Idle jumping and dropping 550-900
- Thread starter Arnezie
- Start date
New plugs. Came across this , anyone know what this means ?
If I had to guess, I'd say the plug wasn't tight and was leaking combustion gasses by the compression ring and up the tube. Had that happen to my 98 Tacoma. It had a slight miss.
I was able to remove the IAC without damaging the gasket, so I did not replace it when I serviced mine.
Arnezie
New member
Thanks , that could be it none this one was finger tight if that. Didn't have time to do the IAC tonight but going to do it in the very near future. Maybe ill get a gasket to have on hand just incase.
LittleCaesar
New member
Arnezie, are the plug wires original?
The plugs aren’t bad but needed to be changed. Don’t forget to gap them. As [MENTION=92690]Riceye[/MENTION] said, a loose plug could cause a slight misfire, even more apparent under load as when the AC is on.
The plugs aren’t bad but needed to be changed. Don’t forget to gap them. As [MENTION=92690]Riceye[/MENTION] said, a loose plug could cause a slight misfire, even more apparent under load as when the AC is on.
Arnezie
New member
No they are 50,000 miles old
And I replaced the plugs with the cheaper ones copper not platinum that you suggested.
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The proper plug is the NGK 3967 (BKR5EKB-11) or Denso 3194 (K16TR11) which are not platinum, but are dual electrode. The dual electrode type is very important. Don't even bother with anything else. Either the NGK or Denso that I listed, but nothing else.
DaMonkey
New member
First thing to look for is if any one of the plugs is different from the others. Take a look at upper middle plug. the carbon buildup around the hex and also there is a black collar just up the ceramic up to where the boot covers it. None of the other plugs have that. I think Riceye is on the right track, it was not tightened down. Hopefully it's that simple, but that plug definitely is different.
Other than that, there does not seem to be fouling or erosion or oil on them. I'd definitely try your new plugs and see if idle smooths out.
Other than that, there does not seem to be fouling or erosion or oil on them. I'd definitely try your new plugs and see if idle smooths out.
DaMonkey
New member
this one will be easy to chase down because it just happened. most likely vacuum leak, maybe left hose off? how are hose conditions?
or what heat mentioned, that issue about TB not shutting, seems shaft develops some play over time.
you'll get it...
Like others have stated, make sure you didn't pinch a gasket or something. But if everything is done correctly,how dirty was the IAC? If it was really bad and you cleaned it really well then it could be the ECM hasn't had time to re-learn all the extra air it is getting into the system.
When throttle body/IAC have lots of carbon build up they dont allow as much air to flow, and the ECM learns how much air it is receiving. Once you clean it the throttle body or IAC allows much more air to flow and then the ECM sees all this extra air that it isn't use to so it has a high idle. You could either just drive it around till it re-learns itself, or disconnect the battery for a few minutes and that will clear the system memory.
Arnezie
New member
It seems to be better now, I manually throttled up and down under the hood and it’s like the throttle wasn’t fully returning , I also just disconnected the neg terminal like was suggested and it seems better. What a pain. Now hopefully tomorrow when it’s nice and hot I’ll be able to see if it has cured the erratic idle. Thanks everyone so far that’s chimed in.
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