[9352e90]

Symptom: Rough idle/ misfire at start up, goes away once the car restarts and engine warms up. SES light until restart, then clears.

Code P0201 (electrical circuit for cyl #1 fuel injector) , from OBD. Tried switching the coil and error code stays with cylinder one.

Does this sound like a bad injector, I didn't think this was a common issue on the n52.

[GoRomeo]

Originally Posted by 9352e90

Symptom: Rough idle/ misfire at start up, goes away once the car restarts and engine warms up. SES light until restart, then clears.

Code P0201 (electrical circuit for cyl #1 fuel injector) , from OBD. Tried switching the coil and error code stays with cylinder one.

Does this sound like a bad injector, I didn't think this was a common issue on the n52.

Most likely a leaky injector...?

[Pladi]

are you misfiring only on that cylinder 1 injector ? If answer is yes then yes check the connection to it too.

[9352e90]

Originally Posted by GoRomeo

Most likely a leaky injector...?

Could it be a bad seal?

[9352e90]

Originally Posted by Pladi

are you misfiring only on that cylinder 1 injector ? If answer is yes then yes check the connection to it too.

Just pull the connector off and just put it back on?

[Pladi]

Originally Posted by 9352e90

Just pull the connector off and just put it back on?

you did not answer my suuper simple question ...

[niche20]

Sounds like you may have a bad injector. I would start with replacing coils and plugs, then if it continues replace with index 12 injectors. This solved my rough running issue.

[MysticRob]

OP, a simple google search sure points to what everyone is saying. Any fuel injector can fail. Same with wiring.

https://www.yourmechanic.com/article...pencer-clayton

[feuer]

Originally Posted by niche20

Sounds like you may have a bad injector. I would start with replacing coils and plugs, then if it continues replace with index 12 injectors. This solved my rough running issue.

[nhhiep]

pour in a can of BG 44K. mine had starting issue and it helps a lot.

[Pladi]

Originally Posted by nhhiep

pour in a can of BG 44K. mine had starting issue and it helps a lot.

where are you pouring this ?

[9352e90]

Originally Posted by Pladi

you did not answer my suuper simple question ...

Yes, just number 1

[Wolf 335]

[MysticRob]

Originally Posted by nhhiep

pour in a can of BG 44K. mine had starting issue and it helps a lot.

Originally Posted by Pladi

where are you pouring this ?

In the windshield washer bottle. It sprays onto the windshield, smears to the point of driver blindness, causes wreck, and voila, OP no longer needs to worry about misfires. Or follow directions and put it in the gas tank if that's your thing.

Originally Posted by Wolf 335

LOL, no doubt.
OP, since you've pretty much narrowed it down to the injector, check the seal, check the injector itself, wiring, throw some cleaner thru the system, etc, and finally replace if nothing else works.

[Pladi]

Originally Posted by MysticRob

In the windshield washer bottle. It sprays onto the windshield, smears to the point of driver blindness, causes wreck, and voila, OP no longer needs to worry about misfires. Or follow directions and put it in the gas tank if that's your thing.



LOL, no doubt.
OP, since you've pretty much narrowed it down to the injector, check the seal, check the injector itself, wiring, throw some cleaner thru the system, etc, and finally replace if nothing else works.

I would never pour injector cleaners because these are solenoid injectors bosch specifically states not to.. might as well put it in ur windshield washer might do less harm ..

[MysticRob]

Originally Posted by Pladi

I would never pour injector cleaners because these are solenoid injectors bosch specifically states not to.. might as well put it in ur windshield washer might do less harm ..

Link to that info from Bosch please?
BMW sells their own 82140413341 rebadged Techron cleaner...

[nsjames]

Originally Posted by Pladi

are you misfiring only on that cylinder 1 injector ? If answer is yes then yes check the connection to it too.

this x10000

my random cyl 1 misfire that didn't follow the injector and persisted through injector replacement was a harness issue.

Just go ahead and pull the injector harness from the rail and re tension every terminal with a pick.

[gbalthrop]

Originally Posted by nsjames

...my random cyl 1 misfire that didn't follow the injector and persisted through injector replacement was a harness issue.

QUESTION: Is it SAFE (to the DME) to test for injector pulse at pin #2 of the injector with a DIGITAL multimeter, with the connector removed from the injector and either (1) measuring voltage in reference to ground, or (2) measuring Ohms in reference to ground; in each test, Red probe of meter on Pin#2 of injector connector & motor running.

Obviously one could also have break in the Orange wires providing 12V+ to each connector, and that is safely tested at Pin#1 with volt meter.

How did you diagnose Injector Harness fault?

Same question as it relates to testing for trigger signal at coil connector, Pin#1???

Thanks,
George

[Pladi]

Originally Posted by MysticRob

Link to that info from Bosch please?
BMW sells their own 82140413341 rebadged Techron cleaner...

https://www.boschautoparts.com/docum...c-e57a1640bfd3

Page 5/6. So put it in your washer fluid.

[MysticRob]

Originally Posted by Pladi

https://www.boschautoparts.com/docum...c-e57a1640bfd3

Page 5/6. So put it in your washer fluid.

Carefully reread what that says. It specifically is talking about fuel injector testers causing issues, not fuel system cleaners like Seafoam, Techron, etc. Many people run fuel system cleaners thru their cars with Bosch, or any other, injectors. And again, BMW sells it's own rebranded Techron cleaner for maintenance purposes. Do you believe they are trying to destroy all our cars?

"Many injector testers have a cleaning function, which can eliminate some deposits. But cleaning multi-point and high-pressure injectors can cause..."

[Pladi]

Originally Posted by MysticRob

Carefully reread what that says. It specifically is talking about fuel injector testers causing issues, not fuel system cleaners like Seafoam, Techron, etc. Many people run fuel system cleaners thru their cars with Bosch, or any other, injectors. And again, BMW sells it's own rebranded Techron cleaner for maintenance purposes. Do you believe they are trying to destroy all our cars?

"Many injector testers have a cleaning function, which can eliminate some deposits. But cleaning multi-point and high-pressure injectors can cause..."

I personally stay away from them ever since i bough some techron from a trip in the states. Literally right after my tank of gas with techron was done my car started misfiring on cold starts. When i took apart my spark plugs cylinder 1 was soaked in fuel. My car ran fine before that. It could have been a coincidence. But for today's cars injector cleaners are not useful. After 60k miles i would replace injectors instead. Leaky injectors can cause much bigger issues...

Not to mention good gas has additives such as shel and others already. So why put more ?

[cparke]

Originally Posted by 9352e90

Symptom: Rough idle/ misfire at start up, goes away once the car restarts and engine warms up. SES light until restart, then clears.

Code P0201 (electrical circuit for cyl #1 fuel injector) , from OBD. Tried switching the coil and error code stays with cylinder one.

Does this sound like a bad injector, I didn't think this was a common issue on the n52.

I believe the code means the fuel injector on the cylinder failed the ECU 's resistance test at start up and has been disabled for safety reasons.

I just had the same thing happen on my cylinder 3 injector. Constant misfire on the cylinder upon cold start-up after sitting outdoors overnight, goes away once the engine warms up if you clear the code while the engine is running or re-start the car (i.e. invoke the test).

I moved the bad injector from cylinder 3 to cylinder 5 and the misfire condition happened again in a few days on cylinder 5 the same way. So I finally replaced it. Based on these experiences, I think a simple resistance test on the injector should have identified the problem if it were done without letting the engine warm up the injector and make the problem go away.

However, does anyone know the correct resistance range for the N52 non-turbo fuel injectors? These are the naturally aspirated engines using standard injectors that don't get coded into the ECU.