MAF Sensor on 1998 V70 non-turbo BAD? 1275749

Post by **Eddystone** » 18 Feb 2019, 10:37

So, if you get a MAF sensor error when the car stalls out and refuses to start, unplug the MAF and happily drive away, is that a pretty definitely a bad MAF? The one that's on there has markings on it indicating it was pulled from a junk yard years ago.

Car usually runs just fine, but has periodically stalled (maybe six times over two months) and has now twice refused to restart.

These two cars are getting ahead of me...

Post by **misha** » 18 Feb 2019, 11:43

Could be a Maf connector too....they are prone to failure...and they give you intermittent problems.
You will need a small precision screwdriver to close the gaps on the connector.
If that doesn't help...it's the Maf.

Post by **abscate** » 18 Feb 2019, 12:31

Here is a thread written by an idiot who didn't pay attention to his induction hose clamps - and a classic case of why unplugging the MAF isnt a good diagnostic for the MAF

viewtopic.php?f=1&t=76489&hilit=80+induction+failure

Post by **Eddystone** » 18 Feb 2019, 12:57

abscate wrote: ↑18 Feb 2019, 12:31 Here is a thread written by an idiot who didn't pay attention to his induction hose clamps - and a classic case of why unplugging the MAF isnt a good diagnostic for the MAF

viewtopic.php?f=1&t=76489&hilit=80+induction+failure

Idiot, fer sure. I've long past stopped listening to that guy, anyway...

This car is a non-turbo, so there are no loose boost hoses. There's just the on b;lack hose going to the intake which I replaced recently. I checked it anyway.

I will check the cleanliness and tension on the connector contacts as suggested.

I did order a new Bosch MAF sensor from Amazon for $143.00 and free shipping via Prime. If I don't need it, UPS will pick it up from my doorstep and take it back. Should be here Wednesday, and I don't plan on using that car for a couple of days. Nice having a simple old 93 940 sitting around sometimes. Next time registration is due on that one, it's antique plates.

Regarding idiot moves, when I reassembled my T5 and tested it, it ran like a champ until there was a POP and nowhere near as much power. I had not tightened the boost hoses enough, though I thought they were pretty tight. Nope. This actually happened to me twice within half an hour while I was testing the car down the road from my house. My hose clamps were nowhere near rusting through, but I did order some nice stainless ones that are the exact size and width.

Post by **misha** » 18 Feb 2019, 13:01

Make sure that it have the same Bosch mumbers 0 280 217 107,like old one.

Post by **Eddystone** » 18 Feb 2019, 13:13

misha wrote: ↑18 Feb 2019, 13:01 Make sure that it have the same Bosch mumbers 0 280 217 107,like old one.

Definitely the right part number ordered. My 1999 T5 comes up with a different part number, so it's not one size fits all.

Amazing that the "supposedly" same part can be offered for sale on the web ranging from $20 to $348. I will do some maintenance on the connector as you wisely suggested (I've done that with many connectors over the years). There are a dozen different Bosch part numbers that Amazon seems to think are compatible with my car, so I went to the Bosch site and searched. As I said, the one on my car has markings painted on it showing that it was a junk yard pull some years ago.

Bosch Original Equipment 0280217107 Mass Air Flow Sensor (MAF) - New $143.00

Post by **misha** » 18 Feb 2019, 13:22

'99 and '00 have totally different engine management ME7...and some of them use Denso sensors....so '99 & '00 use different Maf.

Post by **Eddystone** » 20 Feb 2019, 07:48

Follow-up: Ordered a Bosch MAF sensor from Amazon. I have a Prime account and paid an additional $3.99 for next day shipping. Believe it or not, it showed up the next morning via UPS at 10:30 am. That's hard to beat. The sensor appears to be Bosch. It's in a Bosch box. What more can I know regarding whether or not it is authentic? $143 is a pretty good price.

So, I inspected the connector which was, indeed, grungy with a bit of corrosion and what appeared to be grease. I hit it with some contact cleaner spray which immediately globbed up due to the 37 F temperature. Cleaned it up with some micro-Q-tips I have, and it looked shiny, but slightly wet. Plugged it into original MAF, and the car started up but ran rough. There's a possibility that this sensor is not completely bad, but I am putting off any experiments with it until the Spring.

Installed new Bosch MAF. Car immediately started, seemed slightly rough, but there may have been unburned fuel in the cylinders or the computer might have had to adjust to the new sensor. Took it for a ride, and it's now running smoothly. Took it out and tested it under the conditions where it was stalling out before, and engine seems rock solid. So, it seems as if it was a sensor issue, and it seems to be fixed. I will play with the old sensor in the Spring and decide whether or not it is worth carrying as a spare.

Post by **misha** » 20 Feb 2019, 09:20

Remove negative battery cable for 15 min in order to reset ecu and bad fuel trims.
Perform re-learn procedure(to speed up ecu re-learn) and that's it.

Post by **abscate** » 20 Feb 2019, 11:16

added part numbers to thread

1275749, 0280217107, W0133-1600936

(Irrelevant boast on this thread - the 1999 on MAF is only $90 at FCP - is this the rare case where the bastard part is cheaper?)