GM MAF & MAFT in changing weather conditions

[Nofear20]

Went through 10+ search pages and couldn't find anything about this.

My question is, how does the gm maf, and maft setup work in different weather conditions? I was told in different weather conditions such as rain, the intercooler will suck up small amounts of water and go through the gm maf, and greatly change the tune of the car and make it run bad. What is everyones opinion on this?

 

[dsmfa9nutter]

Your intercooler shouldn't be sucking up water unless it has holes in it. Moisture from the air can affect the MAF. Tune it on a nice day and deal with the odd stumble when it's pouring rain out. Nobody races in the rain anyways.

 

[cbrfrenzie]

I do know that the GM MAFT outputs a constant 80 degrees F to the ECU, therefore changes in Intake air temps will not be compensated for at the ECU.

 

[talon187]

take it form exp im running one with a safc2 and ive had issues with temp change i havent really driven my car in the rain much but when i have i have not got on it and it ran fine

 

[Avionixx]

I've been running a GMAF in a blow through configuration for over 3 months now and if anything, the car drives better than it did with the 1G MAS. There is some very minor stumbling on cold days (below 50 degrees here in California) while the car is warming up, but it's almost unnoticeable unless you decide to punch the throttle (who'd do that before the car is warmed up though?). I've had no issues with rain and the Bay Area was getting hit with some good storms a few weeks ago. I've yet to drive it in summer heat, but we'll find out soon enough.

I think the only time I would recommend against it if you live in an area that experiences extremes with the weather; either with close to subzero temps or really oppressive heat.

 

[bastarddsm]

I do know that the GM MAFT outputs a constant 80 degrees F to the ECU, therefore changes in Intake air temps will not be compensated for at the ECU.

That is exactly what makes the maft a pos...granted it will work great on a race car but i certainly wouldn't run it on a dd. The factory computer pulls some timing in the case of extreme IAT temps, along with the fuel issues. Having a set up like this is like having your car carburated. You need to tune it everytime the weather changes. I wish i had more time on my hands, I think one of these could be modded to use an IAT in the uicp. This would make it a really powerfull tool.

With some time it probably wouldn't be hard to construct a circuit that mimics the output of the stock maf, but uses the GM MAf to generate it along with a MAP sensor and a IAT sensor. Then you could use DSM Link to tune or eprom or afc, and not have to re tune everytime the weather changed..

I do have a flow bench and lots of test equipment.....anyone got a 1g maf and a GM Maf they wanna donate to science??

 

[91TsiTalon]

Your intercooler shouldn't be sucking up water unless it has holes in it. Moisture from the air can affect the MAF. Tune it on a nice day and deal with the odd stumble when it's pouring rain out. Nobody races in the rain anyways.

Nobody thats FWD races in the rain...

 

[bastarddsm]

Haha we do... we race to see who can get there car into 5th spinning the tires first..haha

 

[91TsiTalon]

I should have said "successfully"...because i think you meant attempts...

 

[Nofear20]

That is exactly what makes the maft a pos...granted it will work great on a race car but i certainly wouldn't run it on a dd. The factory computer pulls some timing in the case of extreme IAT temps, along with the fuel issues. Having a set up like this is like having your car carburated. You need to tune it everytime the weather changes. I wish i had more time on my hands, I think one of these could be modded to use an IAT in the uicp. This would make it a really powerfull tool.

With some time it probably wouldn't be hard to construct a circuit that mimics the output of the stock maf, but uses the GM MAf to generate it along with a MAP sensor and a IAT sensor. Then you could use DSM Link to tune or eprom or afc, and not have to re tune everytime the weather changed..

I do have a flow bench and lots of test equipment.....anyone got a 1g maf and a GM Maf they wanna donate to science??

Ive been planning on getting a maft gen 2 setup for my DD.. but after reading that... I am not so sure.

