RPM hi after throttle cleaning

thullz · #1 (**permalink**) 06-04-2007, 11:37 AM

Hi folks

I cleaned the throttle body on my 98 SOHC EX and now the RPM is a bit higher than before, more so than it should be. The truck is reving at 1600 in N and about 1000 in D.

Any ideas why this might be and will it adjust itself?

I wasnt very aggressive in the cleaning.

Tks as always!

quicklook2 · #2 (**permalink**) 06-04-2007, 12:43 PM

maybe a vacuum leak or throttle body gasket leaking.

iac is dirty or faulty.

thullz · #3 (**permalink**) 06-04-2007, 09:35 PM

this started right after the throttle cleaning...was fine before. I cleaned the IAC a few months ago.

How can I check for a vacumn leak or a throttle body gasket leak?

aagitch · #4 (**permalink**) 06-04-2007, 09:58 PM

unplug your battery so the computer can relearn it's idle. maybe it's still trying to compensate for a dirty throttle body?

thullz · #5 (**permalink**) 06-04-2007, 10:38 PM

I disconnected the negative terminal for about 10 mins but it hasnt made a difference. The idle is not surging at all (yet) but is high and steady.

quicklook2 · #6 (**permalink**) 06-04-2007, 10:41 PM

what exactly did you do to clean the t.b.?

did you remove it?

thullz · #7 (**permalink**) 06-05-2007, 07:36 PM

I removed the air intake and used a rag soaked in carb cleaner to clean the plate and the bore.

The idle was high when i started the truck and is still high after two days of driving. Beginning to annoy my dad(his truck, my idea to clean the throttle)..lol.. I must fix this soon!

jonm61 · #8 (**permalink**) 06-05-2007, 11:48 PM

Pull the intake again and make sure there's no debris or bits of rag that are causing the throttle to hang up. Disconnect the battery for 20+ minutes to wipe the computer and start over.

Also make sure your throttle cable isn't binding on something.

quicklook2 · #9 (**permalink**) 06-06-2007, 10:33 AM

you did not remove the throttle body?

thullz · #10 (**permalink**) 06-06-2007, 11:23 AM

nope..just pulled the hose.

quicklook2 · #11 (**permalink**) 06-06-2007, 11:46 AM

i will say again, it could be a leaking gasket.

take off the t.b. replace gasket and give the t.b. a good cleaning.

also the iac is not always helped by cleaning.

it is probably best to replace the iac.

K2JJB · #12 (**permalink**) 06-06-2007, 11:51 AM

how many miles on this vehicle. In my truck I took it to the dealer at ~180k and they cleaned the throttle body for me (they were being nice) only thing is that it caused it to get rid of some of crud that was actually keeping it working properly. Some of the seals around the valve now leak air (crud kept them sealed up) and the engine can not get to a condition where it is not running to lean (so it threw a check engine code). To solve it they sealed up one of the openings in the plenum in there... at some point I will need to replace the throttle body.

In any case... long story short is that cleaning that in my case made it worse than when it was dirty!

redwing76 · #13 (**permalink**) 06-06-2007, 11:55 AM

On some Ford products theres a sticker on the throttle body that reads, "attention do not clean inside of throttle body or adjust hard stop screw special coating on throttle
plate and bore".

Your truck have that warning on the throttle body?
Source Chilton repair manual "Taurus/Sable 1996-99.