High RPM After Cleaning Throttle Body
06-13-2009, 03:52 AM
#101
Banned
Join Date: 05-31-09
Location: In your girlfriends pants
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
I can also save you the trouble. If you read earlier in this thread you'll see that I have tried a total of three different throttle bodies on my car. Two of which were clean, one of which was all carbon'ed up. The dirty one made my car run normal again, the clean ones were both the same (high idle). The problem is definitely the computer not accounting for the extra air flow which occurs with a clean throttle body as apposed to a dirty one.
06-13-2009, 08:12 AM
#102
Senior Member
I personally dont think thats what it is ,even if a pcm reflash or learn does fix the problem.
Guys are soaking the throttle body with cleaner and polishing them.
I think Like one of the other guys said the throttle body cleaner is getting in the tps sensors and changing there resistive values(permanetly) and buggering them up and thats why the relearn/reflash fixes the problem if it truly works .
Waiting to here evidence of this being the fix from the original poster of the thread because it would be nice to know for sure before I clean mine.
Heres something I found
Remove the throttle body from the vehicle. Refer to Throttle Body Assembly Replacement .
Open the throttle valve (3) of the throttle body (2).
Use a solvent soaked cloth (1) to remove dirt or carbon deposits/buildup from the throttle valve and the throttle bore.
I will add
(Not spray it directly with a pressureized aerasol can)
Ensure that the throttle valve and throttle bore are clean and dry.
Inspect that the throttle valve operates smoothly and freely.
Guys are soaking the throttle body with cleaner and polishing them.
I think Like one of the other guys said the throttle body cleaner is getting in the tps sensors and changing there resistive values(permanetly) and buggering them up and thats why the relearn/reflash fixes the problem if it truly works .
Waiting to here evidence of this being the fix from the original poster of the thread because it would be nice to know for sure before I clean mine.
Heres something I found
Remove the throttle body from the vehicle. Refer to Throttle Body Assembly Replacement .
Open the throttle valve (3) of the throttle body (2).
Use a solvent soaked cloth (1) to remove dirt or carbon deposits/buildup from the throttle valve and the throttle bore.
I will add
(Not spray it directly with a pressureized aerasol can)
Ensure that the throttle valve and throttle bore are clean and dry.
Inspect that the throttle valve operates smoothly and freely.
06-13-2009, 10:25 AM
#103
Yes, that is what I did. I used a solvent soaked rag.
I personally don't think it is a problem adjusting to the new air flow... I mean there isn't a ton more of air flow from cleaning a TB. The computer can automatically adjust for slightly smaller or larger amounts of air flow... so it has to be the result of soaking the TB and its sensors with the cleaner.
I personally don't think it is a problem adjusting to the new air flow... I mean there isn't a ton more of air flow from cleaning a TB. The computer can automatically adjust for slightly smaller or larger amounts of air flow... so it has to be the result of soaking the TB and its sensors with the cleaner.
06-13-2009, 01:09 PM
#104
Banned
Join Date: 05-31-09
Location: In your girlfriends pants
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
Yes, that is what I did. I used a solvent soaked rag.
I personally don't think it is a problem adjusting to the new air flow... I mean there isn't a ton more of air flow from cleaning a TB. The computer can automatically adjust for slightly smaller or larger amounts of air flow... so it has to be the result of soaking the TB and its sensors with the cleaner.
I personally don't think it is a problem adjusting to the new air flow... I mean there isn't a ton more of air flow from cleaning a TB. The computer can automatically adjust for slightly smaller or larger amounts of air flow... so it has to be the result of soaking the TB and its sensors with the cleaner.
06-13-2009, 05:37 PM
#105
Senior Member
Putting on a new throttle body would be the same as it would have different resistive readings as the original.
If not what is the issue ?
Maybe waiting to long to clean it.
Something changed to cause the problem and maybe the relearn/flash cures it but we all need to come up with what the root cause of the problem is.
Is it
1) spraying to much cleaner in the throttle body and it leaks into the Tps.
2)Throotle plate is getting bent and not closing all the way
3)Cleaning out the oil residue from the pvc hose making a clean bore and causing the pcm to not read the input properly(scip contamination etc).
Just thought of something else ,alot of the sensor inputs are ignored until the car warms up 12 deg and runs in closed loop.does it idle high right from the get go or after it warms up a bit ?
If not what is the issue ?
Maybe waiting to long to clean it.
