exposed to the elements. I was frustrated for yonks because my engine in my 22RE would hesitate after I hit a bump. On a random, "let's look at the engine" over beers, my friend pointed out that the wire to the sensor just fell off the crimped on connector that had been attached poorly by the PO. I re-attached and problem went away for good.
so I brought the truck into the shop and got a new cat installed and they also fixed up a hole in the manifold.
The mechanic also noticed that beyond that I was running quite rich, and he had to adjust the screw under the trottle that controls the fuel ratio. That worked great for a while. The truck was running like a dream. Just the other day however, it started to die at an idle again. Not every time I turn it on, but maybe half. So I’ll start it up and it sounds fine, the I start driving and ask take my foot on and if the gas it lurches a lot. Then, when I slow down for a turn or stoplight, the truck shuts right off.
Any ideas?
so I brought the truck into the shop and got a new cat installed and they also fixed up a hole in the manifold.
The mechanic also noticed that beyond that I was running quite rich, and he had to adjust the screw under the trottle that controls the fuel ratio. That worked great for a while. The truck was running like a dream. Just the other day however, it started to die at an idle again. Not every time I turn it on, but maybe half. So I’ll start it up and it sounds fine, the I start driving and ask take my foot on and if the gas it lurches a lot. Then, when I slow down for a turn or stoplight, the truck shuts right off.
Any ideas?
You have an electronic fuel injection system, there are no screws that adjust mixture. Show us what they "adjusted".
You have an electronic fuel injection system, there are no screws that adjust mixture. Show us what they "adjusted".
right, I understand that. I definitely am still learning how everything works, and don’t quite understand this system quite yet.
[img]blob:https://www.yotatech.com/002acf09-b505-4d92-815f-a67d3df3cc8a[/img]
right, I understand that. I definitely am still learning how everything works, and don’t quite understand this system quite yet.
[img]blob:https://www.yotatech.com/002acf09-b505-4d92-815f-a67d3df3cc8a
09-21-2018, 07:41 AM
