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throttle body problem

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Old 01-24-2011, 09:55 AM
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dchi_t
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Default throttle body problem

I have a little problem with my throttle body, i seem to have to do the idle relearn process everytime i start the car. i was getting a P507 code (high idle), i performed the idle relearn process successfully and the idle returns to normal, however once i turn off the ignition and start the car back up, the idle goes up again and i have to do the idle relearn again! is there something screwed with the memory on the TB? the battery is good
Old 01-24-2011, 10:07 PM
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amr_electron
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At what RPM the car idles when it reaches the normal operating temperature? The reason i ask is because when you cold start the car, It will idle high ( like 1500 RPM ) & it will drop to 650 : 750 once it's fully warmed.
Old 01-25-2011, 07:19 AM
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dchi_t
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it idles @ 900-1100 when at the normal operating temperature. the TB is not keeping the reset.

I've done all the recommended reset procedures
1. ECU reset
2. throttle opening learning
3. throttle closing learning
4. idle relearn

the idle would go down to the acceptable range of 650-700 after i do the idle relearn, however, once i shut the engine off, and start it back up again, it goes back up to the 1k range. this is conerning because now i don't know if its the TB or the ECU that's gone bad.
Old 01-25-2011, 05:04 PM
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devnull420
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I thought I had a bad TB, bought a new one online, then had this same problem. I put my old one back in and did the re-learn procedure and everything was fine (and the problem that I originally had was gone too). I'd guess bad TB, mine apparently came defective when I bought it online (bought a remanufactured Hitachi one).
Old 01-25-2011, 11:26 PM
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Encino_Man
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I've got the same exact problem as you. Does your RPM jump ~500 up before falling when you shift? Everything I've read has pointed towards ECU which I honestly I don't have the money to fix just yet. It doesn't seem to like it is hurting the car (maybe using a bit more gas at idle). I'm hoping to take it in to the dealer by March but I want to try to clean my throttle body first. Because of my shift lag I feel like the butterfly isn't moving easily enough.

Apparently its like $800 if its the ECU, $600 for the part, $200 for labor and programming keys. I've seen you can buy the ECU from other sources for like $200 tho, so I guess $400 if you went that route but no warranty on the part.

Last edited by Encino_Man; 01-25-2011 at 11:27 PM.
Old 01-26-2011, 08:20 AM
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dchi_t
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I have noticed my RPMs doing that, i don't think its an ECU problem though. please keep us updated here. i've read tons of threads where other recommend the ecu reset and idle reset procedure but no one reports back if the procedure(s) actually fixed their problem or not.
Old 01-26-2011, 08:50 AM
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I had similar problem when I cleaned my TB and though I would have to go to stealer ship to have it programmed.

One night, I disconnected the battery for over night and next morning, I turn on the car and let it idle for 15~20 mins.
After that everything is fine.

I searched numerous forums, spoke to many dealers and I was getting real mad to get this problem solved...but answer was simple.
Unplug the battery, turn on the car, let it idle for 20 mins.
I didn't do any relearn process or anything.
hope it helps.
Old 01-26-2011, 09:10 AM
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dchi_t
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I've done that before, still didn't work. I'm guessing the throttle position sensor thinks the correct valve position is at where ~1k is, however, the ecu knows ~1k is out of spec and throws the P0507 code.
Old 01-26-2011, 09:11 AM
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devnull420
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Did your check engine light come on? Mine was throwing a code for idle higher than expected (or something like that)
Old 01-26-2011, 09:12 AM
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dchi_t
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yes, it has been on for 2 months, i've been trying to fix it for two months; i'm stubburn and don't want to get bent over on the counter at the dealership.
Old 01-31-2011, 11:25 AM
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dchi_t
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so this week i removed the upper plenum and thinking i may have a leak somewhere around the plenum so i applied a bead of silicon gasket all around the plenum; put everything back, did the peddle method of ECU reset along with all the other relearn procedures and i got the same results. the idle would return back to normal after the idle relearn then the idle will jump back up to 900-1000 rpm if i shut down the engine and start it up again. this is getting frustrating.
Old 01-31-2011, 01:03 PM
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Zazz93
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Sounds ECU related to me. Have you had any re-flashing or a piggyback control unit?

Possible cause


Electric throttle control actuator
Intake air leak
PCV system


Diagnostic Procedure


1. CHECK PCV HOSE CONNECTION



Confirm that PCV hose is connected correctly.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.


2. CHECK INTAKE AIR LEAK



1. Start engine and let it idle.
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 3.
NG >> Discover air leak location and repair.


3. REPLACE ECM


Last edited by Zazz93; 01-31-2011 at 01:07 PM.
Old 01-31-2011, 01:06 PM
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dchi_t
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nope, the ecu has never been touched before.
Old 01-31-2011, 03:19 PM
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dchi_t
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I'm looking at the service manual but i'm having a hard time figuring out exactly which is the PCV hose. is it the one connecting the upper plenum?
Old 01-31-2011, 05:11 PM
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Zazz93
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There are effectivly two...
Attached Thumbnails throttle body problem-pcv.jpg  
Old 01-31-2011, 05:23 PM
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dchi_t
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okay so i found the one that is not on the intake tube, i removed it and the engine dropped rpm and started to sputter. is this normal? tomorrow i will see what happens when i remove the intake tube one.
Old 02-01-2011, 01:39 AM
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Encino_Man
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Originally Posted by Zazz93
Sounds ECU related to me. Have you had any re-flashing or a piggyback control unit?
Mine had some sorta box wired into the maf wire apparently. The guy who owned it before me said he took it off and thats when the check engine light came on. He gave me the chip and it was some ebay $45 dollar increase horsepower job. Thats why I feel like mine is ECU related.
Old 02-01-2011, 02:34 AM
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scoobyrex247
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i'm having the same problem after i cleaned the TB with TB cleaner. I do the complete idle relearn and everything goes to normal, then at the next engine start it idle at 1000rpm and ses light. fml. this is the 4 time I disconnect the battery and do the re-learn.
Old 02-01-2011, 07:00 AM
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dchi_t
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Originally Posted by scoobyrex247
i'm having the same problem after i cleaned the TB with TB cleaner. I do the complete idle relearn and everything goes to normal, then at the next engine start it idle at 1000rpm and ses light. fml. this is the 4 time I disconnect the battery and do the re-learn.
that is exactly what is happening to me!
Old 02-01-2011, 07:58 AM
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Zazz93
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You guys should also try cleaning the MAF with MAF cleaner. But, the problem I see is it seems to be able to read eveything correctly but doesn't hold the settings in memory. Kinda like a motherboard with a dead battery. Do you guys have to constantly set the time on your radios?


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