High Revs

[Payner]

Hi folks
1992 FlareSide 5L 5speed here.
Here is my problem:
When I push the clutch in to change gears she jumps to around 2500-3000 rpms and when approaching a stop when I hold the clutch in same thing but does very gradually drop to 1000rpm but this takes way too long to happen it usually drops by 200-300rpm steps. This is very annoying and can't be good for the engine. My experience with past standards is that the idle should drop immediately upon pushing the clutch in.
I have replaced the IAC (high idle motor), the TPS and put a new distributor cap on.

Oh, by the way, no check engine light is coming on.

ANY IDEAS???

[Northern Supercrew]

have you cleaned your throttle body? excess grime could be stopping it from closing enough to bring the idle down, or the butterfly in there could be worn to the point of air seepage around it.

[taisa899]

leaking intake gaskets

[SKRWZ]

leaking intake gaskets

I agree sounds like a vacuum leak

[Payner]

found the tube running from the airbox (about 1' dia.) disconnected at the air box and a loose fit to the canister under the battery, also disconnected the battery and reconnected in hopes the ECM would reset. Just waiting for it to warm up for a test drive.

will update later today

How do you check for an intake gasket leak with that big ugly plenum, (air intake), covering the top of the engine?

[taisa899]

unlit propane torch along mating area's if idle shoots up you've got a leak

[Payner]

Thanks for the suggestions..
I fixed the hose and tube and after reconnecting the battery it seems to be a lot better. Not perfect yet so I will try the other suggestions, (cleaning the Throttle Body and check for leaks) on a day I can get the 84 Monte Carlo and the Honda Goldwing out of the garage.

AGAIN Thanks so much

[taisa899]

keep us updated

[Payner]

Tried the unlit propane torch, no change in the idle
cleaned the throttle body, no change
butterflies seem to be working just fine
can't see any vacuum line cracks or hole
it just passed an emissions test with flying colors so can't see the EGR being a problem

I am wondering what other sensors or modules control throttle idle?

[LayinHp]

only thing i can think of really is the intake plenem gasket but if theres no change with the torch then i dunno :icon_question:

[taisa899]

gotta be a vaccum line somewhere

[TA_GTA]

same thing happend on my old dodges both 318 and 360 had the issue i tried everything to the 318 and NOTHING, turns out it was a crack in the intake manifold. The 360's problem was the gasket between the air cleaner and the manifold. hope this helps

[shelbyx1]

have you checked your pcv valve they can get stuck causeing an internal vacc leak.

[taisa899]

what's your TPS voltage at?

[Payner]

After all the spray I put through the throttle body I took it to town the other day and it seemed OK so I am gonna cross my fingers and leave it alone for a while to see what happens

[taisa899]

good luck hope it's ok

[James-06SCL]

Sounds simple, but have you checked the throttle cable itself? My 97 would stick / freeze at really low temperatures causing the same symptoms. Likely had moisture in the cable.

[Jensen]

^^^^ Im with him on this one, back in school had a buddy that had a 95 standard, his throttle body would freeze open depending how much gas he gave it in the morning. Kinda funny to see, but not too great on his I6 and tranny which wasnt meant to take off from a stop at 3000rpm almost every 3 min.

[truckguy94]

I just replaced the throttle cable when the truck (94 F-150) was tuned up...same symptoms....was freezing at cold temp's....not too expensive, right from Ford dealer...maybe $30- 35...alls well now

[Payner]

You ain't gonna believe this but....
after a few days of running good it started over again, I checked around for vaccum leaks again and found none so I decided to check and fill fluids. The anti-freeze was down a pint and a half and the oil down a quart, I filled these and it has been running good ever since. This makes absolutely no sense to me but what the hell eh?

[Destructicon]

TPS sticking, binding or not installed correctly? If that's the case I hear Toyota may have a solution.:icon_twisted: