Hi, I'm pretty new here and have searched for this answer but couldn't come up with anything - and am also new to working on vehicles.

After doing a spark plug and wire change (properly gaped) I noticed a high idle RPM. After a few miles of driving - idle resumed to normal as if nothing was wrong. Being a tad suspicious I looked for anything that I may have accidentally disconnected (vacuum line, etc) and noticed this hose. Its not the one from the evap can.

Here's a photo (3 photos actually - 2 from the top and 1 from the bottom). I've circled the "mystery area".



(if this image fails to display properly, I'll make an edit)

Any help will be appreciated.

Thanks in advance!

1989 4Runner SR5 4X4 3VZE

 

The high idle issue is back.
When starting cold, the idle is around 1500 rpm - even until it's warmed up. After driving a while the idle will slowly wind down and stay at a slightly unsteady 900 (was normally idling at 800 before this issue).
I'm thinking this a a vacuum hose or something. I don't think the issue is from a spark plug wire not getting connection from the distributor to the plug. Perhaps it has to do with that hose.

 

It looks like that is just your drain line for your A/C...it shouldn't be connected to anything if that is it. It just drains condensation when your ac is running. If I were to guess your idle problem may be either low coolant levels or your auxiliary air valve is sticking or the coolant lines going to your aav are clogged. Those are just a few of the problems it could be. There's a thread somewhere on here that goes through all the common causes of idle problems.

 

Thanks Smeddy. It's just odd that the issue started right after a spark plug/wire change - when it was idling fine before.

 

It may just be idling higher because you are getting better spark. Try warming up your truck by driving around for a while and then adjust your idle down to 750 where it belongs. My truck starts up around 1300...sometimes higher on colder days and then works it's way down to 750 gradually.