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Low rpm after plenum spacer install

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Old May 24, 2014 | 09:19 AM
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Exclamation Low rpm after plenum spacer install

Question: yesterday I installed my MD copper iso thermal spacers.
Usually before the install my rpm would sit right under 1000rpm
But now it's right around 100-200 rpm, and as I'm trying to start the car it feels like it's about to give out and turn off but then it's starts up.
What do I do?????
(Sry if this is in the wrong section)
 
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Old May 24, 2014 | 09:22 AM
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Sounds like maybe you need to do a throttle body relearn process. It's in the instructions.
 
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Old May 24, 2014 | 09:29 AM
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Originally Posted by Shawno72
Sounds like maybe you need to do a throttle body relearn process. It's in the instructions.
Are you talking about this one?


1. Perform “Accelerator Pedal Released Position Learning”.
2. Perform “Throttle Valve Closed Position Learning”.
3. Start engine and warm it up to normal operating temperature.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Conform that accelerator pedal is fully released, turn ignition switch “ON” and wait 3 seconds.
6. Repeat the following (steps 7a, 7b) procedures quickly five times within 5 seconds.
7a. Fully depress the accelerator pedal (HARD)
7b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the Check Engine Light (CEL) stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the CEL is ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure the idle speed and ignition timing are within the specifications.
 
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Old May 24, 2014 | 09:40 AM
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From: Cali
Originally Posted by JarJar9104
Are you talking about this one?


1. Perform “Accelerator Pedal Released Position Learning”.
2. Perform “Throttle Valve Closed Position Learning”.
3. Start engine and warm it up to normal operating temperature.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Conform that accelerator pedal is fully released, turn ignition switch “ON” and wait 3 seconds.
6. Repeat the following (steps 7a, 7b) procedures quickly five times within 5 seconds.
7a. Fully depress the accelerator pedal (HARD)
7b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the Check Engine Light (CEL) stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the CEL is ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure the idle speed and ignition timing are within the specifications.
No this one

Resetting The Throttle Body (this step is conditional)
A Rough Idle or a SES can sometimes be caused by a change in the throttle body position sensor calibration. To correct any changes in throttle body calibration, use these procedures to recalibrate.
Accelerator Pedal Release Position Learning Procedure.
1. Make sure that the accelerator pedal is fully released. 2. Turn ignition switch “ON” and wait at least 2 seconds. 3. Turn ignition switch “OFF” wait at least 10 seconds. 4. Turn ignition switch “ON” and wait at least 2 seconds. 5. Turn ignition switch “OFF” wait at least 10 seconds.
Throttle Valve Closed Position Learning
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch is “ON”.
3. Turn ignition switch is “OFF” wait at least 10 seconds.
Make sure that the throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume Learning (Throttle Position Learning)
It's best to time with a watch/clock.
1. Perform “Accelerator Pedal Released Position Learning”.
2. Perform “Throttle Valve Closed Position Learning”.
3. Start engine and warm it up to normal operating temperature.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Conform that accelerator pedal is fully released, turn ignition switch “ON” and wait 3 seconds.
6. Repeat the following (steps 7a, 7b) procedures quickly five times within 5 seconds.
7a. Fully depress the accelerator pedal (HARD)
7b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the Check Engine Light (CEL) stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the CEL is ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure the idle speed and ignition timing are within the specifications.
 
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Old May 24, 2014 | 09:41 AM
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From: Cali
It's also on the last page here for easier reading

http://www.motordyneengineering.com/manual.pdf
 
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Old May 24, 2014 | 01:19 PM
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Is the service engine soon light suppose to stay on when the key is turned in the ON position. Can't remember if it ever went away.
 
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Old May 24, 2014 | 01:21 PM
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From: Cali
Originally Posted by JarJar9104
Is the service engine soon light suppose to stay on when the key is turned in the ON position. Can't remember if it ever went away.
It should go off once you start it. Try the relearn procedure and you should be good to go. Also you need to drive like 100 miles after the procedure before all is good. Not all at once but over a few days is fine.
 
