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Rough running - no vacuum leaks

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ThePocketGT
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Rough running - no vacuum leaks

Post by ThePocketGT » Thu Nov 10, 2022 9:16 pm

My e86 3.0si 2007 has started running rough and burning through petrol. The Ecu has thrown the following codes;
02D5A monitoring motor torque,
02c7f lambda downstream,
02c2c lambda upstream of cat,
02c2b lambda upstream of cat,
02d06 air mass system,
029f4 cat conversion.

Smoke test has been complete and no vacuum leaks found. What else could throw all these codes, has anyone experienced similar?

The lambda sensor downstream has been changed, when I clear the codes occasionally 02c2c, p2c2b, 02d06 and 029f4 appear.

The only upgrade is the Afe stage 2 intake which has been on for 11 months. Car is a daily and typical covers 250 miles a week.

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bigwinn
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Rough running - no vacuum leaks

Post by bigwinn » Thu Nov 10, 2022 9:36 pm

have you run INPA rough running to see if its a specific coil or bank giving you issues?
If the forum helped you, why not help the forum back. Thats the Z4 way! :thumbsup:

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ThePocketGT
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Rough running - no vacuum leaks

Post by ThePocketGT » Thu Nov 10, 2022 9:48 pm

bigwinn wrote: Thu Nov 10, 2022 9:36 pm have you run INPA rough running to see if its a specific coil or bank giving you issues?
I haven't got access to INPA.... only a carly😔

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Rough running - no vacuum leaks

Post by bigwinn » Thu Nov 10, 2022 9:52 pm

where you based bud? someone will have INPA near you
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Rough running - no vacuum leaks

Post by ThePocketGT » Thu Nov 10, 2022 10:04 pm

bigwinn wrote: Thu Nov 10, 2022 9:52 pm where you based bud? someone will have INPA near you
I had a quick look online and see they aren't that expensive to purchase. I guess it needs to be run on windows xp rather than windows 10

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Rough running - no vacuum leaks

Post by bigwinn » Thu Nov 10, 2022 10:06 pm

yeah find an old laptop thats still got XP on it
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smorris_12
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Rough running - no vacuum leaks

Post by smorris_12 » Thu Nov 10, 2022 11:22 pm

FWIW, INPA works fine on Win10
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Rough running - no vacuum leaks

Post by colb » Fri Nov 11, 2022 11:25 am

Increased fuel consumption is probably down to high fuel trims as going by the fault coodes you have one or more of the componants is not working or not working correctly, we are talking pre cat sensors and the Maf as probable culprits. Since you have already ruled out any air leaks the next move would be a good diagnostic scanner capable of viewing fuel trims, and exhaust sensors and Maf in live data may well pinpoint whats the root cause of your issues.
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Rough running - no vacuum leaks

Post by Special Kay » Fri Nov 11, 2022 1:01 pm

colb wrote: Fri Nov 11, 2022 11:25 am Increased fuel consumption is probably down to high fuel trims as going by the fault coodes you have one or more of the componants is not working or not working correctly, we are talking pre cat sensors and the Maf as probable culprits. Since you have already ruled out any air leaks the next move would be a good diagnostic scanner capable of viewing fuel trims, and exhaust sensors and Maf in live data may well pinpoint whats the root cause of your issues.
Colb you sound really knowledgeable :thumbsup:

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Rough running - no vacuum leaks

Post by ThePocketGT » Fri Nov 11, 2022 3:28 pm

colb wrote: Fri Nov 11, 2022 11:25 am Increased fuel consumption is probably down to high fuel trims as going by the fault coodes you have one or more of the componants is not working or not working correctly, we are talking pre cat sensors and the Maf as probable culprits. Since you have already ruled out any air leaks the next move would be a good diagnostic scanner capable of viewing fuel trims, and exhaust sensors and Maf in live data may well pinpoint whats the root cause of your issues.
thank you. I'm hoping its one of those components rather than failed manifold cats. Manifold cats are no longer available....

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Rough running - no vacuum leaks

Post by BumpyZ4 » Wed Nov 16, 2022 3:54 pm

Disconnect the MAF and see if the engine runs smoother. With the MAF unplugged the DME will revert to a default program. If the MAF is bad it should run better (although not great) with it disconnected.
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