fst100

iTrader: (5)

recently this p0101 pops up after either cruising or after i do a few WOT hits. when this code is either pending or comes on, the car sputters at cruising speed, especially at freeway speeds (60+ mph) and keeping the shifter in D2 or 3rd gear helps getting the car to not sputter as much. at this point my AFR is pegged at 16.00 at idle and cruise.

also notice that my wideband at the top of the shift (2nd gear
) goes from 12.x and totally leans out to 14-15.xx . no KR. another thing i notice is that my MAF frequency hits 10.5k hertz which is rare seeing im only LBO.

i did pick up a new MAF sensor but still same issue. using my torque app, if i clear the DTC code the car magically runs like a champ but after driving it (AFR readings normal), the DTC p0101 will come on again as pending and the sputtering continues (AFR pegs lean at 16.xx).

my mods are intake and headers. im running 42.5lb gtp injectors with a 255lph walbro fuel pump.

fst100

iTrader: (5)

bump, anyone?

ChopperDoc

It sounds like your getting an airflow miscompare error. If VE and MAF are not "close enough" then that code will set. Check under your MAF diag to see at least what I'm talking about. I wouldn't make any changes there though. Get your VE squared away and you'll never see it again. And if you do, then at least the VE is squared away and it will run perfectly fine, MAF or not.

fst100

iTrader: (5)

[QUOTE=ChopperDoc;19826679]Check under your MAF diag to see at least what I'm talking about. I wouldn't make any changes there though.QUOTE]
ChopperDoc, what (table) do you mean by the MAF diag? do you mean the airflow frequency?

ChopperDoc

[QUOTE=fst100;19826681]No, it's under engine diagnostics, under the MAF tab (where you go to fail it for SD). You'll have to be in advanced editor view to see it.

fst100

iTrader: (5)

okay, that was the other table I was curious about. I had read some ppl increase that particular table, the Max Delta MAF P0101 table by 10%-20% but that's mainly regarding cam swapped applications (again from what I was able to dig up).

ChopperDoc

Shouldn't need to do a lot to that table if your VE is good.

fst100

iTrader: (5)

gotcha, thanks. my VE table is whatever was set at the factory. I tune is mainly via OLMAF, so the MAF and a wideband.

ChopperDoc

You can bump that table up a bit in the meantime, because you do have different injectors. All airflow values are based on injector flow rate. Make sure you have ALL of the injector data for your injectors. Offset, min, default, etc. You will probably still get a code though, since VE is still stock. Once VE is good, you won't care if the MAF fails.

fst100

iTrader: (5)

thanks, i'll go back and double check the injector tables. I compared what changes were made back on my old firebird build as that also were on gtp injectors.

ChopperDoc

You know, if it were me, I'd be using trims too (CL) since it lets the computer make appropriate changes to fuel. If your cam is too rowdy for the STFTs to work at idle, they can be disabled using PE at idle. Just set PE TPS enable to 0 up through about 1200 rpm, then set the eq table to 1 through 1200. That way it idles in OL, and over 1200 it goes back to CL. Might as well since you're using MAF anyway.

fst100

iTrader: (5)

I'm running stock cam :-)

ChopperDoc

Then STFTs should work fine all the time outside of PE. The PCM will get its numbers for PE in OL, which is why you should really focus on getting that VE table squared away. That's the order that tuning is done in... VE first, then MAF, then spark.

fst100

iTrader: (5)

i'll take a peek at the ve table and attempt to tune that accordingly. thanks for your help!

ChopperDoc

There are some good guides on hp tuners for doing the VE. Just be patient, take it slow, try not to make huge adjustments when you start getting close. Keep the table as smooth as you can. Smooth it by hand (if needed, I do this on mine) and use the smoothing feature between cells you can't hit so long as you have data on either side.

Also, my technique is to set all my OLEQ ratios to 1.0 above 176*. Leave it alone under that, but it helps get your VE dialed in faster, since commanded fuel should be stoich everywhere except when in PE. Leave PE enabled and follow the guides. Shoot for 12.5 afr on an N/A car for PE.

fst100

iTrader: (5)

question though, if it is due to the large difference between the MAF table and VE table, would it cause the extreme lean condition at top of WOT and hit the MAF range higher than it use to? IIRC my MAF frequency hit a max of 9500. currently with this issue it hit 10500 which is mainly around heads and/or cam territory.

weather here has been rain/sleet/snow so I haven't a chance to do a write and drive the car around. :-\

ChopperDoc

What are your power enrichment settings? You should be in PE with WOT.

fst100

iTrader: (5)

IIRC 1.14 or 12.8

fst100

iTrader: (5)

WB actually reads ~12.5 before this issue came up.

ChopperDoc

This really sounds like a VE/MAF calibration problem. Not 100% positive on this, but for PE mode the PCM reverts to the VE table for fuel numbers. I am sure that it goes open loop in PE though. Just not sure which table the PCM uses for a/f.

I do know calibrating them both will solve your problem though. Don't do anymore WOT until you get those tables straightened out...