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Old May 24, 2014 | 01:33 PM
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Originally Posted by Shawno72
It should go off once you start it. Try the relearn procedure and you should be good to go. Also you need to drive like 100 miles after the procedure before all is good. Not all at once but over a few days is fine.
Ok. I attached a quick snap shot of the rpm
I've been doing the relearn procedure I just don't know if I have been successful because the rpms are still the same. I called MD and spoke to Tony and he said that the calibration for the throttle is probably messed up so to keep trying the reset and it should go back to around 600-700.
 
Attached Thumbnails Low rpm after plenum spacer install-image.jpg  
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Old May 24, 2014 | 01:35 PM
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There was another thread and he had to drive 100 miles before everything went back to normal. Just not sure if he had a high idle. Next question, are you sure there are no vacuum leaks?
 
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Old May 24, 2014 | 01:38 PM
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Originally Posted by Shawno72
There was another thread and he had to drive 100 miles before everything went back to normal. Just not sure if he had a high idle. Next question, are you sure there are no vacuum leaks?
No, my idle never went back to normal. Its still at the first little line (200-250rpm), but idgaf, its not hurting anything. Mine doesn't dip down into struggle mode like OPs tho.

Also mine was doing that before the spacer. Mine started after I cleaned the tb. Did you touch the tb butterfly, op?
 
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Old May 24, 2014 | 02:04 PM
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Originally Posted by Shawno72
There was another thread and he had to drive 100 miles before everything went back to normal. Just not sure if he had a high idle. Next question, are you sure there are no vacuum leaks?
I'm pretty sure there isn't any type of vacuum leaks. I just checked while the car was running
 
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Old May 24, 2014 | 02:08 PM
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Originally Posted by Gdirtyfive55
No, my idle never went back to normal. Its still at the first little line (200-250rpm), but idgaf, its not hurting anything. Mine doesn't dip down into struggle mode like OPs tho.

Also mine was doing that before the spacer. Mine started after I cleaned the tb. Did you touch the tb butterfly, op?
Yeah my kinda does that dip like it's struggling to turn on. I went to town yesterday to go to the movies and as I was leaving the car didn't have an issue starting.

I was very careful with the tb. Unless the guy I had helping me did. He was handling the throttle body more when installing the copper piece.
 
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Old May 24, 2014 | 05:40 PM
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I would check the little rubber ring around the oil filler cap. Mine got stuck in the plenum a bit and caused a rough idle. Just yank it out with pliers if you can.
 
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Old May 24, 2014 | 05:52 PM
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Originally Posted by bchalks
I would check the little rubber ring around the oil filler cap. Mine got stuck in the plenum a bit and caused a rough idle. Just yank it out with pliers if you can.
Did that before I finished the install but good look tho
 
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Old May 24, 2014 | 06:02 PM
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Pretty much the same thing happened w/ mine when a 5/16 spacer was installed by a shop. Soon after I got a Mrev 2 and decided to put it on myself. I was a tech for about 7 years so I thought it would be fun to do the install and it was. This install can be done by anyone, even a beginner. Anyways the install from a shop I think one of the gaskets had a minor leak in it cuz it was bent back a little that I found when I took off the upper peice. When I did the install myself, I made sure to torque down everything to spec and made sure the gasket were correctly aligned and this fixed the problem. You should take off and redo your spacer and get a "Torque wrench" follow the guide lines Motordyne has for you to do and torque down all the bolts to the correct setting w/ the torque wrench (which should be about 100 in lbs of torque on most of em). You might have a minor leak from a gasket or from not tightening down to the right spec so u could have leakage from anywhere on your install. Redo the process and take your time it should fix it.
 

Last edited by GSpeedRevUp; May 24, 2014 at 06:12 PM.
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