I understand the throttle body and intake can collect crud, but I wonder is this much crud to excessive in an '86 with 122k miles? It's close to an 1/8" thick in places. You're looking at the air intake with the TB removed from the front of the pickup.

 

Emissions controlled vehicles will do that.

You should have seen the intake plenum on my x-wife's Honda/Isuzu!

I took it off, filled it with gasoline, let it sit overnight, and shook it around.
... then steam cleaned it.

BTW, seven years, four posts...
Welcome to the forum!

 

^ Gotcha. I will do the same, thanks.

And thanks for the welcome. I was wondering if someone would catch that. Do we get points for lurking?

 

Oh, no.
Believe me you don't need to do that.
Just pointing out how bad it can get with a stuck EGR.

Sure.
Rep points for lurking!

 

Ah, OK. The EGR is next on the list...

 

They all do it. When you cut the engine off, you will see a oil mist rise out of the engine if you have the intake hose off. After awhile this builds up and needs to be cleaned out, it messes up your air going around the throttle blades and makes the idle air control valve stick.

 

^ I see, thank you. This regular cleaning, is that something which can be handled by a half can of carb cleaner sprayed into the throttle body every 3000 miles or so? I've done that in the past on other vehicles.

 

That would help, but it's best to take the idle air control motor off and the throttle body off and clean them off the engine. You should not need to do it every 3000 miles. More like every 50,000 miles.

 

I have sprayed carb cleaner into the throttle plate for many a year. I do it every six months. Keeps it running great. Now I read more often, should be using Fuel Injector Cleaner....there's supposedly a coating on the throttle plate that carb cleaner eats away at. Who knows?

 

Use "Throttle Body" spray cleaner not Carburetor cleaner. The former won't hurt the Teflon coating on the bore/blades. Fuel injector cleaner is typically meant to run through the fuel system to clean the inside and tips of the injectors - you don't want to pour it in the throttle body.

 

Copied that, thanks. Next scheduled cleaning -- December, 2022.

...
I live rural. This means if the local parts store even had throttle body cleaner spray, it would have cost $9. I did look

I vaguely remember reading the teflon coating in TB did not start until some time after '86? If you have it there's a sticker saying so underhood somewhere? If this TB had a any type of coating, it's gone.

I don't know about spray carb cleaner vs injector fuel treatment other than I have Seafoam in the tank which didn't appear to have any effect. But when I sprayed carb cleaner, the idle jumped to over 2000RPMs from 1200-ish and stayed there. (The previous owner replaced the idle set screw with a longer screw and used it as an idle adjustment.)

 

I found the reference regarding the Teflon coating:

"Beginning in 1991, Ford began using a Sludge Tolerant Throttle Body design which includes a special slick Teflon coating inside the throttle bore ... The issue is harsh cleaning can remove the sensitive Teflon coating eliminating the protective qualities. These Throttle Bodies can be identified by a black/yellow sticker on the Throttle Body warning against cleaning or adjusting..."

From: How to Clean and Test your IAC - FSB Forums

Sorry, it's off-site, but that's where I remember reading about it.

 

Thanks for citing the source! I'd rep ya if I could.

No problem it's from FSB, there's some decent stuff there....

 

This is what I have heard(but can't back it up). The teflon coating was one of those "better ideas" from Ford that never did work, and you can go ahead and use something that eats the coating off, because it's going to get dirty anyway, just like the old ones did, and you can then clean it like the old ones, every so often.

 

I gave him a "rep" and credited you, ctubutis!