pp2000 maf sensor readings

[soretoez]

been having a play with the pp2000 trying to suss it out managed to work out some off it managed to turn off the overspeed warning and erased about 15 error codes most off which haven't returned yet, so that's a good thing.

The reason for this topic is maf sensor reading what should it be I know it varies but in what ranges should it be? when I start the car it reads about 400 ish + or - then something clicks in the engine bay assuming egr because the maf reading drops to about 224 I haven't check it while driving yet but do they sound about right and it just needs a good clean?

[stevewalsh]

I don't know what the readings should be,I use a different Diagnostic system and don't have any fault codes on, but I occasionally pull my MAF sensor out and give it a clean with solvent spray and airline, It doesn't do it any harm, Mine is on original MAF with 274000 miles on it.

[GingerMagic]

No harm in cleaning it, but it's very fragile, do be gentle. I've used a contact cleaner, also brake cleaner, as neither leave a residue...

250 at stand still sounds about right, 400 is okay too but anything nearer 600 before driving is a bit high...

[soretoez]

Cool i'll get some contact cleaner today and give it a clean, the readings were slow to change when I reved it could be covered in schmoo.

[Doggy]

The other thing you can observe with a failing MAF is the value reducing initially as you increase speed from idling. A healthy one has its lowest reading at idle and increases with engine speed.

[soretoez]

I think mine is just slow to respond either that or the laptop is, i'm not sure if i'm plugged in to a usb 1 or 2 socket does that make any difference?

[GingerMagic]

It could be the laptop....
My first one was okay to start with but got slower and slower over the years - to the point I used to run out of small talk during a global scan....
Laptop number 2 is much better, slightly newer but way quicker - I'm still using my original diagnostic equipment, so for me it was the laptop that was slow.

[soretoez]

I'll have to have a dig around on the specs it was fresh install of win7, so not slowed by the usual build up off crap they seem to collect it exceeds the specs needed by a mile.
I only got the pp2k Saturday so not really sure how quick it runs i'll have a mess around try a few things out.

[mjb]

It's been a while but I'm almost certain PP2000 like most diag interfaces is just a serial over usb interface running at a relatively low baudrate - certainly nowhere near the 12Mbps capability of USB1.0.

Also, like many other dealer diag interfaces, it's slow as hell to do most things - especially probing for ecus (global scan) and reading parameter values. I think last time I used it, it took a couple of seconds to refresh the engine ecu parameters page

Depending on many factors including age and build configuration, the car's internal busses run at a handful of kilobits/sec and diag data always has lower priority than everything else, so it's never going to be fast, especially with a running engine

[soretoez]

Yeah it probably is fine I cleaned the maf the car starts picking up at about 1800 now instead of 2000 and a bit.

I'm not bothering with the error codes now I think I'm just chasing ghosts. Most of them center around the dpf I reset the counters and in my last fill up it injected some and it says the last regen was done 250 miles ago and i've done 600 since I bought it.

I've got to check engine mounts I think maybe alot off the labouring feeling and noise may be down to a soft or duff mount allowing more noise into the cabin.

[fattail95]

Here is the MAF readings from an ECU log recorded from my 406 during a drive. I did several hard runs from 1500rpm to 4500rpm, and plotted the results: