I have been trying to figure out some possible reasons why it is doing this. I have searched this site and have been reading my Hanes manual, as well as discussing the problem with a mechanic. I have limited mechanical knowledge, but I try to do as much as I can to my own car, if for nothing else then I love my 4runner and want to make sure it is treated well so it will last me a long time. Any help you all could give me would be very appreciated, as I am trying to fix it on my own, if it is possible.

Scenario:
I was driving on the interstate yesterday and I got off at an exit. As I slowed to a stop light, the engine sounded like it was straining and as I slowed to around 5 mph it died. I put it in park and turned the key to start it. It started fine, although the idle sounded different, more rough I think, and when I put it in any gear it died. Not being able to get it driving again I had it towed back to my house and then went and ate some turkey.

Additional info:
My check engine light, along with the VTSC (I think this is the abbreviation) and the TRAC lights have been on for many months now. A few months ago the same thing happened to me: car died in gear. I took it to my regular mechanic, and he couldn't figure it out, so he said he just "reset" the computer and it started running normally again. After about 2 weeks the lights came back on but the car continued to run fine (at least to me). So I did some reasearch and found out that the oil from that fancy K&N air filter I put in the car when I bought it 3 years ago can coat the MAF sensor and foul it. I also went to Autozone and had someone that worked there hook up the scanner and read the error code, which read a lean mixture code. I promptly put a disposable air filter in and cleaned the MAF, as well as the trottle body. This didn't make the lights go away though. I had unhooked the battery while I was working on the car and when I hooked it back up the lights had gone away, but promptly returned to mock me after 2 days. I fear this is what my mechanic did, and I would really hate to take the car to him and have hime do something equally easy, get my car running and then charge me another 60 bucks.


Long post but I wanted to provide alot of information for those that might have some ideas about what is wrong.
My current ideas include possible vacuum leaks, although the guy I spoke with said if this were the case there would be a decrease in rpms at higher speeds.
Fuel pump: bad scenario, these seem to be expensive.
Water in the gas: I hope not - I have already run almost half of what is in the tank, why would a problem pop out now from that I wonder?
Leaking EGR valve: not sure where this is or how to fix it, I kinda know what it is and there is info on it in my Hanes.
Fuel filter: I am going to replace this right now as it is relatively easy to do.
Timing chain: I had this replaced 15000 miles ago.
Clogged injectors: Trying to figure out how to clean these from the Hanes manual.

Any other ideas would be a big help. Thanks in advance to those of you that patiently read through this lengthy post.

 

#1 Read the codes again.

#2 Post them for us.

#3 You should have a timing belt, not a chain??

#4 Is unhooking the battery the correct way to clear codes from a 2001? I thought the newer models may have to have a special procedure done to permanently clear codes?

#5 I am not familiar with VTSC and TRAC. Are these alarms based on an automatic traction control transfer case system? If so, could the transmission be not shifting out of high gear when you come off the interstate and be killing the motor?

#6 I have had the problems you mention because fo induction leaks- on the 22RTE engine the intake was loose at the turbo inlet and the elbow into the manifold was badly cracked open- both equal the AFM or MAF not getting the correct air draw through it.

 

#1 I'll get the codes again, unfortunately it won't be until tomorrow when the guy with the scanner comes over (the 4runner is my only ride).

#3 I do have a timing belt - I was just reading straight out of the Hanes which covers the Tacome, T100 and the 4runner.

#4 I am not sure of the correct method for clearing codes. I assumed this is what the mechanic did the first time because when I unhooked the battery cables (I remember now that I unhooked both cables because I cleaned the terminals) the radio was reset and the check engine lights were gone.

#5 Interesting....thinking about this one...I was thinking it was a fuel flow issue but I am not so sure now - I remember now that I revved the engine while in park to around 2500 rpm. If there is a fuel-flow-to-the-engine problem at any point in the lines, with the injectors, anywhere, should I be able to rev the engine like that? On the face of it it seems that if there was a fuel flow issue it wouldn't matter wether or not the car was in gear. If this is true, then it seems like a transmission problem, and your suggestion is interesting. In this case if it is a transmission problem, I am hoping is with one of the many sensers and not something wrong with the actual transmission.
#6 I looked at all the hoses, and I hear no leaks and see no obvious cracks anywhere, although I am not sure how well I would be able to hear a leak with just my ears while the engine is running. I could clean the MAF again and replace the air filter. An easy fix but I am skeptical about this causing the problem.

