Jay351

First off, I have done a good amount of searching, but I have yet to get the answer I need. I really didn't want to post this, but I need to fix this problem.

For the past year or so I have been having an issue with my idle. If I were to leave the truck to idle for a period of time, the idle will slowy drop till it bearly stays running at 200rpm. If I were to drive on the hwy at 3,000rpm for a long period of time my idle would now sit at around 1100rpm.
Recently I went wheeling, the truck stayed in 1st gear and 4low pretty much the whole time, rpms ranging from 1000-1500rpm (for the most part). By the middle of the day my idle was down to 500rpm. Near the end of the day the idle decreased to 200rpm! It did not want to keep going. On the drive home the idle improved to 400rpm, but that is still WAY to low.

Some people I have talked to seem to think the o2 sensor can cause this idle problem. My current o2 sensor is pretty darn old (over 100k on it, and a blown hg), I have a replacement but since the original hardware is welded on, I cant remove it! How high up on the list should this repair be?

Recently I read up on the TPS, I know mine is old, I don't have the proper tools to check it out. Anyone think this could be contributing to this? I hear they can cause proplems similar to this...

Thanks for any help you guys can offer!

904_runner

My advice will be finding the problem through elimination.

First off check the tps sensor! Mine was doing that, it didn't really change that drastically but it might go between 500-800 rpms at idle. I replaced mine and it solved the problem. (now mine is running weird, not sure how to describe it other than it seems slugglish then all of a sudden it will go, i m in the same boat as far as elimination. I hoping changing the plugs might help. Sorry off the threadjack)

Jay, you can search, there was a thread like "changed the tps excellent results" or something like that and people talked about the problems of the tps sensor being out of adjustment.

I know 4crawler has a link on his page about how to adjust it

just a 22re

you should clean out and check the idle air controller that bad boy would be giving you the problems you are seeing!

Jay351

I saw that thread, thats what got me thinking it was the TPS in the first place! I guess I should just go buy the damn tool so I can test this sob.

I had the same issue with the sluggish then go, I replaced my plug wires (NGK performance wires) and replaced my leaky intake hose (ISR) and it cured the problem.


And where would I find that little guy?



Thanks for the help guys

904_runner

[QUOTE=Jay351;50891677]I saw that thread, thats what got me thinking it was the TPS in the first place! I guess I should just go buy the damn tool so I can test this sob.

I had the same issue with the sluggish then go, I replaced my plug wires (NGK performance wires) and replaced my leaky intake hose (ISR) and it cured the problem.


Dammit, i just changed the wires to belden (was on it before, and i didn't have the money to get ngk or denso) But it was fine until recently.

Therefore im hoping its the plugs, i haven't changed them, looked new when i bought the truck, i know i should have so ill change the plugs when i get home (been 10,000 miles since i got the 4runner)

Theres an idle screw or something like that, but i have never messed with it

just a 22re

eww um i know were it is on the 22re but on the 3.o um maybe same?

http://www.autozone.com/selectedZip,.../selectZip.htm

this is what yours looks like so it should be round on the TB and have a plug on it i would think

Jay351

[QUOTE=904_runner;50891682]www.sparkplugs.com My NGK's were CHEAAAAAP!!

Hmm, I guess I will take a peek at the 93 FSM. Thanks

Team420

The iac is on the t.b.... If you suspect the tps... unplug it and drive around for a few miles...if the tps is bad, the when u unplug it, you will idle high, but consistent.

Jay351

Thanks team420, I will try unplugging the tps.

Team420

np... also... are you 100% sure you dont have a vacuum leak? that would also cause those symptoms.

Jay351

Im pretty darn sure I dont. We replaced a few lines when we did my EGR work, I couldnt see any lines that were leaking. Any particular lines that might cause this?

Team420

na... no specific lines I can think of... I know that I had the code 71 for a long time, and I am 100% sure it was a vacuum leak, but I never could find it... so I did the next best thing.... block off the egr all together. she idles a lot better now too.

904_runner

^^^ I had that code because the egr temp sensor wasn't working. I now have a part from a non-California truck where it tricks the computer to thinking it is at the right temp all the time

Team420

Ya... a $0.24 10 ohm resistor...lol... had to do that after I blocked it off

Jay351

Im lucky, my EGR does not have the sensor Though I had to have it in perfect condition to pass smog (which I proudly did with flying colours!).

Team420

no smog here.... cat will be gutted soon too

Jay351

Haha, hi-flow cat ftw

So what will the TPS do, if I uplug it and drive around and its good?

904_runner

don't know what to tell you, mine ran fine with out the tps connected (only for a few minutes untill i noticed it wasn't connected) i didn't drive it around though, it will probably trigger a tps CEL if you drive it around would be my guess, i guess it is a process of elimination, if nothing changes then it is probably not the problem!

Thats my guess

Jay351

Okay, well I unplugged the TPS and started the truck, took a few seconds to get it to start but once it did it jumped to 1500rpm. I plugged the TPS back in and the idle dropped to 1100rpm. Keep in mind the engine was cold (starting to warm up).

What do you think guys?

904_runner

IDK, i say do the test once its warm. (not even sure what the test is at the moment, im sooo tired)