igogusto

Took off the TB and cleaned it, and cleaned the IAC, it had a lot of carbon build up!!! I was real careful with using carb cleaner to clean it. Bolted it all back together and it fired right up. It seems to be running a lot better. It has a lot better throttle response and the idle seems to be a little higher and is not stuttering. I gave it WOT on the road and it did not die on me like before, but this problem has be intermittent.

I hope that that stalling problem is fixed. I will run it for a while and let you guys know the status.

Mechanically it was simple to remove and re-install the TB, it was much harder to clean it. So to all you guys out there that have not done it, do it.

If the 4Runner runs good for the next few weeks, I think that it is time for the Deckplate Mod!!!!

Thanks a million for your guys' help!!!! If the problem is fixed, you all saved me a costly trip to the "stealership". To all of you that helped me on this project: If you are in my neck of the woods someday, let me know, and the beer is on me!!!

Cheers! (_)3

Geoff.

creekfisher

WOW. . . partznet.com lists retail as $3.92 and $3.46. I paid $3.06 and $2.70. Usually, my dealer is close partznet.com's retail prices.

Thanks for the report.

creekfisher

OK, I did it.

About 7,000 miles ago I cleaned the TB without taking it off. Now that I have cleaned the TB both ways, I won't clean it without removing it again. The hardest part is removing the hose clamps from the IAC. Is there a special hose clamp tool? If so, please tell me about it so I can buy one!!

Since I had the TB/IAC off I decided to repalce the plugs too. After cleaning the TB and the IAC and replacing the plugs the 4runner is running very smooth. I replaced the PCV valve too.

Bottom line - I think removing the TB is the better way to clean it. Plus, it allows you to clean the IAC too. I think I'll do this every 30,000 miles when I replace the plugs.

ToyotaVirginiaGuy

When cleaning the IAC it would be a good idea to replace the PCV valve too. Also on the newer models that do not have a wire to the throttle body disconnect the battery for a few minutes. The computer must relearn how to idle properly now that the system is clean. Hope this helps someone.

Alpine114

Experiencing some similar problems with my 1999 4runner 3.4 but also some other interesting ones. Background: My 4runner had a CEL on for a while, and one day i was driving it, the engine starting making a loud ticking sound, and needless to say, i should have stopped driving there instead of attempting to get it home. Ended up blowing up a loose spark plug. Had the mechanic tap and die new threads in, and it ran well after. I was still getting sub par mpg, around 11, and my cel was still on. So I finally decided to cough up the money to replace timing belt, water pump, and to address the CEL. $1000.00 later, they replaced rear O2 sensor, TPS, Timing belt, Water Pump, Thermostat. Drove it 2 miles from mechanic, cel came back on, and chugging at 2000-3000 rpms...but not below or above, its a manual transmission btw. Also, usually it idles around 750 rpms, now around 1500+. Codes read as insufficient coolant temp( i didn't replace coolant temp sensor, but if i unplugged it, the idle dropped back down to 750rpms, if this means anything) and i forget the other code number, but suggested toward Front O2 sensor. I bought a new denso O2 sensor for front, installed it, and managed to get light off after battery reset, but still same symptoms.....high idle, and jerking/chugging at 2000-3000 rpms... Also in the past, i have cleaned the throttle body, and had a new MAF sensor. Took it to stealership last week, and they think its the IAC. Is it possible that once the mechanic changed out the tps, O2, etc that those parts were actually masking the chugging/jerking problem, and once they were fixed, it wasnt getting the same accelerated fuel supply or whatever as before,or is that just crazy talk?...frustrated and in need of suggestions. thanks in advance.