MAF part number

[Avendit]

Hi all,

I got a new MAF off Mr T about a month ago after apparently killing the last one (lesson - don't clean your MAFs, just get new ones), and it was certainly much better than the broke one it replaced. But then I started monitoring the LTFT and STFT and noticed some situations where the ECU was pulling upto 30% fuel!! This is waaaaay up on where it has been the last 3 years, with it stable inside -10 to +10.

So I did some re-jigging of the closed loop tune to bring the trims back to something more reasonable, but I noticed that the same error % on the open loop WOT - sitting at about 10:1 AFR.

I began suspecting the MAF so checked the part numbers and found that although my old MAFs are PN 22204-22010, the one MR T had supplied was 22204-0J010. A lookup on line shows the new part would more normally be associated with a 1ZZU, not a 1ZZFE.

When challanged on the Mr T says that the new part is a replacement part number, and correct. Can any one confirm this for me? Is anyone using a 0J010 and its OK?

I'm going to swap an old spare in this evening and see what happens, but any other ideas or suggestions very much welcomed.

Thanks
Avendit
(1zz C2 turbo @250bhp)

[jlitman]

If you're going to clean it, use the CRC MAF sensor cleaner spray, which won't damage anything, and don't try to swab it with any objects.

part number I have is: 22204-0D030

[Avendit]

Thanks jlitman, looks like they may just be interchangable throughout the range?

Since the other MAF went, starting has been much harder than it ever was. it still starts first time, but it takes a good few extra turnovers on the starter before it catches. Can you think of anything else I should look at?

[jlitman]

Thanks jlitman, looks like they may just be interchangable throughout the range?

Since the other MAF went, starting has been much harder than it ever was. it still starts first time, but it takes a good few extra turnovers on the starter before it catches. Can you think of anything else I should look at?
Does it crank okay, but just won't turn over? Stock fuel pump or aftermarket?

High fuel trim at idle could make harder it turn over too. If not caused by the MAF sensor, could be the primary O2, which might be worth replacing if over 60K miles. They get laggy over time.

[Avendit]

Its an after market pump, and trims are fine now, just the map is very different to what it was before to make it so.

Instead of crank crank vroom, its more like crank crank crank crank crank vroom. I've swapped the battery just in case, and it cranks quicker now, but still takes just as long. Oddly some times its fine, and I can't see any rhyme or reason to the pattern either - its not length of time sitting, or external temps or anything. I'll get the new pump install checked.

Good idea on the o2. Car is just coming up 70k miles, 40k of which have been turboed.

please excuse the over use of technical terms in this post :D.

Avendit

[Avendit]

So, not sure if the newer part is stuffed or just different, but the car is much happier with an old MAF in. Now just to talk to MrT and see if the new part is considered borked, or this is the new reality and I should just tune to the new MAF. It did seem slower too tho.

Datapoints, taken at idle using volt meter in the emange:

rpm | Old | New
------------------
1000| 1.17 | 1.25
3000| 1.70 | 1.80
5000| 2.07 | 2.20

and using the 'old' MAF, doing 2200rpm, WOT @ 35mph in 4th I see 2.5v (this just to let me do some graphs tomorrow really)

some thinking to do here.
Avendit

[Avendit]

Thats about 7% out, which doesn't seem too bad, yet it makes the difference between 10:1 AFR and 12:1 AFR at WOT!

[Aka Rafa]

part number for the maf is # 22204-22010

[johnnyGTA]

^ yup, I have an extra one if you want it

[jlitman]

Its an after market pump, and trims are fine now, just the map is very different to what it was before to make it so.
That sounds familiar. Is it going lean under boost and does it seem to start easier cold than hot?

See further http://www.newcelica.org/forums/showthread.php?t=302576

[Avendit]

Not fixed the fuel pump problem, MrT sold me the wrong gasket first time I think (assembly seal rather than pump seal). However, about the MAF - I applied a -7% adjustment across the airflow adjustment map while running with the new MAF and the car is a whole lot happier (once its started at least!)

Thanks for the help,
Avendit