Something changed to cause the problem and maybe the relearn/flash cures it but we all need to come up with what the root cause of the problem is.
Is it
1) spraying to much cleaner in the throttle body and it leaks into the Tps.
2)Throotle plate is getting bent and not closing all the way
3)Cleaning out the oil residue from the pvc hose making a clean bore and causing the pcm to not read the input properly(scip contamination etc).
Just thought of something else ,alot of the sensor inputs are ignored until the car warms up 12 deg and runs in closed loop.does it idle high right from the get go or after it warms up a bit ?
06-13-2009, 05:42 PM
#106
Member
Join Date: 08-10-08
Location: Montreal, Canada
Posts: 352
Likes: 0
Received 0 Likes
on
0 Posts
Putting on a new throttle body would be the same as it would have different resistive readings as the original.
If not what is the issue ?
Maybe waiting to long to clean it.
Something changed to cause the problem and maybe the relearn/flash cures it but we all need to come up with what the root cause of the problem is.
Is it
1) spraying to much cleaner in the throttle body and it leaks into the Tps.
2)Throotle plate is getting bent and not closing all the way
3)Cleaning out the oil residue from the pvc hose making a clean bore and causing the pcm to not read the input properly(scip contamination etc).
Just thought of something else ,alot of the sensor inputs are ignored until the car warms up 12 deg and runs in closed loop.does it idle high right from the get go or after it warms up a bit ?
If not what is the issue ?
Maybe waiting to long to clean it.
Something changed to cause the problem and maybe the relearn/flash cures it but we all need to come up with what the root cause of the problem is.
Is it
1) spraying to much cleaner in the throttle body and it leaks into the Tps.
2)Throotle plate is getting bent and not closing all the way
3)Cleaning out the oil residue from the pvc hose making a clean bore and causing the pcm to not read the input properly(scip contamination etc).
Just thought of something else ,alot of the sensor inputs are ignored until the car warms up 12 deg and runs in closed loop.does it idle high right from the get go or after it warms up a bit ?
it never does it when my car is cold
what do you think it could be?
06-13-2009, 06:56 PM
#107
Banned
Join Date: 05-31-09
Location: In your girlfriends pants
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
EVERYONE.
This is the reason the PCM needs resetting:
To allow the car to run normally the car has to adjust the throttle as the carbon builds up. So its compensating for the carbon deposits. When you clean the throttly body, you remove these. The PCM dosent realize that the carbon is gone, but is still compensating for it. Thus the throttle will be opened a small amount more than needed, thus the high idle.
Nothing more, nothing less.
This is the reason the PCM needs resetting:
To allow the car to run normally the car has to adjust the throttle as the carbon builds up. So its compensating for the carbon deposits. When you clean the throttly body, you remove these. The PCM dosent realize that the carbon is gone, but is still compensating for it. Thus the throttle will be opened a small amount more than needed, thus the high idle.
Nothing more, nothing less.
06-13-2009, 07:19 PM
#108
Senior Member
thats all fine and dandy but our TAC system does a learn everytime you start the car. so you shouldn't have to do a reflash (it doesn't work anyways.) the only other things i can think of are map/baro
06-14-2009, 11:12 AM
#110
Senior Member
I would like to clean my own but until I see a solution I think I will wait theres really not a issue yet so Im not going to bother.
If the Idle is only increasing and fluctuating when the car warms up I would think it is some sort of sensor input problem due to the car running in closed loop and ignorng the erratic input from what sensor is still to be figured out .
Im personally going with either the tps or the throttle plate motor getting contaminated with solvent soaked crud from the cleaning..
I was wondering if anyone turned the key on while veiwing the throttle plate to see it close to reset the position and then open up again and making sure it is seating all the way shut.
Last edited by Coblasts; 06-14-2009 at 11:12 AM. Reason: Automerged Doublepost
06-14-2009, 09:58 PM
#112
New Member
Join Date: 05-16-06
Location: Canada
Posts: 183
Likes: 0
Received 0 Likes
on
0 Posts
I took it to GM, and the guy did a reflash, and that brought the rpm down to 1500, as it was idling at 2500 prior. After that he told me he would try manualy entering factory values into the ECM, and that seemed to do the trick. This guy was really nice though. He only charged to for one hr only, and he worked on it for over 4.
Anyways I hope that helps someone.
Thread
Thread Starter
Forum
Replies
Last Post