Need help...problem with N52 misfire

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brewsterE30M3
Posts: 333
Joined: Fri Jan 27, 2006 11:02 pm
Location: Hunterdon County

Need help...problem with N52 misfire

Post by brewsterE30M3 »

Got Fault Codes 29d1 and 29d2 on my '06 e90 330i N52 with 205k miles which means #5 and #6 are misfiring. The spark plugs have 109k on them.
Also getting a strong gasoline smell from the exhaust.
And also the 2 year old battery is getting seriously drained...now dead!
I started simple by changing both #5 and #6 spark plugs.....no change.
Ok so I then changed both #5 and #6 coils with new OE "updated" coils......no change.
Hmmm..are the fuel injectors the problem, dumping raw fuel in those two cylinders???
I then picked up 2 new FI from the dealer and installed.....still no change, still misfiring!

Geez what else is left?

To be continued tomorrow.....COMPRESSION TEST? COMPUTER ?

ANY RECOMMENDATIONS OR SUGGESTIONS ARE GREATLY APPRECIATED

THANKS,
Bruce D.

brewsterE30M3
Posts: 333
Joined: Fri Jan 27, 2006 11:02 pm
Location: Hunterdon County

Re: Need help...problem with N52 misfire. UPDATE

Post by brewsterE30M3 »

No. 6 cylinder has compression ( or lack thereof) 10 psi
Suspect some valves are open, hopefully due to carbon buildup and not mechanical issue.
TBC....

RAYADAM
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Re: Need help...problem with N52 misfire

Post by RAYADAM »

Perform leak down test , you'll know what the issue is.
Ray
2011 X5d
2018 Shelby GT350

brewsterE30M3
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Joined: Fri Jan 27, 2006 11:02 pm
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Re: Need help...problem with N52 misfire

Post by brewsterE30M3 »

Thanks Ray.....probably should have done a compression test FIRST...my bad.
Let this be a lesson....compression test and leak down next.
My son has decided to sell his baby.

Bruce D.

RealM3E30
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Re: Need help...problem with N52 misfire

Post by RealM3E30 »

My guess was "Coil Packs", I keep an extra on the bench 8)
91 E30 M//3 GQ
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07 E91 328XIT
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sgoatley2001e46
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Re: Need help...problem with N52 misfire

Post by sgoatley2001e46 »

Forgive me if this doesn't come through. I'm sending from my phone. I was doing a little research on this issue, and you guys might not be alone... The attached screenshot is from e90post.com. The issue seems common for cyl 6.
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BJerolimic
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Joined: Wed Sep 15, 2004 2:24 pm
Location: Glen Ridge, NJ . . . . . . '98 318ti - '01 M5 - '08 X5

Re: Need help...problem with N52 misfire

Post by BJerolimic »

strange timing for this thread as my wife's X5 is having similar issues, also with N52 but only with Cylinder 6 and it only has 35k on it. We do get a bit of gas smell too so where-as before I was leaning towards plug/coil now I'm wondering if I have a stuck exhaust valve as well

I don't have tools for a compression test (nor knowledge on how to perform one), do I suck it up and take it to a mechanic or should I try plugs/coils first? anything special needed for changing fuel injectors?
Image

and gone but not forgotten:
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sgoatley2001e46
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Re: Need help...problem with N52 misfire

Post by sgoatley2001e46 »

That is interesting timing, Brent. Curiosity got me so just started Googling after Bruce's original post. Although I'd only posted the one screenshot from the e90 forum, there were tons of other comments/threads about it being an issue for cylinder 6. Obviously, forum posts should be taken with a grain of salt, but the thread I was following seemed to include some folks with moderate degrees of apparent intelligence (i.e., not the "check out my slammed car, bro" type).

Your mileage seems low, but the age is right. Not sure if time plays an issue as would mileage. In your case, maybe check the injectors too?

Now, as far as I know there quite a few similarities between the N52 and N51. With all the N51 cars here in the northeast (like mine), is this something we should worry about too?

BJerolimic
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Joined: Wed Sep 15, 2004 2:24 pm
Location: Glen Ridge, NJ . . . . . . '98 318ti - '01 M5 - '08 X5

Re: Need help...problem with N52 misfire

Post by BJerolimic »

So today I pulled the plug and coil, plug looked normal

I put the plug into cylinder 1, and the coil into cylinder 2

I have done 46 miles since but so far it hasn't misfired yet so I still haven't narrowed it down
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and gone but not forgotten:
'00 323Ci Steel Grey / Black Dinan & UUC & Schnitzer mods
'89 325iX Diamond Black / Black 4dr 5spd Dinan chip, Ireland exhaust, H&R+Koni
'01 525iTa

RAYADAM
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Re: Need help...problem with N52 misfire

Post by RAYADAM »

Is it possible the same change over valve broke on yours (like it did on Bruce's)? it's a possibility and really wouldn't know unless you heard any abnormal noises before it failed (if indeed did).
it's possible the broken piece could of "passed" , or you have a failing coil which is quite common on N52's. It's very rare injectors go bad from what I see here.might be worth taking a look at the adjuster unit mentioned above.
Ray
2011 X5d
2018 Shelby GT350

BJerolimic
Posts: 747
Joined: Wed Sep 15, 2004 2:24 pm
Location: Glen Ridge, NJ . . . . . . '98 318ti - '01 M5 - '08 X5

Re: Need help...problem with N52 misfire

Post by BJerolimic »

after about 80 miles I got a pending misfire code on Cylinder 2, which is where I had put the coil from the previously misfiring Cylinder 6. So it looks like the cause for mine is a simple coil issue and hopefully this easy fix will be all she needs, I will install it this weekend and I will post back here if it ever comes back


thanks all!
Image

and gone but not forgotten:
'00 323Ci Steel Grey / Black Dinan & UUC & Schnitzer mods
'89 325iX Diamond Black / Black 4dr 5spd Dinan chip, Ireland exhaust, H&R+Koni
'01 525iTa

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