What to do about 2500rpm @ Idle?

[brw1994]

Just recently and on a trip previously I did a lot of bog hole crossing and not to my suprise the engine bay was filthy. Not long after crossing through the holes the alternator fails to charge the battery above 12.1v and the battery indicator light comes on. I also get a constant 2000-2500 rpm in idle / driving and depressing the clutch. It's frustrating as it's happened twice now.

The first time I flushed the alternator and that fixed the charging problem but this time I think it will be a whole alternator out job and full clean. However this wont rectify the 2500 rpm. I have checked the distributor and it was packed full of mud and grit so I cleaned it out but this didn't fix the high rpm.

I have washed as much of everything down as I can but have no Idea what to look at next.

I have a 1990 T4R 22R petrol 5spd.

NOTE: I haven't done the alternator yet if this has anything to do with the issue.

 

[Stick Figure]

Most of my 22R experience was on carbed models in Celicas, but to stay at 2500 I would guess you have a good sized vacuum leak, a stuck idle control motor or AC idle up valve. I don't know the exact strategy Toyota used on your truck for idle control but that area seems to have both of those that could cause the issue. Try posting in the second gen forum (or maybe a moderator will move this there) and hopefully someone that knows your engine better will chime in.

 

[brw1994]

Thanks stick, but it only seems to happen crossing muddy water, so that rules out the vaccuum leak otherwise I'd have that all the time. Mine is a carbed model, not fuel injected. I forgot to mention on the rare occasion it will go back down to my steady 700rpm

 

[brw1994]

Anyone else got any ideas?

 

[HCurphy]

You would probably have more luck posting in the second gen section, this is 96-2002 section.

Good Luck.

 

[brw1994]

Yeh i realised thanks mate.