---===The Official MAFT-Pro Thread===--- - Page 247 - 3000GT/Stealth International Message Center

msassoon · 10-09-2007, 02:29 AM

Don't thank me, thank Stef at M&S, it was his idea!

EastWingedBeast · 10-09-2007, 05:24 AM

My idle AFR is a bit eratic. It wanders slowly from 13'ish to 15'ish, up and down, up and down, up and down.

I'm running a hot wired Supra fuel pump and a standard FPR. Could the FPR be having trouble with the improved fuel flow, and therefore running higher pressure at idle?

Also, whatever I set WOT AFR tracking to, it always manages to run 11'ish. Which could also point to fuel pressure too high?

Paul.

Highboosted · 10-09-2007, 08:33 AM

Quote:

Originally Posted by EastWingedBeast

My idle AFR is a bit eratic. It wanders slowly from 13'ish to 15'ish, up and down, up and down, up and down.

I'm running a hot wired Supra fuel pump and a standard FPR. Could the FPR be having trouble with the improved fuel flow, and therefore running higher pressure at idle?

Also, whatever I set WOT AFR tracking to, it always manages to run 11'ish. Which could also point to fuel pressure too high?

Paul.

How close is you idle tune? (look at correction factor)

Yes, but it's not really a problem because you can tune around it.

Again, whats your correction factor, I think your tune is far enough off that your factors are maxed and it can't bring the AFR to where you want it.

EastWingedBeast · 10-09-2007, 10:34 AM

Quote:

Originally Posted by Highboosted

How close is you idle tune? (look at correction factor)

Yes, but it's not really a problem because you can tune around it.

Again, whats your correction factor, I think your tune is far enough off that your factors are maxed and it can't bring the AFR to where you want it.

I'll need to check the correction factor tonight.
However, it manages to get into the same ball park as 14.7AFR, it just wanders around. I'll get the figures out of the Pro tonight, and get back to you. Thanks for that.

What AFR are you targetting at WOT? Boost level?

Paul.

Barefoot · 10-09-2007, 09:27 PM

So, I have been having this problem since I first installed the maftpro, replaced the maftpro wire harness with a new one bob sent me. still having the problem though, and it is really starting to annoy me.

I think It is possibly part of why i cannot get my tune correct to run any good ammount of boost..

anyways, everytime I touch the unit or it gets jarred at all.. the tune goes to shit.

TurboBob · 10-09-2007, 09:42 PM

Quote:

Originally Posted by |4x4 NV|

So, I have been having this problem since I first installed the maftpro, replaced the maftpro wire harness with a new one bob sent me. still having the problem though, and it is really starting to annoy me.

I think It is possibly part of why i cannot get my tune correct to run any good ammount of boost..

anyways, everytime I touch the unit or it gets jarred at all.. the tune goes to shit.

Hmm....

Well, try bending each harness by itself. then each wire by itself so see if you can isolate the individual wire.

also see if other movements of the harness might cause it. Meaning that make sure the spliced end of the harness is not intermittant.

can you watch the sensor page and see if you can see what data is changing.

try unplugging and re-plugging the harnesses about 10 times and see if the symptom gets better or worse.

Bob

Quick Vr4 · 10-10-2007, 03:51 AM

i actually ended up having to solder each wire onto the board and use a different type of connector. That fixed my problem

EastWingedBeast · 10-10-2007, 05:16 AM

Quote:

Originally Posted by Highboosted

How close is you idle tune? (look at correction factor)

Yes, but it's not really a problem because you can tune around it.

Again, whats your correction factor, I think your tune is far enough off that your factors are maxed and it can't bring the AFR to where you want it.

Highboosted,

My correction was at -12 ish when AFR tracking on part throttle, so I took some fuel out and now it wobbles around the 0.0 mark. Sometime -6 or -7, sometimes +5 ish. Still have the idle wandering problem.

Anyone reckon my fuel pressure is wandering too? Am running a hotwired Supra fuel pump on a standard FPR.

Cheers,
Paul.

