Did I break my throttle body (Low idle)

[Tonyrodz]

Not to hijack your thread, but I'm having a crazy similar problem with a high idle, but it's in my express van. Has the 4.8 ls motor. Getting P0507. High idle. Changed the iac, then the tps--used but known good--nothing. Then changed the complete tb and threw the good sensors back on--nothing. Revs up to around 2100-2300 and won't go down. Unplugged the tps while running--nothing. Crazy.

 

[Tonyv__]

ya I don't know, I think when I was shopping for one there was like 30 different ones that all looked the same or similar, compatibility was questionable so I just went to the junk yard and yanked one off that looked decent, cleaned it up, popped it in, took maybe a couple minutes of revving and shutting off and restarting a couple times and it smoothed right out, my old one was definitely bad at that point

What did you clean with? The TB cleaner or should I look for another type of cleaner for the iac ?

 

[Doubeleive]

What did you clean with? The TB cleaner or should I look for another type of cleaner for the iac ?

ya it's just carbon any type of throttle body/carb cleaner will work, I also cleaned out the area where goes in as much as I could with a rag

 

[Doubeleive]

Not to hijack your thread, but I'm having a crazy similar problem with a high idle, but it's in my express van. Has the 4.8 ls motor. Getting P0507. High idle. Changed the iac, then the tps--used but known good--nothing. Then changed the complete tb and threw the good sensors back on--nothing. Revs up to around 2100-2300 and won't go down. Unplugged the tps while running--nothing. Crazy.

what year is it? since it has a IAC I'm assuming it's not drive by wire? maybe the throttle "butterfly" or whatever you want to call it inside is getting stuck?, you might be able to start it with the maf unplugged and intake off and see if you can see if you can give it a nudge closed, otherwise maybe it just needs a idle relearn?

 

[Tonyv__]

Not to hijack your thread, but I'm having a crazy similar problem with a high idle, but it's in my express van. Has the 4.8 ls motor. Getting P0507. High idle. Changed the iac, then the tps--used but known good--nothing. Then changed the complete tb and threw the good sensors back on--nothing. Revs up to around 2100-2300 and won't go down. Unplugged the tps while running--nothing. Crazy.

Correct me if I’m wrong anyone... but I know from past experiences on some Honda’s I used to play around with. High idle is caused from a vacuum leak...

 

[Tonyrodz]

what year is it? since it has a IAC I'm assuming it's not drive by wire? maybe the throttle "butterfly" or whatever you want to call it inside is getting stuck?, you might be able to start it with the maf unplugged and intake off and see if you can see if you can give it a nudge closed, otherwise maybe it just needs a idle relearn?

It's an 05. Maybe I'll try that, it is drive by cable.

Correct me if I’m wrong anyone... but I know from past experiences on some Honda’s I used to play around with. High idle is caused from a vacuum leak...

Mechanic said that immediately, but couldn't find a vacuum leak anywhere. He even did a smoke test. When it's running a latge sucking noise is coming from the air box (air intake) area. I'm gonna try the relearn today but I highly doubt it'll work.

 

[Tonyv__]

could be clogged up cats.

ever do a tune up?

So after 3 hours of highway driving. I used an ir temp scanner on my exhaust. In order from header/cat/tailpipe. Driver side was 289/380/260. Passenger side was 305/396/250ish. How does that sound? Possibly partially clogged?

 

[SnowDrifter]

IMO temps aren't a reliable way to tell if cats are clogged. And as it is, a few degrees variance is normal.

You'd know if your cats were clogged - you'd have no power once you step on it. If you really want to get a good idea, unscrew your upstream oxygen sensor and hook up a pressure gauge. Should be less than 5psi

 

[Scottydoggs]

cat is further away on one side too. after 3 hrs things are gonna get that hot for sure.

 

[SnowDrifter]

Lets start back at the basics. It's a little confusing for me to read through threads with everyone tossing out ideas and other guys chiming in about issues they're having. Can get a bit cluttered

You cleaned your throttle body. What was going on that necessitated cleaning?

Did you do a relearn once you cleaned it?

Lay it out in bullet points, what have you tried to remedy the issue?