My car doesn't idle when started in the morning

Tiny
MARTINKODUA
  • 2000 LEXUS GS 300
  • 124,000 MILES

So engine shakes till it heats up then it stops, secondly when I turn on the a/c the rpm goes down. Cars has undergone alot of changes with new wiring etc etf

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Tuesday, February 14th, 2012 AT 12:42 PM

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Tiny
KHLOW2008
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The poor idlign during initial startup indicates the cold start system is not working correctly.

If the MIL is indicating, get a scan done and let me know the EXACT trouble code.

If you do not have any trouble codes, get the throttle body and IAC cleaned and retest.

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Tuesday, February 14th, 2012 AT 1:27 PM
Tiny
MARTINKODUA
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Thank you very much, would check that now, secondly can you also give me a picture of how to fix the vacuum hoses just around where the actuator is. Thank you

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Tuesday, February 14th, 2012 AT 2:09 PM
Tiny
KHLOW2008
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I am not sure which actuator you are referring to so I have included all the various vacuum diagrams and schematics available in our database. Hope ithey are helpful.

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Tuesday, February 14th, 2012 AT 4:02 PM
Tiny
MARTINKODUA
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Thank you very much, I would let someone take a look and explain it to me, its the 4th picture but I dont seem to understand it well. And the codes are P0758, P0135 and P0155. The Vacuum hoses comes from a small black round bottle just above the Starter and I dont know where those two hoses connects to

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Tuesday, February 14th, 2012 AT 6:07 PM
Tiny
KHLOW2008
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If you can't get anybody to explain the thing to you, snap a few pictures of the intake manifold and I will try to explain to you.

P0758 is a fault with the #2 solenoid of the transmission.
P0135 and P0155 are faults with the Or sensors.

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Tuesday, February 14th, 2012 AT 9:10 PM
Tiny
MARTINKODUA
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Hello Please see attached picture from my engine. There are two holes coming from a small bottle I think thats the vacuum tank but I dont know where the hoses goes to including the one coming from underneath the air intake chamber

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Wednesday, February 15th, 2012 AT 11:37 AM
Tiny
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I can't see the surrounding of the vacuum but the hoses in the diagram seems to be the vacuum source from the manifold and the vacuum. If that is the case, the upper hose in diagram is the vacuum source and it goes to a vacuum switching valve which should be somewhere near the vacuum tank. Where does the vacuum tank hoses lead to?

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Wednesday, February 15th, 2012 AT 9:38 PM
Tiny
MARTINKODUA
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I studied your 4th diagram today and have able to solve the vacuum hoses. Now my next problem is when I put on the a/c my idle goes low instead of going a little bit highto power the a/c effectively and finally where is the cold start for my car? Bcos when I start in the morning the idle goes up and comes down so quickly that the engine doesn't heat up so it shakes till it heats before it becomes normal.

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Wednesday, February 15th, 2012 AT 9:59 PM
Tiny
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The IACV system is the one you just fixed.

Ensure the circuit is working correctly.

Check the throttle control motor operations. Ensure throttle body is clean as dirt accumulation inside throttle body can cause erratic idling.

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Wednesday, February 15th, 2012 AT 10:31 PM
Tiny
MARTINKODUA
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I have cleaned the Throttle Body, would check on the throttle motor and get back to you on this one. You have been very helpful, I would definitely send a donation but I dont have a credit so we would have to find another way of donating something to you. Secondly when I turn the a/c on isnt there supposed to be something like an actuator which should raise my idle? I still seem not to understand why went I switch on the a/c my idle goes down which makes the engine shake, is this also a problem with the Throttle motor please?

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Thursday, February 16th, 2012 AT 1:15 PM

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