 

that kinda does sound like a tranny problem. if its in high gear all the time then it will indeed stall it out. you might could try revving it and putting it in gear. i dont know if that will screw anything up or not though. ive done it in a manual tranny car to do a burnout or something. not with an auto though. if you do try that, make sure you have some room in front of you to work with. like, dont do it in the driveway. will it go into neutral and idle?

 

It idles in nuetral and park alright, maybe with a little roughness there that didn't seem to be there before....I thought about trying to rev it and quickly putting it in gear but I don't want to cause any damage....I'm not sure if it would cause damage, just hate to take that chance and still not be any closer to diagnosing the actual problem....

 

Long shot but when did you get gas last. I got bad gas last week. Mine started idling low and wouldnt crank once. I changed the fuel filter, plugs and wires helped some. After i ran that tank out and about 1/4 of the nxt it cleared up.

 

That was suggested to me. I got gas probably a week ago now at the Hess station close to me....yea I remember because the tank was on empty and I try not to do that, makes sense too because I usually fill up once every two weeks when driving to my usual destinations and the tank is a little over half full....just found the receipt too....probably could change the wires and plugs anyway, need to check that out, not sure why that would effect anything though...

But yea, I just replaced the fuel filter, which I should've done 15000 miles ago probably, with no change - cranks and idles alright but immediately dies when put in any gear...I was going to check the fuel pressure after I find a "schrader" fitting on the fuel line in the engine compartment...I was also told to tap on the gas tank - not sure what this would do....does anyone know off-hand what the fuel pressure should be for my 4runner (ha ha)? I was going to try to look it up of course, just wanted to make sure no one is out there with that bit of info just bouncing around in their head...

but

 

Oh, hooked up the scanner and the error code was 01991 (if I remember correctly), which translated into "lean mixture"....this seems to point to a fuel flow problem...enough air, not enough fuel...at least that is what I am thinking at this point...still perplexed as to why it ran fine (at least, it seemed to run fine with no noticeable decrease in power) with that error going off for many months and then all of a sudden something happens....

 

if its not your maf, then its probably your a/f sensor. if you have had those lights on for months then it was probably your a/f sensor telling you it was dying...now, its pretty damn dead



https://www.yotatech.com/forums/f2/h...riving-112372/
https://www.yotatech.com/forums/f2/c...d-i-do-134290/

 

Also I have heard of Torque converters staying locked up instead of locking up only while moving. If this happens well- its like dumping the clutch too fast in a manual. So every time you put it in gear it dies. Try putting the transfer case in Neutral (I hope you have a neutral) and then see if it still dies when you put it in gear.

DO NOT rev the engine up high and drop it in gear in an automatic. You will cause Transmission damage.

What is the idle speed? Also, unhook the vacuum to your EGR valve. if it is stuck open it may cause the engine to stumble under ANY load.

 

torque converter.....I don't mean to sound like an ignoramous but I am going to have to look that one up....I am assuming this is a circular component, possibly between the engine and the transmission?...it sounds like I would much rather have a bad air/fuel sensor! (gotta look that one up too)....hopefully an a/f sensor isn't too hard to get to and too expensive...the a/f sensor makes sense and seems like a good place for me to start today.....
idle speed was pretty high last night when I was messing with it, probably around 1000 or more, I was assuming it was high because it was chilly and the car never got up to normal operating temperature....I will try unhooking the vacuum to the EGR valve and see what that does...

 

just called the dealer and the guy I talked to agreed that it sounded like an a/f sensor...they are $236 apiece and there are 4 or them! However, he also said that the OBDII code number would point to the one, or ones, that are bad, so I was going to make sure of the number....how am I going to know, though, which one the code is referring to? The sensor comes with a booklet but I am skeptical about it having vehicle specific info in it like which out of 4 a/f sensors is the bad one, or ones. gotta get my friend to come back over, ...I am thinking I need to buy my own scanner...

