1fzfe revving idle (1 Viewer)

[White Stripe]

My 1994 1fze has a strange issue. I had replaced the EFI fuse the other day. Since then when it's in park the idle goes from about 600 rpm to 2000 rpm. It quickly revs to 2000, then drops quickly to 600. As soon as it hits 600 it quickly revs to 2000. It does this only when in park. Any ideas?

 

[Stevesnj]

The computer is learning the engine systems again. Try disconnecting the neutral battery cable for 15 min then start again. It could take a few min of revving for it to catch up.

 

[White Stripe]

The computer is learning the engine systems again. Try disconnecting the neutral battery cable for 15 min then start again. It could take a few min of revving for it to catch up.

Ok thanks!

 

[DirtScaresMe]

The computer is learning the engine systems again. Try disconnecting the neutral battery cable for 15 min then start again. It could take a few min of revving for it to catch up.

I have the same problem when I disconnect my battery. The first few start ups, the first in particular, are a little weird. It's disconcerting because it always makes me think I screwed something up.

 

[retrofive]

Yep, couple cycles it will relearn. Mine absolutely hates me when I disconnect the battery or whatnot. Drive in town, turn off, drive in town, turn off, drive on freeway (50mph for awhile), repeat, after several of these cycles should return to normal.

 

[White Stripe]

Cool. Maybe I'll pull the IAC first and clean it up good b4 I reset it.

 

[Stevesnj]

Cool. Maybe I'll pull the IAC first and clean it up good b4 I reset it.

Be careful, that thing is expensive

 

[Tools R Us]

Idle cycling is most often the TPS related. The connector isn't weather sealed, so if it has been wet, can hold water and cause this issue. In this case, we clean and dry, then apply silicone grease, this solves the problem and prevents it in the future.

 

[White Stripe]

Well I think my IAC is shorted out. Blew the efi fuse. Installed new fuse and IAC wiring started smoking. So I got a used iac coming from classic cruisers.