99silverunner

I have a 99 4runner with the 5vz-fe 3.4 v6

After doing some research on hard warm restarts, which I had been experiences slightly I figured I would go ahead and clean the throttle body and the IAC while I had the time

Before doing this I disconnected the battery and pulled the EFI relay to reset the computer

After getting everything cleaned and back together I took it for a test drive. The idle used to be 700 rpm when warm and parked.

When I started it up this time the idle started out at 1800 rpm cold up to 2200-2300 rpm within a minute or so.

After driving it down the street and back to get it warmed up the idle is now pulsating from about 1500 to 2500 rpm or so.

Is this normal? If not what should I check?

I was trying to make the thing run better and ended up making it run worse

Any help will be much appreciated!

ToyoTech559

Did u disconnect any coolant lines. If so you might need to get the air out of the coolant system. If that's good. Disconnect the battery for a few mins than reconnect. Start vehicle up and let it idle till warmed up. Oh check for vacumn leaks

99silverunner

Yes, I completely removed the throttle body to clean it and clean the IAC. There were two small coolant lines on the bottom of the throttle body and two or three vacuum lines.

Like I said I disconnected the battery and the efi relay so I figured it had something to do with relearning the tune

It idled great before so I I'll try to bleed the lines on the bottom of the throttle body and see where that gets me. Thanks for the tip and I'll let you know if it works

rworegon

Be sure there are no vacuum leaks in the hoses or between the throttle body and the upper intake plenum.

99silverunner

I'm gonna check it out in the morning, thanks for the tips.

I forgot to say that prior to cleaning the TB and IAC, when it was idling perfect I replaced the fuel filter, plugs, wires, seafoamed it, new pcv valve, cleaned MAF with CRC, and changed the oil.

I drove it yesterday and this morning and it was running great. I was just trying to make it run alittle better by cleaning the IAC since it has 160k and I'm sure it has never been cleaned before

On bleeding the lines on the TB should I have the engine running and pull one off at a time or will that just make a huge mess? Any suggestions?

Thanks

rworegon

I've never worried about bleeding those coolant hoses under the throttle body....not sure how one would go about it. Pop the radiator cap off while the engine is cold, let it idle until it reaches operating temp and any trapped air should escape.

Any electrical connections loose in the area you were working?

ToyoTech559

Yea I would just pop the cap off when cold and let it idle till warmed up and add coolant if needed before capping it.

99silverunner

Ok guys I think I got it fixed this morning

First thing I did was track down all vacuum lines in the area, all were good

Then I pulled off the radiator cap and started her up. After doing this I thought it was gonna fix it as the rpms started around 1300 but then they climbed to 2000+

I read about every article I could last night about this so I decided to pull the intake tube off and remove the two screws that hold the IAC solenoid on to the TB. I had removed this when cleaning to move the valve side to side to clean it better

When I installed it I used some ultra blue rtv to seal it up, a small amount but probably not small enough.

THE PROBABLE FIX: I removed the IAC solenoid, removed any gasket material even close to the valve pin (I guess thats what that little magnet can be called) and I also sprayed a little PB blaster on it.

The valve moves so much easier now when I sprayed the PB on it!!!

I cranked it up and walaah!! She was idling at 900 rpm or so, I'm about to take it on a 20 minute trip to work so by then she should be down to 750. I'll let you all know if this solved it but I"m pretty sure it did

99silverunner

PROBLEM IS FIXED!!!

After driving it about 20 miles total the idle finally calmed down to 750 or so when parked

Its crazy to think something that small can mess with the idle so bad but at least I know now

Lesson learned: When cleaning the TB make sure the IAC valve moves easily before putting it all back together and if you have a problem check it again!!

ToyoTech559

Nice glad it's fixed