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Correct idle speed for HO 4.0 AW4?

Daedalus454

Daedalus454

NAXJA Forum User
Location
Simi Valley, CA
I've seen lots of threads discussing MT and Renix idle speeds, but I couldn't find one with the correct idle speeds for a HO engine with an automatic. Mine (OBDII '96) idles at a little over 1000 RPM in drive while stopped with brakes on, which seems pretty high.

Thanks in advance.
 
check for vacuum leaks, intake/exhaust manifold loose bolts or leaks.

maybe you have a hidden extended idle switch
 
Flushed the tranny this weekend when I installed my Explorer aux cooler, and it fixed a LOT of problems, including the in gear idle speed. Now idles around 800 RPM. I think the tranny may have had ATF in it.
 
My manual says to use Dexron III, not ATF.
 
I used Castrol Domestic Multi-Vehicle Dexron III / Mercon. I ended up putting around 10 qts through the tranny before it started coming out red and clear. I guess mildly burnt, brownish, not at all transparent fluid would have different friction properties than Dexron III. :doh:

But yeah, *major* improvement. It shifts SO nice and smooth now. And idling in gear, if just sits there instead of pulling hard against the brake.
 
outlander said:
I hope it had ATF in it:confused1
Click to expand...

X2:twak: ATF = Automatic Transmission Fluid................
 
Sorry, I thought folks would know what I was talking about...
 
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