[CloudFX]

Hey guys, so I decided to join the forum after trying and exhausting every solution there is with my N43.

Here's my issue, the car hesitates to start properly if the engine is warmed up, I've seen it do it on cold starts as well but like once in 100 or more cranks, most of the time it's doing it when the engine is warm. This has been going on for three years now, my bet is on leaky injectors since they are all index 3 known to have issues but I'm also scared of changing all 4 injectors on a perfectly working car just to find out that wasn't the problem. So now, moving on to the next thing, so far I've changed the following.

New OE starter
Complete timing chain and tensioner kit OE
New plugs
New coils
New crankshaft sensor OE ( used to throw the code )

Ran several diagnostics on ISTA-D trying to get to the bottom of it every single day since I have the tester at home. The car throws no fault codes apart from 2EF8 DME Thermostat activation ( already bought the thermostat waiting for it to be replaced )

There's no HPFP low pressure code or something wrong related to it ( however, once I've checked the pressure value in ISTA as soon as I stop the engine the pressure drops somewhat rapidly from 150k mbar and after about 10minutes it will reach a value of 5k mbar)
No LPFP issue as well ( holds pressure )
No missfire codes, never had 'em
No surging or hesitation, pulls perfectly
Cyl compression is over 11
Injector values on ista are between the values of -30 and +30

The dealer has a hard time telling why it does it and can't seem to know why, went to some other good mechanics that I know and their bet seems to either be the fuel pressure regulator or the injectors but most likely they said the injectors might leak. It also smells like gasoline when the car is cold but I suppose that's because the catalyst only does it's job when it's up to temp.

Does anyone have some sort of ideas? The car runs perfectly, never let me down in three years apart from this dreaded and never ending hard starting issue. I've noticed that the spark plugs on cyl 2 and 3 were really black when I changed them the last time.

The car has exactly 100k miles and it's an 08. Checked all injectors, they're all index 3


*copied from the topic since no one is looking in the n43 topic

[N5GKP]

Originally Posted by CloudFX

Hey guys, so I decided to join the forum after trying and exhausting every solution there is with my N43.

Here's my issue, the car hesitates to start properly if the engine is warmed up, I've seen it do it on cold starts as well but like once in 100 or more cranks, most of the time it's doing it when the engine is warm. This has been going on for three years now, my bet is on leaky injectors since they are all index 3 known to have issues but I'm also scared of changing all 4 injectors on a perfectly working car just to find out that wasn't the problem. So now, moving on to the next thing, so far I've changed the following.

New OE starter
Complete timing chain and tensioner kit OE
New plugs
New coils
New crankshaft sensor OE ( used to throw the code )

Ran several diagnostics on ISTA-D trying to get to the bottom of it every single day since I have the tester at home. The car throws no fault codes apart from 2EF8 DME Thermostat activation ( already bought the thermostat waiting for it to be replaced )

There's no HPFP low pressure code or something wrong related to it ( however, once I've checked the pressure value in ISTA as soon as I stop the engine the pressure drops somewhat rapidly from 150k mbar and after about 10minutes it will reach a value of 5k mbar)
No LPFP issue as well ( holds pressure )
No missfire codes, never had 'em
No surging or hesitation, pulls perfectly
Cyl compression is over 11
Injector values on ista are between the values of -30 and +30

The dealer has a hard time telling why it does it and can't seem to know why, went to some other good mechanics that I know and their bet seems to either be the fuel pressure regulator or the injectors but most likely they said the injectors might leak. It also smells like gasoline when the car is cold but I suppose that's because the catalyst only does it's job when it's up to temp.

Does anyone have some sort of ideas? The car runs perfectly, never let me down in three years apart from this dreaded and never ending hard starting issue. I've noticed that the spark plugs on cyl 2 and 3 were really black when I changed them the last time.

The car has exactly 100k miles and it's an 08. Checked all injectors, they're all index 3


*copied from the topic since no one is looking in the n43 topic

I've had an issue before at work which took me a little while to get to the bottom of (mainly because of looking into the injection side of things and not exploring other avenues).
Leave the car to go stone cold, read out coolant temp sensor value (should obviously read cold). Drive it, get it red hot & then recheck what coolant temp sensor value reads out at (again should obviously read hot). If it doesn't that could potentially be the issue

[Dormermike]

Good call on temp sensor.

I am not sure what "hesitates to start" means - does the starter turn immediately ? Does it fire and cut out ? Does it just spin over for a long time ?

[CloudFX]

The starter is brand new and turns constantly, from what I can tell it's as if it can't ignite all cylinders properly in order to start.


I'll check the temp values today

[CloudFX]

There you go, the injector values seemed kinda high, the tend to balance then jump up again. Third photo is with the engine being turned off. Oh and I also filmed it, as soon as I stop the engine the high pressure rail starts to lose pressure rapidly

[N5GKP]

Have you checked the 'injector quantity compensation' values?
Obviously you need the 6 (2 lines of 3) digit number off of each injector. Via ista it should be service function a service function available in power train, can't remember the exact location. If the values aren't stored it can cause issues!
Worth noting that the last digit can differ by one or two numbers when actually stored in the DME.

[CloudFX]

Just checked, they're stored

[CloudFX]

So... no ideas?