Highboosted · 10-10-2007, 08:38 AM

Will it idle stable with PT tracking disabled? You can adjust the gain and that affects how fast the PAFT-Pro tries to track idle, but since there is very little airflow at idle, just raising too much could make it worse, so try lowering it also and find a sweeet spot. your fuel pressure will wander if the VAC is wandering, which it will do when your idle speed is bouncing, but that will happen on any FPR.

TurboBob · 10-10-2007, 12:19 PM

Quote:

Originally Posted by EastWingedBeast

Highboosted,

My correction was at -12 ish when AFR tracking on part throttle, so I took some fuel out and now it wobbles around the 0.0 mark. Sometime -6 or -7, sometimes +5 ish. Still have the idle wandering problem.

Anyone reckon my fuel pressure is wandering too? Am running a hotwired Supra fuel pump on a standard FPR.

Cheers,
Paul.

if you are overrunning the regulator at idle, the fuel delivery will be non-linear. that can cause tuning headaches and AF ratio inconsistencies.

Bob

10-09-2007, 02:29 AM	#2461 (permalink)
msassoon Forum Member Join Date: May 2004 Location: Berkshire, England Drives: GTO SC ATX Trader Rating: (1)	Re: ---===The Official MAFT-Pro Thread===--- Don't thank me, thank Stef at M&S, it was his idea! __________________ Black 1991 Ripp Modds Supercharged GTO DOHC MAFT Pro running speed density. Erebuni front bumper and side skirts Racetech Exhaust. EK2 shorties and 3SX Downpipe Custom transmission and oil cooler Import Precision VLS doors 18" Chrome VR4 wheels and Chassis Dynamics Lowering springs '99 Sail panels Lightened crank pulley EK2 fuel rail adapter. Underbonnet bling Too much custom stuff to mention

10-09-2007, 05:24 AM	#2462 (permalink)
EastWingedBeast Forum Member Join Date: Sep 2007 Drives: GTO Twin turbo Trader Rating: (0)	Re: ---===The Official MAFT-Pro Thread===--- My idle AFR is a bit eratic. It wanders slowly from 13'ish to 15'ish, up and down, up and down, up and down. I'm running a hot wired Supra fuel pump and a standard FPR. Could the FPR be having trouble with the improved fuel flow, and therefore running higher pressure at idle? Also, whatever I set WOT AFR tracking to, it always manages to run 11'ish. Which could also point to fuel pressure too high? Paul.

10-09-2007, 09:27 PM	#2465 (permalink)
Barefoot Racing Join Date: Jan 2003 Location: Ga Tech Drives: 92R/T - converted ;) Trader Rating: (31)	Re: ---===The Official MAFT-Pro Thread===--- So, I have been having this problem since I first installed the maftpro, replaced the maftpro wire harness with a new one bob sent me. still having the problem though, and it is really starting to annoy me. I think It is possibly part of why i cannot get my tune correct to run any good ammount of boost.. anyways, everytime I touch the unit or it gets jarred at all.. the tune goes to shit. __________________ 92 Dodge Stealth R/T AWD/TT (TD05) converted ( 11.894 @ 120.56 - 18 psi -> Video )

10-10-2007, 03:51 AM	#2467 (permalink)
Quick Vr4 Forum Member Join Date: Oct 2002 Location: Southern California Drives: 91 3000gt VR4 Trader Rating: (11)	Re: ---===The Official MAFT-Pro Thread===--- i actually ended up having to solder each wire onto the board and use a different type of connector. That fixed my problem __________________ R.I.P 20g VR4

10-10-2007, 08:38 AM	#2469 (permalink)
Highboosted king of ghetto Join Date: May 2004 Location: St. Louis Drives: '94 Stealth Turbo Trader Rating: (29)	Re: ---===The Official MAFT-Pro Thread===--- Will it idle stable with PT tracking disabled? You can adjust the gain and that affects how fast the PAFT-Pro tries to track idle, but since there is very little airflow at idle, just raising too much could make it worse, so try lowering it also and find a sweeet spot. your fuel pressure will wander if the VAC is wandering, which it will do when your idle speed is bouncing, but that will happen on any FPR.

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