high rev rpm idle
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,772
Likes: 1
From: Tampa FL
high rev rpm idle
need some help here, attempting to diagnois a problem i have ... personally i think it's the throw out but i'd like your alls input.
sometimes when i come off a turn and have to come to a complete stop ... like runout 1st gear and then have to put the clutch in and stop the car pretty quick due to a red light
.. the engine will still rev at like ~1000 / 900 rpm for a few seconds before coming back down to 650/700
is this due to the energy in the springs? or maybe my throwout? or wha ... honestly i dont really know and am just making guesses at this point.
thanks.
Kyle
sometimes when i come off a turn and have to come to a complete stop ... like runout 1st gear and then have to put the clutch in and stop the car pretty quick due to a red light
.. the engine will still rev at like ~1000 / 900 rpm for a few seconds before coming back down to 650/700
is this due to the energy in the springs? or maybe my throwout? or wha ... honestly i dont really know and am just making guesses at this point.
thanks.
Kyle
Le Mans Master
Joined: Feb 2004
Posts: 5,482
Likes: 1
From: Living the Taxation Dream Indiana
Sounds more like a idle control issue/non isse to me. I have an A4 so I do not see this, but in a previous car I had to clean my Idel Air Control valve and it got rid of it. Check to be sure your TB is clean of dirt or build up, but it does not sound too serious 
Last edited by JeremyMSG; Jul 11, 2005 at 10:48 AM.
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,772
Likes: 1
From: Tampa FL
Originally Posted by JeremyMSG
Sounds more like a idle control issue/non isse to me. I have an A4 so I do see this but in a previous car I had to clean my Idel Air Control valve and it got rid of it. Check to be sure your TB is clean of dirt or build up, but it does not sound too serious
verses pressing the break on an automatic where there is still gas being applied .. but i'll check the TB tomrrow.
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,772
Likes: 1
From: Tampa FL
[i posted this in General but am adding to this topic too .. just trying to get an anwser]
looking to diagnois a problem with my car ...
the revs whenever I put the clutch in wont drop down right away and will continue to stay around 1500 for a few seconds and then drop down .. orginally i thought it might be my throw out bearing and the clutch not releasing but somebody else thought it might be a fouled up TB so here are some pics .. any thoughts?
the only reason i even ask if because i know there is a connection to the valve cover through to the TB which means some oil must pass so i guess .. is this normal? or would it be beneficial to clean it out.
thanks.
looking to diagnois a problem with my car ...
the revs whenever I put the clutch in wont drop down right away and will continue to stay around 1500 for a few seconds and then drop down .. orginally i thought it might be my throw out bearing and the clutch not releasing but somebody else thought it might be a fouled up TB so here are some pics .. any thoughts?
the only reason i even ask if because i know there is a connection to the valve cover through to the TB which means some oil must pass so i guess .. is this normal? or would it be beneficial to clean it out.
thanks.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Check your intake tract for a vacuum leak. Do you have any codes?? The only way to make the engine rev is to add air or fuel.
Rev the engine to five grand and quickly close the throttle. see if it goes right to idle.
If you have access to HP Tuners, it can pin point the problem.
Bill C
Rev the engine to five grand and quickly close the throttle. see if it goes right to idle.
If you have access to HP Tuners, it can pin point the problem.
Bill C
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,772
Likes: 1
From: Tampa FL
Originally Posted by Bill Curlee
Check your intake tract for a vacuum leak. Do you have any codes?? The only way to make the engine rev is to add air or fuel.
Rev the engine to five grand and quickly close the throttle. see if it goes right to idle.
If you have access to HP Tuners, it can pin point the problem.
Bill C
Rev the engine to five grand and quickly close the throttle. see if it goes right to idle.
If you have access to HP Tuners, it can pin point the problem.
Bill C
and the only code i pulled, of any importance, was B0521H which is a tach malfunction .. but even if it was just the tach that was malfunctioning it wouldn't explain why the engine still was messed up unless for something reason the tach was part of the computer's calculation
.. but it's in the history now anyways so ..
i dunno .. i'll wait for it to reappear and go from there ..
btw .. thanks for giving me a reason to rev her up to 5 g's in the garage ..
... i'm sure my neighbors were thrilled. 
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I think you may have solved your own problem!! If the tach signal is incorrect, the PCM is going to do some strange things!!! I will look up that code in the service manual and see if I can point you in the correct direction.
BC
BC
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Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,772
Likes: 1
From: Tampa FL
Originally Posted by Bill Curlee
I just looked at your Avitar and you have a 2003!! 
Take that baby to the dealer and let them fix it!!
BC
Take that baby to the dealer and let them fix it!! BC
it's got 51k on it and is on the ext. warranty which costs me $50 for them to fix anything.
Originally Posted by Bill Curlee
I think you may have solved your own problem!! If the tach signal is incorrect, the PCM is going to do some strange things!!! I will look up that code in the service manual and see if I can point you in the correct direction.
BC
BC
Circuit Description
The instrument panel cluster (IPC) recieves engine RPM information from the powertain control module (PCM). Engine RPM input information is obtained from the PCM on a dedicated engine speed input to the IPC. The IPC also receives engine RPM data on the serial data line. The PCM is responsible for processsing and sending engine RPM data to the IPC. The IPC will only display the engine RPM data that way sent by the PCM The IPC monitors the eninge RPM output information sent from the PCM for an out of range condition.
Conditions for Setting the DTC:
- The IPC detects that the engine RPM is at least 7,400 RPM
- The above condition must be present for 1 second.
Actions taken when DTC sets:
- The IPC stores a DTC B0521
- The IPC displays engine RPM at 7,400 RPM
Conditions for Cleaing the DTC:
- The IPC detects that the engine RPM is less than 7,400 RPM
- A history DTC clears after 50 ignition cycles (minus condition)
- Code is cleared
The following conditions may cause an intermittent malfunction to occur:
- The PCM is unable to process the correct RPM data.
- Intermittent or erratic RPM signal sent from the PCM
* for intermittents and poor connections refer to Testing for Intermittent and Poor Connections on page 8-21 in Wiring Systems
....
soooo .. i know where i'll be heading next.
thanks for the help.
Last edited by Neablas; Jul 11, 2005 at 10:50 PM.