3vze VAFM help....
04-06-2005, 08:53 PM
#1
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3vze VAFM help....
The Toyota Factory Service Manual shows the VAFM as having 7 pins from left to right they are:
"Fc" "E1" "E2" "Vc" "E2" "Vs" "THA"
I think that
Vc = voltage constant
E2 = ground
THA = Air Intake Temp
Fc = if the throttle plate is open or closed (not sure here)
But what do Vs and E1 do?
Im kicking around the idea of a MAF conversion but would like to know what each and every wire does as well as HOW the vafm works...
"Fc" "E1" "E2" "Vc" "E2" "Vs" "THA"
I think that
Vc = voltage constant
E2 = ground
THA = Air Intake Temp
Fc = if the throttle plate is open or closed (not sure here)
But what do Vs and E1 do?
Im kicking around the idea of a MAF conversion but would like to know what each and every wire does as well as HOW the vafm works...
04-06-2005, 09:04 PM
#3
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3vze's do not have MAFs they have VAFMs which severely restrict the airflow..... Im kicking aroudn the idea of a MAF conversion but before I do anything I'd like to know exactly what each of the 7 wires is for and how the vafm functions...
04-07-2005, 08:54 PM
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Sorry don't have any help for you, mostly just a bump. Are you planning on controlling the MAF with your stock ecu, or with an smt or something? I am very interested if you can get this to work. good luck 
04-07-2005, 09:42 PM
#6
E1-Fc is the fuel pump contact, keeps the fuel pump running while the engine is pulling air past the AFM. E2-Vs has the main air flow reading:
http://www.4crawler.com/4x4/CheapTricks/AFM/index.shtml
http://www.4crawler.com/4x4/CheapTricks/AFM/index.shtml
04-07-2005, 10:15 PM
#7
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Thread Starter
So measuring at the connectors we should get this right? Please correct me if I'm wrong....im a bit slow...lol
Vc - E1 = 12vdc (12v input)
Vs - E2 = 0.2 - 4.3 vdc (AFM output)
Tha - E2 = 1 - 3 vdc (AIT)
Fc - E2 = 12vdc when on to kick on fuel pump
With E1 and E2 both being grounds and Vc being the 12v signal fed to the afm then?
Vc - E1 = 12vdc (12v input)
Vs - E2 = 0.2 - 4.3 vdc (AFM output)
Tha - E2 = 1 - 3 vdc (AIT)
Fc - E2 = 12vdc when on to kick on fuel pump
With E1 and E2 both being grounds and Vc being the 12v signal fed to the afm then?
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04-08-2005, 03:48 AM
#8
Contributing Member
There's a Supra FM that is not VAFM that supposedly puts out the same electronic info that our VAFMs put out. I'll see if I can find the info on it this evening.
04-08-2005, 09:02 AM
#9
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Im going to see how the 7mge VAFM does as far as power improvement...then from there decide if the MAF is worth it or not...I think it will be though.
So did ya find anything? If indeed a supra engine of some kind it would be from a late mkIII (though I doubt it) or a mkIV.... Now THAT would be nice - a plug and play MAF....
So did ya find anything? If indeed a supra engine of some kind it would be from a late mkIII (though I doubt it) or a mkIV.... Now THAT would be nice - a plug and play MAF....
04-08-2005, 09:29 AM
#10
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04-08-2005, 10:03 AM
#11
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Thread Starter
Yes Cebby, that is the 7mge VAFM from a cressida or a mkIII supra (where mine came from) - I got one sitting in my back seat right now waiting to go on....but it's still a vane air flow meter. A MAF like our 3rd gen brothers have would be a LOT better I would think...
Once I finish this cursed valve shimming ordeal (one is still out of spec) I need to ascertain that my truck runs ok, then my 7mge VAFM goes in. But I am still dreaming of a maf...lol
BTW have you gotten 7mge AFM in yet?
Once I finish this cursed valve shimming ordeal (one is still out of spec) I need to ascertain that my truck runs ok, then my 7mge VAFM goes in. But I am still dreaming of a maf...lol
BTW have you gotten 7mge AFM in yet?
04-09-2005, 05:28 AM
#12
Contributing Member
Sorry, couldn't find it. I think it was a link from a post in YotaTech on VFMs and MAFs. As I remember, the document was a PDF explaining the function of Toy VFM's. The type of info that a Toy Tech might need.
