I am having an issue with my 4runner. When I am at idle it feels like there is a miss and it stumbles. If I give it even 2-300 more rpm it goes away. It does it worse when cold. Sometimes it feels like it's going to die but the rpms are still at about 7-800. I have taken the throttle body off and cleaned it and the iac. I have replaced the plugs, wires, and air filter. You can hear the (miss) through the air box as a loud unstable hiss. I will be replacing the fuel filter but I doubt it is causing this issue.

 

just for added info whats the mileage and what brands of parts did you use?

oh and you sure you screwed the plugs in correctly? just curious

 

I used ngk plugs, Toyota wires, and a fram ir filter. The engine has about 20,000 on the rebuild.

 

When it does this at night you can see the dash/headlights flicker.

 

its electrical, well narrowed that down. time for beer lol

 

I was thinking maybe a coil and the flickering would be like if it was idleing really low and about to die, don't know if it IS electrical.

 

its probably not man i was kind of kidding. hopefully someone will chime in here. sorry to waste your time

 

Is your alternator charging? 14V+ ?

 

Yeah, it's charging just fine It gets a little better when I turn on the front defroster and the idle goes up but it's still there. You can see the shifter move.

 

pull out the MAF


spray in some CRC MAF cleaner

make sure the little wires are nice and shiny

spray more in to be sure, also hit the temp probe part


re-installed

unhook ecu fuse for 10 minutes so it will
reprogram all it's trim levels


you may be good to go at this point

the design of the intake air system makes particles settle on the MAF
and this is the cheapest and easiest thing to just clean and eliminate
as part of any hesitation or idle problem like you describe. 3 bucks for
a can of spray to clean a part which commonly gets fouled. it has to do with
when you turn the engine off, pcv and other gasses just swirl and
settle in the tunnel....eventually MAF gets some build-up.

you have to use MAF spray, or carb cleaner which specifically states no residue
left behind. Chem-Tool is one, and now CRC makes a MAF specific type


lights going low is just a result of the rpm drop

 

Stoopid Question.....

You DID use dual electrode plugs ...right?

 

Yes, dual electrode. I also forgot to say that I just bought a new mass airflow sensor as my last one was shot. It's about 3 months old but the truck was doing this before the new one.

 

ok then... you can then unsee what I wrote

what are you getting for OBD II codes, if any DTC, and what are the I/M readiness readings ?

 

Could be a bad ground. Check to see if the engind Ground is clean. You can also run a 2nd ground from your battery to the rig. This did help my idle quite a bit as I had the same problem your having.

 

No codes. I will look at the ground tonight.

 

Ok, here'an update. I replaced my fuel filter a few days ago and it seemed to run a little better. The next day I made a 650 mile road trip to Idaho. While I was here the check engine light came on. I went to Autozone and got the codes, P0300. I got a P0306 a couple of months ago after changine the plugs and wires but I cleared it to see if it would come back and it never did. Now today I cleared it at Autozone and it stayed off for a couple of hours but as I was sitting at an idle it popped back up. Now tomorrow I have to make the trip back home where I will dive into it more, checking injectors, grounds. I have run seafoam through it with no change.

 

i know this sounds elementary but did you reset your computer?

 

them be misfire codes and they are pretty specific

misfire
and misfire on cylinder 6

go through your ignition system soup-to-nuts

 

I know they are misfire codes. I had a P0305 too when I got home. I just got home and whe I pulled into my town it was chugging really bad and when I got home I noticed a small knock at 1400 rpm. Sounds like it's coming from the front of the driverside head. I am pissed and am taking it to the dealer tomorrow. I hope it's not major but, I know it will be.