M156 engine, CEL p0191, p2187, p0451
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e55 2004
M156 engine, CEL p0191, p2187, p0451
Hi, everyone!
I have problem with my car, from this forum find out that M156 engine has common problem with intake manifold gasket leak and purge valve. Does anyone know what is wrong with my car or had the same problem? Check engine light is on, P0191, P2187, P0451. Car drives good, powerful, no misfires, only little rough when idling Please help! Thank you
I have problem with my car, from this forum find out that M156 engine has common problem with intake manifold gasket leak and purge valve. Does anyone know what is wrong with my car or had the same problem? Check engine light is on, P0191, P2187, P0451. Car drives good, powerful, no misfires, only little rough when idling Please help! Thank you
Last edited by e55igor1; Mar 31, 2013 at 11:10 PM.
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From: NY
E63S | X5
P0191 - Fuel rail pressure sensor circuit range/performance
P0451 - Evap emission control system pressure sensor range/performance
P2187 - System too lean bank 1
It sounds like you have a vacuum leak. I think the MAF's can be stubborn from time to time so I would check for leaks there. I would also look around the fuel pressure regulator (there should be a vacuum line heading to it and that's the one to look for).
--The idling problem, however, is what sounds like a vacuum leak. Especially because it doesn't have a problem once you're past idle which generally points at fuel pressure regulator related leaks.
Just a thought on a place to start
P0451 - Evap emission control system pressure sensor range/performance
P2187 - System too lean bank 1
It sounds like you have a vacuum leak. I think the MAF's can be stubborn from time to time so I would check for leaks there. I would also look around the fuel pressure regulator (there should be a vacuum line heading to it and that's the one to look for).
--The idling problem, however, is what sounds like a vacuum leak. Especially because it doesn't have a problem once you're past idle which generally points at fuel pressure regulator related leaks.
Just a thought on a place to start
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e55 2004
I am guessing too that is the vacuum leak, any other thoughts? Bad sensors? Check engine comes and goes.
Did the first test: Cleared the error codes, started the engine and idling for 5 min. Checked the codes again, no faults.
Second test: driving, after 1 min check engine light, faults again
Seams like accelerating makes difference.....
Did the first test: Cleared the error codes, started the engine and idling for 5 min. Checked the codes again, no faults.
Second test: driving, after 1 min check engine light, faults again
Seams like accelerating makes difference.....
Last edited by e55igor1; Mar 31, 2013 at 11:53 PM.
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From: Canada
2014 E63S Wagon
hmm, i've having similar issues. I thought it was just my air filters.
I didn't get the P0191, but i did get:
P2422 evap system vent solenoid valve stuck closed
P0451 - Evap emission control system pressure sensor range/performance
P2187 - System too lean bank 1
and the code for bank 2 too lean.
I already cleared the codes, I'll see if it comes up again, if it does I'll take it to the dealers...
I didn't get the P0191, but i did get:
P2422 evap system vent solenoid valve stuck closed
P0451 - Evap emission control system pressure sensor range/performance
P2187 - System too lean bank 1
and the code for bank 2 too lean.
I already cleared the codes, I'll see if it comes up again, if it does I'll take it to the dealers...
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Thread Starter
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e55 2004
My car is out of warranty. I planning to spray some MAF cleaner around intake manifold to check where is leak located. Thank you so much for your time and help! Will update if I find out something.
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2009 C63
Hi, everyone!
I have problem with my car, from this forum find out that M156 engine has common problem with intake manifold gasket leak and purge valve. Does anyone know what is wrong with my car or had the same problem? Check engine light is on, P0191, P2187, P0451. Car drives good, powerful, no misfires, only little rough when idling Please help! Thank you
I have problem with my car, from this forum find out that M156 engine has common problem with intake manifold gasket leak and purge valve. Does anyone know what is wrong with my car or had the same problem? Check engine light is on, P0191, P2187, P0451. Car drives good, powerful, no misfires, only little rough when idling Please help! Thank you
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Audi A5 6MT, C63 AMG
do you have an aftermarket tune? I have kept some money on the table for a tune but want to clear my doubts regarding inherent issues
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e55 2004
Check engine again, but only P0191 code
Hi, everyone!
I have problem with my car, from this forum find out that M156 engine has common problem with intake manifold gasket leak and purge valve. Does anyone know what is wrong with my car or had the same problem? Check engine light is on, P0191, P2187, P0451. Car drives good, powerful, no misfires, only little rough when idling Please help! Thank you
I have problem with my car, from this forum find out that M156 engine has common problem with intake manifold gasket leak and purge valve. Does anyone know what is wrong with my car or had the same problem? Check engine light is on, P0191, P2187, P0451. Car drives good, powerful, no misfires, only little rough when idling Please help! Thank you
Thread Starter
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e55 2004
Update!!!
Finally, 
I found and resolved the problem with "Check Engine Light". In my case it was bad PCV Valve / Breather hose (part of emission system), part# A156 010 03 70 ($90.00). In regular maintenance routine, it needs to be changed every 70,000 miles.
Maybe this information will be helpful who have similar problem with M156 6.2 engine
Symptoms:
If the faults codes P0191 P2187 P0451 present, CEL is ON, can be white smoke from exhaust after cold start, no misfiring, engine oil around the PCV Valve, engine oil dipstick popping out, part# A156 010 03 70 must be replaced.
In some cases, it can be the Purge Valve, fault code P0444. Check if it pulsing by holding it, you will fill the vibration if it working good.
Thank you everyone for help!!!
I found and resolved the problem with "Check Engine Light". In my case it was bad PCV Valve / Breather hose (part of emission system), part# A156 010 03 70 ($90.00). In regular maintenance routine, it needs to be changed every 70,000 miles. Maybe this information will be helpful who have similar problem with M156 6.2 engine
Symptoms:
If the faults codes P0191 P2187 P0451 present, CEL is ON, can be white smoke from exhaust after cold start, no misfiring, engine oil around the PCV Valve, engine oil dipstick popping out, part# A156 010 03 70 must be replaced.
In some cases, it can be the Purge Valve, fault code P0444. Check if it pulsing by holding it, you will fill the vibration if it working good.
Thank you everyone for help!!!
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C63 & Mustang Mach1(s)
Glad you found the problem. Can I please have a little more detail on the purge valve? Location, what to pull to check the pressure, etc. I'm getting the P0171 code but it could be the dipstick like you said maybe I didn't push it down all the way. I'm going to clean my MAF sensors as I have K&Ns but I cleaned them months before the CEL tripped. CEL showed up right after I got the Euro v4 upgrade.
Can't imagine its my PVC valve car only has 26k on the clock.
Can't imagine its my PVC valve car only has 26k on the clock.
Thread Starter
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e55 2004
Glad you found the problem. Can I please have a little more detail on the purge valve? Location, what to pull to check the pressure, etc. I'm getting the P0171 code but it could be the dipstick like you said maybe I didn't push it down all the way. I'm going to clean my MAF sensors as I have K&Ns but I cleaned them months before the CEL tripped. CEL showed up right after I got the Euro v4 upgrade. Can't imagine its my PVC valve car only has 26k on the clock.
Thread Starter
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e55 2004
