91 ls400 IAC valve(idle control valve) working?
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91 ls400 IAC valve(idle control valve) working?
Hello Im trying to fix the low idle problem(car idling at 400 in gear warm engine) and (idling at 420 in park warm engine). I tried to adjust the tps but it basically only raises it around 20 rpms from the low side of the sensor to the high. I unplug the Idle Control Valve(front center of motor) and the engine does no rpm change whatsoever. My question is.. Which is bad the tps or the Idle control valve. Is the tps telling the idle control to raise idle but the idle control is dead or?? Lost on this one! ThanksNel
#2
The idle control valve regulates the air in , that's how it controls the idle , it does this by moving in and out , unplugging it won't change the idle as it will stay in the posistion it was in when you unplugged it !!
You need to take it off clean it out and replace the bearing in it , that way you can be sure any problems are not coming from that unit , if you like I can E-Mail you a diagram .
You need to take it off clean it out and replace the bearing in it , that way you can be sure any problems are not coming from that unit , if you like I can E-Mail you a diagram .
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Thanks for the help!! My email is porshapower@webtv.net. I took the whole thing apart and all I saw was the spring and the other side had a round large item attatched to a bolt that turned freely and threaded in and out to adjust the air? Kind of reminded me of a mini starter. Thanks Nelson
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Also is it normal for the tps to only adjust the idle around 20 rpms total from one end of adjustment turned all the way to the other end of adjustment? Seems like a had another car that when I turned the tps it would adjust it from like 400rpms to 1200rpms?? Thanks again
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Thanks for the help!! My email is porshapower@webtv.net. I took the whole thing apart and all I saw was the spring and the other side had a round large item attatched to a bolt that turned freely and threaded in and out to adjust the air? Kind of reminded me of a mini starter. Thanks Nelson
did you remove the bearings? and how?
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Thanks for the diagram! Wasnt the bearing threaded onto to a piece that threaded in and out of the main piece. I know that if I spun it then it would close it up more and if I loosened it then it would open it up more. I left it to closed I think because when I first started it after taking it apart it didnt idle high rpm on the cold engine like it normally does. The next morning it was fine. Started it up and it idled at 850rpms and then warmed up and dropped to 400 like it used to do before I opened it. That bearing can be bought? ThanksNel
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Wow...guess you have been playing with lexus cars for a long time. By looking at it you cant tell if its bad correct? I just ask for a bearing and take that number? I also got a check engine code tonight coming home tonight. Do you know how to pull codes? Im kind of happy to have the check engine code as weird as this sounds because now maybe it will point at something. Thanks again!! Nel
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Hello, Found out how to retrieve codes. Got a code 71 "egr system malfunction". Looked under hood where I was messing with hoses the day before and the harness for the thing next to the egr was not plugged in all the way. Plugged it in until it clicked and that problem solved. Now on for the low idle... I am going to try to find this bearing and do the repair. Thanks again!! Nel
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I had same problem with low idle and where did you found that .. email me omar5691@gmail.com or reply me back
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I had same problem with low idle and where did you found that .. email me omar5691@gmail.com or reply me back
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