Code 1215

[DUDEK]

Did anyone figure this issue out? There is numerous threads on this problem with no clear solutions. There has to be someone out there that had this issue and solved it!

1995 318Ti

The problem: After warm starts the engine starts and then dies...you can keep starting it and it will do the same thing over and over, unless you rev the car for about 20-30 seconds & then the idle stabilizes. The only code that shows up is 1215 (air flow meter)...replaced the AFM with a used unit & the intake boot and all vac hoses and it's still doing the same thing. The strange thing is that in the winter months it never does this only the other seasons Would this indicate that it's still a problem with the AFM or related wiring? Is there anything else that could be causing this code? Any help would be greatly appreciated.

[Wayne 962]

I know that you checked everything, but this is a sign of a big vacuum leak *somewhere*. I would go one step further and get a vacuum gauge and see if you can plug it into the intake and then measure vacuum as the throttle opens. If the vacuum is weak at idle, or doesn't change much, then something is definitely leaking. This causes this error, and the *exact* problems that you are experiencing.

The fact that it only happens in warm weather makes sense too. Rubber hoses expand in the summer, and contract in the cold weather. Contraction will seal it in the winter months...

-Wayne

[DUDEK]

Thanks for the response Wayne! I will do a vacuum leak test this week and let you know what the outcome is. The fact that it only happens in warm weather makes sense too. Rubber hoses expand in the summer, and contract in the cold weather. Contraction will seal it in the winter months... I agree...But if this is the case, why does the engine idle normally after reving it for about 20-30 seconds? It should keep on stalling or get worse from the heat

-Lukasz

[Wayne 962]

Originally posted by DUDEK
Thanks for the response Wayne! I will do a vacuum leak test this week and let you know what the outcome is. The fact that it only happens in warm weather makes sense too. Rubber hoses expand in the summer, and contract in the cold weather. Contraction will seal it in the winter months... I agree...But if this is the case, why does the engine idle normally after reving it for about 20-30 seconds? It should keep on stalling or get worse from the heat

-Lukasz

I don't know. You didn't mention that it ran fine after about 30 seconds or so. Is this the case?

-Wayne

[DUDEK]

'about 20-30 seconds & then the idle stabilizes.'

Yes...it runs fine after about 30 seconds...only if you rev the motor above 3000rpms for that time...otherwise it keeps on stalling if you do not rev the motor. This only happens on warm starts.

[Wayne 962]

Sounds like it's not getting enough fuel for the start, like a problem with the cold start circuit...

-Wayne

[mfowler]

Is it possibly that if it is a vane type AFM that the vane itself has corrosion in the path, thus requiring the vane to move past it to clean some corrosion?

[DUDEK]

Originally posted by Wayne at Pelican Parts
Sounds like it's not getting enough fuel for the start, like a problem with the cold start circuit...
-Wayne

Checked for vacuum leaks...there is none. I also checked the spark plugs which are a year old and all four are whitish in color (lean/not enough fuel). It looks like the engine is running lean (...it does seem sluggish under 3000 rpms). I do not think that not enough fuel just at the cold start would cause the plugs to be this color? Would this still indicate a problem with the cold start?

-Lukasz

[Wayne 962]

Again, a vacuum leak or faulty air flow sensor will give this condition as well. Check to see if the flaps in the sensor can move freely?

How did you check for a vacuum leak?

-Wayne

[Wayne 962]

One way to test is to disconnect the boot between the manifold and the throttle body, and see if there is any change. The car shouldn't really run at all with a huge leak there...

-Wayne

[DUDEK]

Originally posted by Wayne at Pelican Parts
One way to test is to disconnect the boot between the manifold and the throttle body, and see if there is any change. The car shouldn't really run at all with a huge leak there...

-Wayne

Yes...I disconnected the boot between the throttle body and Air Flow Meter and the car did not run. I am leaning toward the used replacement AFM being faulty. Is there a way to test the AFM unit?

A little off topic but the answer might help to resolve this issue: I have a friend with a 1995 318is and his car was showing code 1226 (knock sensor)...we replaced the knock sensor and checked for codes again and this code was no longer present. Does this mean that if the problem is fixed the code erases it self or at least does not come up with the pedal method

-Lukasz

[DUDEK]

If this issue was not difficult enough to resolve...it gets better. I checked the codes the other day (pedal method) and now there is a new code 1226 (#2 knock sensor) and the 1215 code (mass air flow) is gone The car currently does not have the warm start problem...because it's not summer weather, but on the last tank of gas...the gas mileage was poor.

[Wayne 962]

Originally posted by DUDEK
Yes...I disconnected the boot between the throttle body and Air Flow Meter and the car did not run. I am leaning toward the used replacement AFM being faulty. Is there a way to test the AFM unit?

A little off topic but the answer might help to resolve this issue: I have a friend with a 1995 318is and his car was showing code 1226 (knock sensor)...we replaced the knock sensor and checked for codes again and this code was no longer present. Does this mean that if the problem is fixed the code erases it self or at least does not come up with the pedal method

-Lukasz

The knock sensor failure code is triggered when the computer gets a false signal or no reference signal from the sensor. So, replacing it *should* immediately fix any codes that were being pushed...

-Wayne

[Wayne 962]

Originally posted by DUDEK
If this issue was not difficult enough to resolve...it gets better. I checked the codes the other day (pedal method) and now there is a new code 1226 (#2 knock sensor) and the 1215 code (mass air flow) is gone The car currently does not have the warm start problem...because it's not summer weather, but on the last tank of gas...the gas mileage was poor.

Hmm, you could try replacing the knock sensor, but the sensor is more for adusting the timing when it's too advanced and pings the engine. It shouldnt have too much effect on the engine when starting. Although a bad sensor could theoretically cause problems I suppose if it was giving off a ping signal when the car actually wasn't pinging.

Try replacing the sensor? (not easy to get to)

http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search.cgi?command=show_part_page&please_wait=N&make=POR&model=BE36&section=ELignt&page=3&bookmark=15&part_number=12-14-1-734-580-M14

-Wayne

[DUDEK]

Update...
I checked the codes again (pedal method) and all my codes have disappeared (code 1444) I have heard that the car (ECM) takes a bit of time to adapt to a new Air Flow Meter and thats why all the codes it might have been causing went away? So by the looks of it the problem was a faulty AFM and the used unit I installed turned out to be good. Unfortunately I can not check if the warm start problem went away because it only acts up during summer. Thanks for all the help Wayne!

-Lukasz