Car idle and acceleration hesitating

[m3f_MOTRSPRT]

Unfortunately the ignition coils between an e46 and e36 have different plugs . So I've not been able to troubleshoot them.

Can I read the bad coils in any such way thru INPA or NCS Expert?


2007 M6

2003 M3

1998 M3

2011 Ducati 1198

[m3f_Eclipsetrbo420A]

I don't know how to do this?





2007 M6

2003 M3

1998 M3

2011 Ducati 1198

Well I solved the issue and documented it. I had a vacuum leak at the rear of the VC at one of the grommets. Check out the videos for the fix. My idle is rock solid and the car is pulling better It feels like, at the least its MUCH more smooth. very enjoyable now.



I document the "investigation" haha heres all the videos!

VIDEO 1 - Initial sign of smoke at the rear of motor on exhaust side ---------------------------------

M52 vacuum leak 2 - YouTube












VIDEO 2 - Closer look -----------------------------------------------------------------------------

M52 vacuum leak - smoke test 1 - YouTube












VIDEO 2 - VC plasstic cover off, found it coming from the coil area of CYL 6-------------------------

M52 vacuum leak smoke test 3 - YouTube












VIDEO 3 - Coil out found loose grommet------------------------------------------------------------

M52 Vacuum leak smoke test 3 - YouTube












VIDEO 4 - Loose bolt out, exposed leak -----------------------------------------------------------

M52 vacuum leak smoke test 5 - YouTube












VIDEO 5 - explanation of the test -----------------------------------------------------------------

M52 bank 2 fuel trim issue - found with smoke machine! - YouTube












VIDEO 6 - CLoser look at smoke machine in operation -----------------------------------------------

Smoke machine on M52 run through - YouTube

[m3f_Eclipsetrbo420A]

For a forced induction car, you should make sure to have absolutely zero leaks, that's a closed system after the compressor, only her out should be from the bypass valve not should enter back in after the HFM

[m3f_MOTRSPRT]

Dang! Videos are very informative. I can see the advantage of using one now. Without the right tools a guy simply shotguns repairs or goes on a wild goose chase. Like me buying another MAF...all the other ideas I've tried haven't really cost me a lot of money but mostly time. And they've been things I've needed to fix or replace anyway. I wonder if I can rent something like this?


2007 M6

2003 M3

1998 M3

2011 Ducati 1198

[m3f_Eclipsetrbo420A]

Well the one you see in the video there, I made using a water bottle from college a glow plug and the battery charger I'll get you the video of that when I first did it hang on

[m3f_Eclipsetrbo420A]

Here it is, homemade evaporation smoke machine is from a couple years ago when I had my black 95 m3



You Tube

[m3f_Eclipsetrbo420A]

If you take your supercharger off, do it at 2 pounds for your intake tract at the throttlebody. Then, with the supercharger on obviously you want to do maybe 1 to 2 PSI more than the amount of boost you're running, that way you'll know if you're losing metered air there or you can find the area where you're pulling in unmetered air under vacuum. Youll pressurize right at the compressor wheel, if you leave the supercharger on.

[m3f_MOTRSPRT]

Seems simple enough to make! Currently the SC is off the car for rebuilding, but the car had this problem even before removing it. This might be a fun project to build and use.


2007 M6

2003 M3

1998 M3

2011 Ducati 1198

[m3f_Eclipsetrbo420A]

Yeah it works well, if you have any questions just shoot me a PM if you have a battery charger, the rest of it should cost you $10 at most

[m3f_Olemiss540]

This brings back some horrible memories (spent chasing VAC leaks). Similar to you, I would replace anything and everything trying to chase down idle issues, and FINALLY solved it. I tried to DIY smoke machines, but I HIGHLY recommend spending the $150 bucks to have a shop smoke test if your DIY does not find anything.


I would replace ALL Vacuum hoses, check that the "Turkey neck" is well seated into the manifold. Replace the VAC hoses from the brake booster to manifold, manifold to fuel rail, ICV to manifold, intake to ICV, CCV hoses. If this does not solve it, check the MAF wiring from the MAF plug to the DME (had the inline resistor break on me before).


If it is not a vacuum leak, you will eventually throw a code for the root cause (hopefully) such as TPS, CPS, Crank sensor, etc. Are you having any coolant level issues or oil level issues that might point to a headgasket problem? Test your blow off valve to make sure it is holding pressure and not leaking.


Good luck sorting out, been down this road dozens of times since I didn't have my own smoke machine.....

[m3f_Eclipsetrbo420A]

I also forgot to mention, if you're supercharger is off the car right now what tune are you running?

[m3f_Braymond141]

I also forgot to mention, if you're supercharger is off the car right now what tune are you running?

It isn't necessary to revert the tune back. It will run N/A without the charger just fine (if some sort of intake is setup with the MAF).



You should always pressure test at your boost level, maybe even higher.

[m3f_MOTRSPRT]

That's correct. And this info came straight from Dinan. About 6 years ago I had it the sc rebuilt and the car ran just fine. If I didn't have this issue prior I would be leaning heavily towards the ecu being the issue (in all reality I can't rule that out right now either).

How can I check the cam sensor without actually getting to it? Will it throw a code?


2007 M6

2003 M3

1998 M3

2011 Ducati 1198

[m3f_Eclipsetrbo420A]

That's cool so fuel distribution is controlled by HFM flow and a 1:1 fuel pressure regulator ?

[m3f_MOTRSPRT]

That's cool so fuel distribution is controlled by HFM flow and a 1:1 fuel pressure regulator ?

I don't have the exact knowledge about those things but it makes sense.

I've been reading on the camshaft position sensor. My symptoms resemble a lot of the symptoms produced by a bad sensor. Maybe it's time to get the check engine light read. I have to use a laptop from work since my home laptop is a MacBook Pro, and not supported by INPA.


2007 M6

2003 M3

1998 M3

2011 Ducati 1198