04-09-2005, 06:05 AM
#13
Contributing Member
Found it!
http://www.autoshop101.com/forms/h34.pdf
It's a Karman Vortex AFM and it does say that it provides the same info, but doesn't say it's plug compatible or that the ECU interprets the info the same. I think these were used on some early Supras, but when I've seen them on Ebay, they go for $100+.
http://www.autoshop101.com/forms/h34.pdf
It's a Karman Vortex AFM and it does say that it provides the same info, but doesn't say it's plug compatible or that the ECU interprets the info the same. I think these were used on some early Supras, but when I've seen them on Ebay, they go for $100+.
04-09-2005, 07:14 PM
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Bumpin' Yota is correct.
Vc is the 12v constant supply to the Vs (airflow) signal and the IAT (intake air temperature)
I would be careful just swapping in any MAF. On my 3vz-fe (If i can find it I'll look at my part number if anyone wants me to)
Toyota doesn't make a compatible AFM/MAF/MAP to swap to for us (3vz-fe atleast) AFAIK. I've talked to many Toyota engines owners of varrying type, to several real life friends that are part counter managers, and a Toyota supply warehouse itself.
The 3vz-fe AFM runs backwards. Starting at around 4.5/4.2v at idle, to 0.5/0.0v at high airflow. If a 3vz-e AFM is the same (like I said, should be) You're going to have a *very* hard time finding a better one.
Someone might wanna put a multi meter on the Vs signal and see where it idles at. (If you don't want to splice into a wire, if you cut the plastic top of your AFM off, the Vs is the one on the arm connected directly to the flap. Push open the flap and you see the brushes travel across a conductive strip. Just put negative to the body, and positive to the arm.)
On a side note, Assuming it *is* the same. You shouldn't be swapping to anything else....
1) It's all ready got a lower resistance than a typical MAF, at worse case it's the same as a gutted one. And it *should* be pleanty capable of tuning to atleast 370hp at the engine... (works for our 3vz-fe's)
2) Upgrading to a larger maf only serves the purpose of a higher resolution of tuning at higher airflows. Instead of buying a new one, just cut a big hole right behind the AFM for an "alternate route". Yes... A huge vacuum leak.
Then use XXX piggyback to tune the existing AFM signal to the driveable range. (I personally found a 1" hole to provide the most bypass, while being the easyest to re-tune)
Doing so *will* require you to retune the entire singal range (the entire analog map on an smt-6)
^^^
Which begs the question: Would a swap be easier?
No... Either way the entire thing has to be retuned, and you're going to be swapping to a non Toyota part.
Why pay for what's free to begin with???
Vc is the 12v constant supply to the Vs (airflow) signal and the IAT (intake air temperature)
I would be careful just swapping in any MAF. On my 3vz-fe (If i can find it I'll look at my part number if anyone wants me to)
Toyota doesn't make a compatible AFM/MAF/MAP to swap to for us (3vz-fe atleast) AFAIK. I've talked to many Toyota engines owners of varrying type, to several real life friends that are part counter managers, and a Toyota supply warehouse itself.
The 3vz-fe AFM runs backwards. Starting at around 4.5/4.2v at idle, to 0.5/0.0v at high airflow. If a 3vz-e AFM is the same (like I said, should be) You're going to have a *very* hard time finding a better one.
Someone might wanna put a multi meter on the Vs signal and see where it idles at. (If you don't want to splice into a wire, if you cut the plastic top of your AFM off, the Vs is the one on the arm connected directly to the flap. Push open the flap and you see the brushes travel across a conductive strip. Just put negative to the body, and positive to the arm.)
On a side note, Assuming it *is* the same. You shouldn't be swapping to anything else....
1) It's all ready got a lower resistance than a typical MAF, at worse case it's the same as a gutted one. And it *should* be pleanty capable of tuning to atleast 370hp at the engine... (works for our 3vz-fe's)
2) Upgrading to a larger maf only serves the purpose of a higher resolution of tuning at higher airflows. Instead of buying a new one, just cut a big hole right behind the AFM for an "alternate route". Yes... A huge vacuum leak.
Then use XXX piggyback to tune the existing AFM signal to the driveable range. (I personally found a 1" hole to provide the most bypass, while being the easyest to re-tune)
Doing so *will* require you to retune the entire singal range (the entire analog map on an smt-6)
^^^
Which begs the question: Would a swap be easier?
