COLD START RPM (1 Viewer)

cruiserdan

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Normal........ :eek:


Well OK, maybe not "normal" but it is the nature of the 1FZ.

There is a way to tone it down. I requires removal of the IAC from the throttle body and "tricking" it with Orings.

I can expand on that if you wish............ :beer:
 
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I tried the high idle cold start fix with the "0" rings. One ring did nothing! Two rings helped at the initial start-up (1,000 -1,200 rmp's). However, after warm up the idle dropped to 200 rpm's and stalled. I restarted and drove around for about 20 minutes. Everytime I came to a stop the same thing happened. Any ideas as to why I can't maintain the proper rpm's with the rings installed. :dunno:

Thanks,

Steve 94' (105,000)
 

cruiserdan

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How many times have you cycled the ignition since you did that? The ECM looses it's mind about the IAC setting when the power is interupted. It takes several ignition on-off cycles for it to re-set. If you have done that and still have the low idle you may have a bind in the worm drive or you may have to go back to one oring.

BTW the oring trick was on 80's COOL tech list some time back......

Regards..........Dan :beer:
 

Wrench

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It is normal. I would not mess with it. All toyota engines do this and they last til 300k plus. I think Toyota knows ho to design an engine.
 

semlin

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small good filter 90915-20004Re: COLD START RPM

Tenn if you can hear the valves think about getting the small good oil filter 90915-20004 that Toyota introduced partly to address start up rattle.

As for start up, mine does it too, anywhere from 16-2000 rpm then down to 1600 rpm depending on its mood. To avoid tranny clunk I always wait till it drops to 1100 rpm by itself so I think that I burn at least a gallon of gas a week warming this car up. I have heard it is a glitch but it is very veyr widespread and I have never seen a solution from anyone other than the o-ring.
 
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WARNING:

EXTREME THREAD REVIVAL
--------------------------

You've got to be kidding. This high rpm startup is normal??? My engine sounds like I should be landing on an aircraft carrier when I turn it on in the morning....

My idle dropped to a "normal" 6-800rpm for 1 day after I replaced my o2 sensors, but not the high idle is back. Oh, and the low 300rpm idle in Drive at a stop light is really annoying since replacing the o2 sensors. Happened occasionally before, but now is all the time.

I was going to tear into the IAC, PCV, throttle cable, throttle body, MAF and go on a clean/test/replace mission.....but maybe this is normal

wow
 
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My 3fe jumps to about 1600rpm and then slowly settles down to 1200rpm until I put it into gear. If I allow it to warm up, it will settle down to normal idling rpm.
 
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Oh wise IH8MUD forum I leave my cruisers future in your wisdom. If the consensus is that this is normal than so be it.

It jumps up to 1,800 rpm, is loud as hell and will settle down to 600rpm (which i consider normal) if I let it sit 5 minutes or so.

So my intermittent low idle has to be a different issue. I'm really hoping its not the engine wire harness.

Its still strange that it cold start up idled at 800rpm down to 600rpm very quickly after replacing o2 sensors and pulling EFI fuse. Felt d@mn nice if I say so myself. Back to 1,800 rpm now though.
 
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The high idle is NOT normal and only a problem with '93-'94 1fze motors. Some OBDII '95s may also have this problem but NO '96-'97. The o-ring method is the solution, however in some cases a metal washer works much better. No cold idle should be any where near 2000rpm.
 
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Try disconnecting your battery for a little while. Then after about 3-5 start-ups your idle (both cold and hot) should return to normal. I have been doing a lot of electrical work on my '94 lately and have found the idle seems to be all over the place once the battery has been disconnected or a sensor has been replaced.
 
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Did an off car throttle body cleaning, IAC cleaning, MAF cleaning and PCV replacement today. After buttoning it back up, connecting battery, pulling EFI fuse for a minute and firing it up for the first time of the day....here's how the rpm's looked

1,400rpm
1,200rpm (2 seconds)
800-900rpm (2 seconds)

So within 5 seconds the rpm dropped from 1,400 to 800'ish. Thats what I'm talking about :)

Another 7 minutes and I was pretty warm and idling at 600rpm. Another 3 minutes and it was fully warm and still at 600rpm.

On a side note to this thread, the low idle appeared gone as well.

Over the next week I'll keep an eye on the start up rpm and see what happens.
 
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How many times have you cycled the ignition since you did that? The ECM looses it's mind about the IAC setting when the power is interupted. It takes several ignition on-off cycles for it to re-set. :beer:
Hey Dan I am intrigued about your post... can you elaborate? So does ECM check for IAC position and how it does that?

Since my low idle now seems to permanently vanish... yayy
I had now vow to wage war on High Idle start up issue which had come back again and it is driving me crazy.
 

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