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Loss of power and warning lights

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brillomaster
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Loss of power and warning lights

Post by brillomaster » Mon Feb 26, 2018 2:23 pm

excellent, theres already a thread on this!

Was doing a trackday at Donington yesterday, and after the first three flying laps, dash lit up, and had no power. had to essentially coast down the main straight whilst restarting the car, but not happy, pulled off to the inside of redgate and sat there. Erratic idle as mentioned. Limped it back to the pits and got the code read - pending P16a7 code for MAF.

After checking everything and deciding all looked ok (including the MAF itself) decided to just unplug it and see how went. seemed to work - car started fine and then completed the rest of the day and the drive home with the MAF unplugged.

One small problem though - with the MAF unplugged, I could no longer heel and toe?!? normal driving fine, clutch in and blipping the throttle fine, but the second you dab the brake and blip the throttle - no blip. do you need to have a MAF plugged in to be able to heel and toe? Seems a strange connection to make to me. But will try replacing the MAF soon, really want to be able to heel and toe in three weeks time at Silverstone!

brillomaster
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Loss of power and warning lights

Post by brillomaster » Mon Feb 26, 2018 3:26 pm

hmmm then again... given a decent MAF is £300, gonna try cleaning it with some £4 spray first!

if that doesn't work, then it will remain unplugged, cos while I like heel and toe, its not worth £300!

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Behr
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Loss of power and warning lights

Post by Behr » Mon Feb 26, 2018 11:01 pm

I can’t speak to the whole heel and toe thing, but I can’t imagine running with the MAF disconnected long term is going to do the longevity of the engine and it’s ancillary sensors any good. I assume it will also adversely effect economy and emissions, and performance too...

I have found an OEM VDO MAF on eBay for £160. I cross referenced it from the BMW part number to the Siemens part number. The seller is Mister Auto, who I have used before and they came through for me ok. If my wanted thread doesn’t bear any fruit in the next few days then I will order a new one from them.
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Behr
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Loss of power and warning lights

Post by Behr » Sat Mar 10, 2018 11:16 pm

Just to update this thread to its conclusion: the replacement MAF came through from Mister-Auto ok. It was a genuine VDO unit in the VDO box and label but with the VDO part number milled off the MAF leaving only the Siemens number. Usual OEM parts malarkey and weirdness.

I fitted it this afternoon. Quite literally a 5 minute job. A quick run up and cleared the old code then out for a good warmup and a little blast. It’s safe to say that normal service has been resumed. What a cracking engine this is. I love BMW 6’s.

I thought the driveability gains from doing the VANOS rebuild last year along with the DISA upgrade really made little difference and have to say I was a little disappointed with the results, but now it seems that everything has been brought together. The little hesitation flat spot that I had has gone and the power really comes on right the way through - without the warning lights. Chuffed :D

Hopefully this will be useful reference to others in the future with the same code and issues.
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Loss of power and warning lights

Post by andystone » Mon Feb 17, 2020 7:51 pm

2387ECC7-61DD-455B-AE3C-CBF53B8AFB21.jpeg
2387ECC7-61DD-455B-AE3C-CBF53B8AFB21.jpeg (328.23 KiB) Viewed 733 times
Seems I’ve had the same problem. Giving the car some beans in order to overtake and exactly the same problem as the OP. What was the fix in simple English? Clean the mag?
2005 e85 z4, 2.5

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TomR
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Loss of power and warning lights

Post by TomR » Sun Apr 04, 2021 8:45 am

I know this one is a bit of an older thread, but it solved my problems!
I was getting exactly the same issue, under hard acceleration, at 4000 rpm in third it would show up the warning lights, loose all power and the engine revs were erratic at idle.
Scanned and got the codes 005E19, 0028A2.
Unplugged the MAF after reading this thread and tried again and it was all ok.
I replaced the MAF with a genuine VDO one at it has been spot on ever since.
I think it’s been on its way out for a while, I was getting some hesitation on acceleration occasionally and that has all gone now as well.
Thanks again to the forum for another little gem of information that saved an expensive trip to the garage! :thumbsup:

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colb
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Loss of power and warning lights

Post by colb » Sun Apr 04, 2021 9:14 am

I would smoke test the engine just to make sure you havn't missed finding an air leak, its not always the rubber componants that split or get holes in them, the plastic ccv pipes need checking as well as the dipstick O ring. If you have a plastic cam cover give that a good check, dealt with a mates 2.2 and eventually with smoke found that his cam cover had cracks and was crumbling around No4 plug well. Smoke test revealed that, visual check wouldn't.
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