223/P0107 Intake Manifold Pressure Fault

[shane@mbtech]

I had similar issues once, it was the intake manifold temp sensor
The one on the front of the airbox, located behind the oil filter housing

Have you checked comp or leak down test at all

[0-60Motorsports]

Originally Posted by shane@mbtech

I had similar issues once, it was the intake manifold temp sensor
The one on the front of the airbox, located behind the oil filter housing

Have you checked comp or leak down test at all

In my case the car is making the power. If there were any issues with the engine it wouldn't perform like it does now.

The issue is of a leak or wiring in my case i guess. its frickin 104f at night here so im just going to wait till the AC system is done being installed at the shop and then start a proper check up.

Good luck to OP, try swapping sensors with a forum member close to you first.

[cslsuperfan]

Originally Posted by shane@mbtech

I had similar issues once, it was the intake manifold temp sensor
The one on the front of the airbox, located behind the oil filter housing

Have you checked comp or leak down test at all

Shane, the bogging down etc- are these symptoms of HG failure or bore damage?

[Mike R]

How does the ECU control the idle speed on a CSL? Normally on a Cossie, when the idle fluctuates, its because the Idle Speed Control Valve needs cleaning. This allows air to bypass the throttle butterfly (but is a single one not individual cylinder ones like on the CSL). When it gets clogged with gunk, it can't react quick enough, so the idle hunts up and down until the engine gets warm, where it then turns off (as it comes on as part of the cold start where it acts like a choke). It also turns back on to raise the idle when the air-con is switched on and can do the same thing if not clean (where it keeps over compensating one way and then the other due to the stiction caused by the gunk). If the CSL has a similar mechanical device (even if it is some sort of electronic butterfly control), if the butterflies are clogged up, it could be this?

Having seen how dirty they can get (especially after hearing about your climate), it is something I would be looking in to?

[0-60Motorsports]

Originally Posted by Mike R

How does the ECU control the idle speed on a CSL? Normally on a Cossie, when the idle fluctuates, its because the Idle Speed Control Valve needs cleaning. This allows air to bypass the throttle butterfly (but is a single one not individual cylinder ones like on the CSL). When it gets clogged with gunk, it can't react quick enough, so the idle hunts up and down until the engine gets warm, where it then turns off (as it comes on as part of the cold start where it acts like a choke). It also turns back on to raise the idle when the air-con is switched on and can do the same thing if not clean (where it keeps over compensating one way and then the other due to the stiction caused by the gunk). If the CSL has a similar mechanical device (even if it is some sort of electronic butterfly control), if the butterflies are clogged up, it could be this?

Having seen how dirty they can get (especially after hearing about your climate), it is something I would be looking in to?

Mike,

Thanks for your input and i understand what you are talking about. I have already cleaned out ICV and TB's. The weather is dusty and sandy here but i never drive the M3 in that kind of weather TBH. So when i did clean out all these parts they weren't that bad to begin with. Also the car has low KMs as you can see.

When i remove the intake manifold to change the TPS under it i'll remove the ICV again and clean it out once more. Once i do the leak tests etc i'll update the thread.

[J2LTB]

Originally Posted by Mike R

How does the ECU control the idle speed on a CSL? Normally on a Cossie, when the idle fluctuates, its because the Idle Speed Control Valve needs cleaning. This allows air to bypass the throttle butterfly (but is a single one not individual cylinder ones like on the CSL). When it gets clogged with gunk, it can't react quick enough, so the idle hunts up and down until the engine gets warm, where it then turns off (as it comes on as part of the cold start where it acts like a choke). It also turns back on to raise the idle when the air-con is switched on and can do the same thing if not clean (where it keeps over compensating one way and then the other due to the stiction caused by the gunk). If the CSL has a similar mechanical device (even if it is some sort of electronic butterfly control), if the butterflies are clogged up, it could be this?

Having seen how dirty they can get (especially after hearing about your climate), it is something I would be looking in to?

Mike the idle control valve feeds of the filtered side of the airbox. This is controls the air going to the top chrome rail which lets air to the other side of the throttle bodies. It looks similar to the injector fuel rail. I've swapped my idle control valve and it's made no difference 😔

[Mike R]

Well looks like testing Shane's theory, as that sensor is relatively cheap so I have been lead to believe .

[J2LTB]

Quick update of my problems and the fix.

One of the throttle body stop screw head's had snapped. Over time the thread had screwed itself in more holding the butterfly open when it should have been shut on idle. Thus causing a air leak😀😀😀😅
Only found when we put pressurised smoke through the idle valve rail.

The fix was to remove the damaged thread and renew the bolt and nut. Set it all up and no air leak. Car is now back to its amazing self 😆

[0-60Motorsports]

Originally Posted by J2LTB

Quick update of my problems and the fix.

One of the throttle body stop screw head's had snapped. Over time the thread had screwed itself in more holding the butterfly open when it should have been shut on idle. Thus causing a air leak😀😀😀😅
Only found when we put pressurised smoke through the idle valve rail.

The fix was to remove the damaged thread and renew the bolt and nut. Set it all up and no air leak. Car is now back to its amazing self 😆

That's awesome! Can you post a pic of the screw and its location please? Thanks.

[0-60Motorsports]

Ok, So my cars going batshit crazy.... Here are the fault codes from the CEL after replacing MAP and IAT sensors and re-soldering all wires with no breaks in between....