jamieparr

Hi all

I believe I have a suspected MAF issue, I have experienced MAF issues in the past and am pretty certain I am hitting the same issue.

My question; is there anyway to log whether the MAF is having an issue, I am experiencing a slight loss in power at high revs and a dragging feeling. If I log the MAF via OBD should I see a drop or spike in the stats? Common sense says that I should...

Thanks in advance

Jamie

JDM_Stig

iTrader: (3)

what car and year ?

jamieparr

wrx 2005 blob eye

Shaun

MAF voltage should be increasing with RPM (through a gear @ WOT), up to peak airflow and then tail off slightly.

jamieparr

Thanks for the info guys, I took it for a quick run and monitored the MAF readouts. I hit another dragging spot in my acceleration, I kept it going for a bit to get a good reading and the MAF readings tabletopped at 82g/s. When I got back I also read codes "p0102 Mass or Volume Air Flow Circuit Low Input" & "p0113 Intake Air Temperature Circuit High Input"

This looks to me like the MAF needs replacing, however any second opinions are welcome, anything else I could try before doing this?

Here is some of the output of my run, the yellow line shows a clear tabletop (by the vertical white marker)



Thanks

sac

iTrader: (1)

hi don't mean to but in but do u no how to check my maf on a 94 wrx. (no obd)
not sure if it crap fuel or somthing else. poor pick up and Missy when cold and not boosting as it should when warmed up.

Shaun

Jamie,
Was that a WOT run in a single gear as the sampling "appears" to be all over the place?

Sac,
I'm not sure if there is some form of resistance check you can do. Someone else maybe able to enlighten you on that one.

sac

iTrader: (1)

thanks shaun, this problem started when i filled up at different garage,shell i think vpower, what fuel should i b using. getting mixed views. 94 wrx with z4,td05,headers,decat,s/s system,hks filter,dump valve. the guy i got the z4 off said that the boost had been mapped. but i thought z4s were not mappable.
what fuel.? sac

Shaun

Sac,
You really need to take it to a "Specialist" in my opinion, especially since you have put one of the best, if not the best pump fuel in the car (and you're getting issues). Unless it was a bad batch of fuel, I very much doubt VPower will be your issue.

You sure it was VPower and not their normal 95 Unleaded?

sac

iTrader: (1)

100% vpower checked my receipt. not sure on the station people have bitched about it before.

jamieparr

Hi Shaun

I put it in third and put my foot down over several attempts to hit the issue, the point at which it tabletopped was when I experienced the issue

jamieparr

The entire readout is me pulling off and then hitting the motorway and then stopping

Shaun

I'm sorry, the information you have provided is not that clear.

You need to either zoom in or only sample one WOT run through the revs in one gear.

sac

iTrader: (1)

hi shaun just thought i would let u no all sorted now. I drained all of that vpower out and replaced it with normal unleaded and after a short run back to normal, crisp sharp boosting and no missing. so maybe ace cafe?