high idle, runs fine. low idle, misfire

ToyotaFear

New Member
Apr 3, 2008
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Burlington Wa.
Code 51 is your TPS. Probably from adjusting that "idle screw" as you put it. If its the screw I'm thinking it is(throttle stop screw) than you need to adjust it. Back out the throttle stop screw until you see space between it and the throttle lever. Then bring the screw in until it touches and tighten the check nut. See the TSRM for details.

http://www.supramania.com/forums/showthread.php?t=46793&highlight=remove+throttle+body
 

AJ'S 88NA

New Member
Jul 26, 2007
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Florida
ToyotaFear;1004022 said:
Code 51 is your TPS. Probably from adjusting that "idle screw" as you put it. If its the screw I'm thinking it is(throttle stop screw) than you need to adjust it. Back out the throttle stop screw until you see space between it and the throttle lever. Then bring the screw in until it touches and tighten the check nut. See the TSRM for details.

http://www.supramania.com/forums/showthread.php?t=46793&highlight=remove+throttle+body
Already been pointed out, read the whole thread:)
 

supramacist

Banned
Apr 8, 2006
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The Grassy Knole
The code 51 is like an audible code. The diagnostics will stop flashing it when you get it tuned out. And then you reset and adjust the timing.

And if it's being covered it isn't being covered enough. Surely I'm not the only person noticing a rash of vaf and tps codes being throne up lately. The vaf's are norm but the 51 is off the charts.

I wonder if this could have anything to do with climate sensitivity brought on by a flux in seasonal change.
 

Supraman1313

Banned
Mar 23, 2008
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Quakertown, Pa
ok, so I replaced the O2 sensor and at first it did nothing. So I drove it for about a mile and then came back to it an hour later, started it up and the idle came down from 1500 to 750 in about 10 seconds but then after a few more seconds it slowly started to idle lower, down to 500rpm and running rather rough. I gave it some gas and she started idling at 800 and was fine. I tried it again and she idled down to 500rpm, after a few seconds it starts to come back up to about 800rpm. The car runs perfectly fine when i'm not idling. This weekend I plan on taking out my intake manifold and shit and clean it all.

Any suggestions??

Oh and code 51 came up because I had it in gear...haha.
 

Finnon

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Mar 26, 2006
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South Shields, Tyne & Wear ENGLAND
hmm its probably nothing to do with your fault but i had a high idle on mine >1200

i tried a few things. cleaned up the csi and the iscv i fitted new plugs plus a variety of other things. nothing changed it. then i swapped the ecu's over and it cured it
 

Supraman1313

Banned
Mar 23, 2008
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Quakertown, Pa
Ok, so I picked up a new throttle body to intake manifold gasket from a Toyota dealership (I know, more money, but it's the real deal. plus I got a discount that made it worth it). And so I took my throttle body off, used a toothbrush and cleaned the whole inside and vac holes. Turns out one of them were clogged. Clean up a couple of pipes and stuff and put it all back in. I turned back the "idle screw" and started her up and oh man, she purrs at 700rpm (I think a little low, but it works). BUT, she still misfires a bit at lower rpms.

Could my timing be off? I can't see any problems with the ignition cuz i changed the plus, wires, cap, and rotor. Any ideas??
 

AJ'S 88NA

New Member
Jul 26, 2007
2,419
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Florida
Supraman1313;1010007 said:
Ok, so I picked up a new throttle body to intake manifold gasket from a Toyota dealership (I know, more money, but it's the real deal. plus I got a discount that made it worth it). And so I took my throttle body off, used a toothbrush and cleaned the whole inside and vac holes. Turns out one of them were clogged. Clean up a couple of pipes and stuff and put it all back in. I turned back the "idle screw" and started her up and oh man, she purrs at 700rpm (I think a little low, but it works). BUT, she still misfires a bit at lower rpms.

Could my timing be off? I can't see any problems with the ignition cuz i changed the plus, wires, cap, and rotor. Any ideas??
If you haven't had a timing light on it you need to. Follow the TSRM to time it with a jumper wire. And did you set the stop screw back according to the TSRM?