when i started my car last week, the rpm would suddenly drop and the car would shut off. this happened to me 3 times and it was starting to worry me. my g has 65k miles on it. i searched online for a possible cause and came across this thread: https://www.myg37.com/forums/g37-cou...-start-up.html

according to the thread, the issue could be due to a dirty throttle body. so this weekend i got together with a friend and got to work! we did the following on the car:

1 - cleaned throttle body using 'throttle body cleaner'. just unscrewed the factory intake and removed the 4 screws from the throttle body and cleaned it up. a lot of charcoal/tar was built up on the inside. we did not pull the throttle valve open out of fear of having sensors go off.

2 - cleaned the mas airflow sensors located near the intake filters, since i had a spare can handle from cleaning it once on my m3.

3 - poured 3/4 seafoam can into the vacuum hose near brake fluid and 1/4 into the gas tank. let it sit for 10 mins that drove it like crazy to get every junk out.

4 - reset the ecu internally using youtube instructions. very easy and helpful.

it was a fun little project and the results were amazing. i did notice the car running and changing gears more smoothly.

it idles at 500 rpm. is that normal? i don't remember what it was before.

just thought i'd share this with the group to see if someone has done something similar and if there was something i missed. cheers!

 

500-600 is about right. my car did the same thing, died at startup 3 times. however, since my car only has 22,000 miles and a 2010, it was still under warranty. so, i took it to the dealer and just played dumb and said the car died 3 times at startup. they knew right away that it was the TB, and even said it was a common issue. they just replaced them under warranty. fine by me. now my car idles around 500-600 and is much smoother.

 

500rpm should be ok, as long as it does not feel like it is sputtering or a bouncing idle.
I have heard after the seafoam vacuum hose you have to change the spark plugs, not entirely sure though.


With all that work it should feel like a sprinter after the starting gun goes off.

 

yes i have also heard that spark plugs and possibly an oil change is a must after seafoam. which spark plugs do you recommend? i was planning on taking the car to the dealer for an oil change and also get the TSB done on the transmission reprogram.

 

You need to do a idle air volume relearn. A quick search will help you find the procedure.

 

this thread has excellent info on this:
https://www.myg37.com/forums/d-i-y-i...le-bodies.html

here are steps i found to do the idle air volume relearn without consult-ii:
Without CONSULT-II
NOTE:
It is better to count the time accurately with a clock.
It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit has a malfunction.
1. Perform EC-42, "Accelerator Pedal Released Position Learning" .
2. Perform EC-42, "Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quickly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the specifications.

 

Go with OEM, dont try to find a better replacement. I believe OEM are called "Denso Iridium"