 

[talon187]

like i said before im not to pleased with mine im thinking of geting a maft pro but id like to talk to someone whos running it or has. the maf pro uses a gm map sensor and air temp sensor and you can program with a laptop. on another note i didnt notice a issue with it really when i had it with the stock injectors as soon as i put bigger ones in and uped the boost is when i noticed issues

 

[Nofear20]

Talon187... Exactly what kind of issues do you have

 

[talon187]

il drive the car for a day or two and it will be fine. then it will run eaither to rich or to lean and when i mean rich i mean PIG rich and i have to tune with the safc2 all over again. if your going to just use a maft to tune with anything else well ha good luck.it would take FOREVER to tune with just the maft my advice to you is get a maft pro yes its more money but you'll be 100x happier you did

 

[blownturbotsi]

On my previous tune with the Maf-T only, I had no problems what so ever. I had all of the mods in my profile except a stock ECU and 660's. I never had trouble with it stumbling, running crappy or anything of the sort. Up here in northern NM, the weather changes more than the gas prices. It could be 20 degrees one day and 65 the next. I drove it during dead 100+ degree summers down to the teens with snow and ice on the road. Maybe I'm just fortunate. :dunno:

 

[JayRolla]

My few people I know that run the maf-t with dsmlink have no issues at all. If your using it alone or with an safc in drastic weather change you may have to do a little tuning. Here in CO it can be 80* in the afternoon and if a storm rolls in it can be 30* or less. My buddy had to do a little tuning but it wasnt much of an issue. I myself will be installing one in a few days so I will see how it does.

 

[turbotsi90]

is it pretty easy to tune?

 

[95CarbonEclipse]

Is anybody that's claiming to have had trouble with their MAFT setup running the MAFT Gen II? I'm curious to know if the Gen II being hooked up directly to a wideband alliviates the fine tuning/readjusting during changing weather conditions since you can set an A/F ratio and the Gen II will hold it there?

Also, someone posted that the GM MAF sends a constant signal of 80*. What about running a different MAF, like say... an EVO MAF??

 

[bastarddsm]

ehh it doesn't work like that. its the box tht sends the 80 degree signal. an evo MAF is just like factory and uses a HZ signal, so only adjustments to the rom's airflow map need to be made.

some of you guys must be lucky. it seems the way it works it needs some compensation for temp and baro. pressure, with a MAFT there is no compensation for this. Unless I am mistaken the heat transfer properties of air do not depend of the density of air. So the GM MAF only measures the volume of air flowing through it, without the pressure and temperature, it cannot know what the mass of the air is, which is what the computer needs to know.

anyway, unless you enjoy tuning your car everyday, the MAFT is not a very wise choice for a street car.

 

[95CarbonEclipse]

But again... wouldn't the Gen II version, with it's ability to monitor and adjust to your wideband reading, alleviate this?

 

[Nofear20]

But again... wouldn't the Gen II version, with it's ability to monitor and adjust to your wideband reading, alleviate this?

I am also wondering about this

 

[JeffGST]

Common guys. It's not to difficult to understand.

The stock MAF measures 3 things
AIR VOLUME / AIR TEMP / AIR BAROMETRIC PRESSURE

Then the ECU uses (PV/T = MASS) to calculate MASS.

The GMAF measure only 1 thing. It measures MASS directly. So when the ECU receives it's signal from the GMAF it is measurement of MASS and not Volume. Therefore the Translator MUST hold barometric pressure and air temp constant so that the (PV/T =M) calculation is not corrupted. We already have M directly from the GMAF.

So anyone who says that air temperature affects the MAFT reading does not understand how it works. The MAFT takes into account high temperature and low temperatures by calculating MASS, not volume.

 

[95CarbonEclipse]

That makes sense.

 

[blownturbotsi]

anyway, unless you enjoy tuning your car everyday, the MAFT is not a very wise choice for a street car.

I really disagree with this and I think it's misinformation.

 

[Crazyjoker77]

I really disagree with this and I think it's misinformation.

+1 Ive been driving on my safc/maf-t 2.02 for over 2 years now with very little problem... Also i got a huge improvment in my gas miliage compared to the stock mas with my BOV venting