Are these sensors hard to get to? And, is it possible to simply do some maintenance to them and get them sensing like normal again? I was going to look at the Hanes again to see where they are and if it says how to mess with them....the guy at the dealer said it would be around $400 including the part and labor! Ug

 

OBDII trouble code is P0171

I'm having trouble finding the a/f sensor - I don't see it in the Hanes manual

 

Just paste P0171 into the search feature and read away. Your a/f is underneath and is the "equivalent" of O2 sensors. You should have them before and after the cat.

 

Oh, when you say a/f sensor you mean the 4 O2 sensors underneath the car...explains why I couldn't find an a/f sensor (ha ha)...ok...so, I know where those are...if I can figure out which one is bad (the guy at the dealership said they can tell by the code...I wonder if there is a way to just fix it, depending on how its damaged of course, rather than pay a couple hundred bucks for one? I appreciate the help by the way.

 

actually looks like there are only 2 O2 sensors, one before and one after the catalytic converter....I read some more of the P0171 threads...sounds like a common error code...I am cleaning the MAF again to see if it fixes it, along with pulling the EFI fuse to clear the code from the computer to see if it comes back after I put the cleaned MAF in.

 

I cleaned the MAF and pulled the EFI fuse to no avail. No dash lights but it still dies - very abruptly - when put in gear.

I found this artical "Tech: Understanding OBDII Engine Systems and Fuel Mixture Control" at 4x4 wire.

Trouble areas:
Air Induction System Leak - not sure about this one yet, seems unlikely too
Injector Blockage - seems unlikely
Mass Air Flow Meter - I just cleaned this
Engine Coolant Temperature Sensor - ?
Fuel Pressure - this is starting to look more and more likely
Gas Leakage from the Exhaust System - I'm not seeing any leaks whatsoever
Open or Short in the Oxygen Sensor or associated wiring - ?
Oxygen Sensor Defective - ?
Engine Control Unit - ?

 

I would do check the following...Check your intake boots for looseness/cracking,clean your IAC valve,double check your crank pulley bolt is tight...

 

so it is turning out to be something wrong with the transmission. i had it towed to the dealer, they found a loose wire, told me they fixed it, I drove off, and it does the same thing. had it towed back to the dealer, the mechanic scratches his head and speculates about the torque converter. I leave and tell them to let me know. they call and they describe the problem as something similiar to what happens when you leave a manual in gear and the car comes to a stop and the engine stalls. all they can do is replace the entire transmission, the service manager tells me, for the price of $3000+/-!! then they try to charge me for the 2nd tow. i managed to back them off of that ridiculus idea (charging me for the 2nd tow) and arrange it to be serviced at a transmission place, which is where it is now. I'm not even sure if the dealer tried to diagnose the specific problem or if they just gave up and proposed the easiest, and most expensive, solution. My friend's saleen mustang's new transmission didn't even cost that much!!! so now I am waiting, hoping these guys know what they are doing and can fix the problem. in the meantime I am trying to find some exploded drawings of the transmission and related parts to my car so I will have a better idea of what the transmission guy is talking about when he calls me back today - I found a few but none yet of my specific model. The hanes has something but not sure what I am looking at. At any rate, I am still sweating over the prospect of paying several thousand dollars...I was told by a mechanic friend of mine that works for another dealer that some friends of his work for a toyota service center and he said he learned they have a specific policy to just outright replace something instead of fixing it. so, if they are doing that to me, screw them. no offense to anyone that works for toyota but that is shady if that is indeed the case.

For those curious enough to have read through this thread I will post the ultimate diagnosis, which I am hoping is significantly better than the dealer's.

 

Are you able to keep it running in gear at all?
Can you kinda feather the gas once its in gear and keep it running. Dont dump it in gear but try to get in in with higer idle then brake and gas it to keep it running. Have you been able to run your last tank of fuel out and get fresh fuel? Im stil stuck on something simple like bad gas.
Unless it just shuts down like a key switching it off.