Rough idle when not warmed up

[4runneracerunner]

So i have a 1995 4runner 3.slow and it runs super great on the gas, but when i start to slow down to a complete stop it idles, like the RMPs jump down then jump up to 600 and back to 250, and wont stop, unless i go on the gas, but once i drive for around 1 mile non stop, it will stop idling rough, it will idle just right and smooth, any ides? i have a K&N intake, i replaced plugs and wires, cap, fuel flitter and timing is on right, i replaced TPS, i dont understad, any help with help. no vaccum leaks

thank you

 

[Yotaknowsbest]

So i have a 1995 4runner 3.slow and it runs super great on the gas, but when i start to slow down to a complete stop it idles, like the RMPs jump down then jump up to 600 and back to 250, and wont stop, unless i go on the gas, but once i drive for around 1 mile non stop, it will stop idling rough, it will idle just right and smooth, any ides? i have a K&N intake, i replaced plugs and wires, cap, fuel flitter and timing is on right, i replaced TPS, i dont understad, any help with help. no vaccum leaks

thank you

Having the same issue with mine (1992 4x4). Started the last time I took it up the hill from Phoenix to Flagstaff. I'm no mechanic, but I was going to look into either a vacuum leak or O2 sensor. Would also like some info on this issue though.

Thanks

P.S. My rough idle doesn't stop after she's warmed up, but like racerrunner mentioned, it's smooth sailing with your foot on the gas.

 

[4runneracerunner]

Yea it's werid, I replaced all of mine vaccum lines, o2 sensors and my Mass air Flow Meter, so I don't understand, let me know when you firgure it out

 

[Hyde802]

Did you adjust the TPS correctly when you replaced it?

 

[4runneracerunner]

Yes I did, it wouldn't pass smog unless that was adjusted right, so yes it is

 

[crash813]

TPS setup is super tricky, you have to have gauge feelers and a multimeter! If its only happening when its cold, you might want to verify you have no air trapped in the coolant line and/or the small line running into the TB is not plugged. Also, check your ect. O2 sensor isn't reference until the engine reaches operating temps.

Other things to look for is properly working cold start injector.

After that, its looking at all kinds of stuff including stuff you just changed.

 

[NobleShield]

So i have a 1995 4runner 3.slow and it runs super great on the gas, but when i start to slow down to a complete stop it idles, like the RMPs jump down then jump up to 600 and back to 250, and wont stop, unless i go on the gas, but once i drive for around 1 mile non stop, it will stop idling rough, it will idle just right and smooth, any ides? i have a K&N intake, i replaced plugs and wires, cap, fuel flitter and timing is on right, i replaced TPS, i dont understad, any help with help. no vaccum leaks

thank you

I also have a 95 3.slooooooow and have had the same symptoms, sluggish idle dipping between 250 and 750 but with a check engine light. It also goes away for me rather quickly. I did the diagnostic thingy and got 21 (O2 signal). Have not had the tine to replace the sensor yet. Hope that helps narrow it down a little.

 

[4runneracerunner]

I don't have any check engine light on, and I replaced both of my o2 sensors

 

[Yotaknowsbest]

TPS setup is super tricky, you have to have gauge feelers and a multimeter! If its only happening when its cold, you might want to verify you have no air trapped in the coolant line and/or the small line running into the TB is not plugged. Also, check your ect. O2 sensor isn't reference until the engine reaches operating temps.

Other things to look for is properly working cold start injector.

After that, its looking at all kinds of stuff including stuff you just changed.

It does seem like it takes a few minutes to start acting up. I'll check the engine temp.

 

[4runneracerunner]

Iv replaced the coolent temp sensior around a month ago

 

[Metalguy]

Mine is acting exactly like Nobleshield's symptoms. My check engine light just came on, and it was doing it before that came on. I haven't had a chance to do the diagnostic yet. -------Metalguy

 

[4runneracerunner]

Let me know if you find out what it is