No... Either way the entire thing has to be retuned, and you're going to be swapping to a non Toyota part.
Why pay for what's free to begin with???
Last edited by Toysrme; 04-09-2005 at 07:18 PM.
04-09-2005, 07:25 PM
#16
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Thread Starter
Originally Posted by Cebby
No. My new 1UZ uses a different setup.
Originally Posted by gwhayduke
Found it!
http://www.autoshop101.com/forms/h34.pdf
It's a Karman Vortex AFM and it does say that it provides the same info, but doesn't say it's plug compatible or that the ECU interprets the info the same. I think these were used on some early Supras, but when I've seen them on Ebay, they go for $100+.
http://www.autoshop101.com/forms/h34.pdf
It's a Karman Vortex AFM and it does say that it provides the same info, but doesn't say it's plug compatible or that the ECU interprets the info the same. I think these were used on some early Supras, but when I've seen them on Ebay, they go for $100+.
04-09-2005, 07:38 PM
#17
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Thread Starter
wait - why would toyota not use our VAFM for the 7mge supra, a 220hp engine, when our VAFM can support 370hp? That does not make sense.... If someone in a 3vzfe is getting 370+ with the stock VAFM I would love to see what they make with something more free flowing at WOT.
This thing is a HUGE stricture in the air intake tract.
Im not argueing by anymeans but rather just asking.
EDIT - I just answered my question. The 3vzfe uses a big VAFM - one analogous in size to a 7mge. The pic of yours here: https://www.yotatech.com/forums/f2/perfect-power-smt-piggyback-controller-56220/
Ours is 30% smaller than yours....
We got the shaft from toyota!!
This thing is a HUGE stricture in the air intake tract.
Im not argueing by anymeans but rather just asking.
EDIT - I just answered my question. The 3vzfe uses a big VAFM - one analogous in size to a 7mge. The pic of yours here: https://www.yotatech.com/forums/f2/perfect-power-smt-piggyback-controller-56220/
Ours is 30% smaller than yours....
We got the shaft from toyota!!
Last edited by Bumpin' Yota; 04-09-2005 at 07:59 PM.
04-10-2005, 10:53 AM
#18
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Really a 3vz-e doesn't use the same part? Weird. It is a few years older so?
Well, someone check the Vs voltage on it. If it's backwards like ours is (starts at 5v idle, ends at 0-1.5 v), and you can't find a backwards MAF, there's always ours. We get over 350hp from ours before it's time to consider doing something.
If yours is backwards, and you DO find a backwards MAF, let me know LoL! I know a few people that need something with more overhead.
Well, someone check the Vs voltage on it. If it's backwards like ours is (starts at 5v idle, ends at 0-1.5 v), and you can't find a backwards MAF, there's always ours. We get over 350hp from ours before it's time to consider doing something.
If yours is backwards, and you DO find a backwards MAF, let me know LoL! I know a few people that need something with more overhead.
04-20-2005, 06:56 PM
#20
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Thread Starter
The ONLY thing holding me back is having the 3" diameter pipe mandrel bent to fit in the intake and it's my work that preventing that....
I cut into the rubber boot on my VAFM plug to take some measurements. At idle Vs is putting out 1.05 volts, gunning it makes it shoot up to about 4.3v or so.
And I was correct in that Vc was a voltage constant, but it metered out to 5 volts when using E2 as a ground. And of course there is a voltage output on the THA corresponding to the temperature. In my case it was 3.5v or so. And Fc carries 12 volts with E1 being it's ground for the fuel pump....
The 7mge VAFM should work flawlessly for normal cruising, im just thinking this may lean out the truck a bit a WOT... Time to hook up my AF meter too!!
I cut into the rubber boot on my VAFM plug to take some measurements. At idle Vs is putting out 1.05 volts, gunning it makes it shoot up to about 4.3v or so.
And I was correct in that Vc was a voltage constant, but it metered out to 5 volts when using E2 as a ground. And of course there is a voltage output on the THA corresponding to the temperature. In my case it was 3.5v or so. And Fc carries 12 volts with E1 being it's ground for the fuel pump....
The 7mge VAFM should work flawlessly for normal cruising, im just thinking this may lean out the truck a bit a WOT... Time to hook up my AF meter too!!
