Correct idle RPM?

Anyone know what the proper RPM range is at idle and a 2000 3.4 Prerunner? Mine seems to raise and lower down to around 400 where it struggles to stay alive. Any ideas?

 

Maybe you need new plugs. Possibly a faulty injector? Bad gas? Just some ideas.

 

Try unhooking your battery for 15 mins then hook it up and start

 

This was recently done when i did my steering wheel swap. Nothing changed. Thanks tho

 

Mine idles around 750 when fully warmed up and around 1100 with AC on while warmed up. If you have an auto it'll be closer to 650 warmed up and in drive.

 

It is an auto. Seems to bounce between 400 and 700 and turning the AC off doesnt seem to bring it back up enough. Sometimes it drops low enough to BARELY stay alive. I have had a code come up for running lean. I just ordered plugs, boots and wires so ill see what that will do.

 

has the throttle body ever been cleaned? There is an air gap around the throttle blade/ throttle bore that needs to be maintained and when it gets coated in gunk it will act like what you are describing... check the PCV valve while you are at it, if the rubber that holds the PCV valve in the valve cover is hard you are going to have to make a command decision, will I get lucky and not have it break into bits and fall into the valve cover / PCV pocket or will it come out in 1 piece.

 

I did a seafoam intake clean about 20k miles ago. That cleaned the throttle body better than i thought it would've. It also fixed my stalling after stopping right after a hard acceleration issue. The PCV valve has probably never been touched.

Edit: just ordered the PCV valve and grommet. Thanks for the heads up

 

How long ago? Have all the DTC Readiness monitors returned to green? I disconnected my battery for an extended period while working on some electrical. Didn't connect at first but I realized my idle was 'off' when I would start up. Was about to plan on throttle body cleaning, Idle Air Control cleaning - all the usual suspects when I realized, wait a minute - damn computer is showing red/incomplete on the DTC. Wouldn't you know it, as soon as I drove it long enough for it to clear/pass - idle issues were gone.

Oh and I just finished replacing my fan clutch (didn't do it when water pump was replaced) and even though it passed the typical tests it was still original and with 150k+, time to change it out. Damn if it hasn't brought that roar back to life when cold starting. Idle is spot on.

 

Its been doing this for awhile, probably 40k miles. Only codes that tend to continue to show up are running lean and o2 codes. I cleaned the upstream o2 sensor yesterday hoping it fixed the codes.

 

This happened with mine. I replaced the IAVC as it was stuck closed.

 

Whatd that cost ya?

 

I purchased the part for about 20 bucks on ebay. Having a mechanic do it will cost like a few hundred probably. You can try picking up throttle body or carb cleaner from an auto parts store and cleaning the carbon out of yours and it may unstick it. Google/youtube which type of cleaner you need as some of them will damage the electronics in the valve. If you do the repair your self you probably will want to use pb blaster and a good screwdriver on the IACV screws as they are probably stuck so you don't strip them.

RPM for the Tacoma 3.4 in the factory service manual is 700 plus or minus 50. In the manual it state if rpm is not this to check the IACV and air induction system. It probably stalls because its not getting enough air from the IACV. Does it have a check engine light? If you dump the code yourself or go to autozone or another auto parts store where they will do it for free I will beable to give more accurate info.

If its 100k plus miles the IACV is probably coated in carbon which is making it stick closed. Mine had a thick layer of black carbon and i'm at 130k miles.

 

Its been popping a "Lean" code. Screw it. I just ordered a new IACV. Truck has 185k miles on it and id bet the iacv has never been touched. This weekend i will be doing plugs, wires, boots, PCV valve and grommet, and now the IACV. Thanks for the help!

 

No problem, at 185k Miles its probably definitely gone. Good deal not going to a mechanic for all those things. Feels like a rip off every time I end up there for these stupid problems and they never even fix it. Check engine light just comes back on and the car stalls within a week on a major street packed with cars usually =(. Also cost like $300 bucks for parts and labor to a $20 part and a half hours work. I replaced IACV and it went up like 300 RPM and has never gotten close to stalling after. Watch out for coolant dripping when you unplug the IACV hoses and do it when the engine is cold. If the engine is hot a lot of hot coolant will spray out. Wearing eye protection is a good idea. I have done it cold and not much came out. Maybe do it over dirt/not your driveway or have a towel to catch the coolant. It doesn't drip a lot if engine is cold and if you keep the hoses elevated it might not even drip any. It advises in the manual to drain coolant but I had only like a table spoon come out however that might not always be the case.

Not sure about yours but after I did my IACV my O2 sensor bank 1 sensor 1 was gone reading 3 volts instead of .9 volts. I haven't replaced the part yet but I'm almost certain it's bad with that reading. I'm waiting for the part to come in a week but if you want to check yours you just need an obdII scanner with live data. They're like 40 bucks on ebay if you search obd tester. They're also useful for a lot of other things to make sure everything is running correctly within the car.

Edit: O2 sensor turned out to be an A/F sensor even though my obdII live data was calling it an O2 sensor. This means 3 volts is correct for that.

 

Yea mine usually stalls right after i have a... "Confrontation" hahaha hard acceleration and then come up to a stop light, usually right in front of the guy i just blew by haha
As for the coolant, ill probably just pinch the tube.
For the most part I can get everything done on my own. So far the only time ive had to go to a shop was for a tranny rebuild *knock on wood* thanks for help man, ill try to update after i install everything

 

Make sure when you unplug the hoses from the IACV that the engine is completely cold and maybe wear goggles/eye protection. If the engine is warm it will spray a lot of hot coolant out. It could still have pressure also so prob wear eye protection just in case.

I ended up having a p0505 high idle with the new part as it wasn't the same part. It fixed the stalling however idle was 100 rpm too high. The part looked completely identical however when I took it apart the inside was not the same. I just ended up cleaning my original part and it brought the idle back to normal and got rid of the p0505 high idle.

Maybe use a live scanning tool to check idle also because the marks on the dashboard are not that accurate.

The part also has an adjust for the cars idle. It's the two screws that are elongated which are not the part that has the connector. You twist them and it changes the idle. So maybe set them in the way your original part is. If its throws a p0505 or rpm is incorrect in a live data tool readjust the idle that way. If it's not an oem or correct part it will have the elongated screws however they will not adjust the idle because its cheap Chinese crap. The screws are there however there is nothing on the inside that actually moves when you twist the cover =(.

 

Just finished putting on new IAC VALVE, PCV VALVE, SPARK PLUGS BOOTS AND WIRES. Happy to say my idle is now perfect. The PCV was okay, the grommet had turned to plastic though. Old Spark plugs, wires and boots all looked okay. But IAC... Ohh the IAC... carbon build up was extreme. The o-ring fell apart in my hand. And valve was 99% stuck. The carbon had built up a wall that extended between the throttle body and the IAC body. Also almost all the hoses I had to touch looked pretty bad. Trimmed up what i could and reinstalled with o-ring lube. (Gonna look into finding a hose kit hopefully). After installing everything the idle is perfect. Started the truck and it revved at 2 grand for 5 seconds and then calmed down to a happy and "ready" 700. Ill attached pictures soon. Just wanted to update and thank you guys!

 

Yea i battled that for like two years spending wasted money at the mechanic. Till I found out my iacv looked like that. My car was throwing a p0171 and it really doesnt state the iacv in a whole lot of places.