---===The Official MAFT-Pro Thread===--- - Page 174 - 3000GT/Stealth International Message Center

Highboosted · 11-22-2006, 06:02 PM

Quote:

Originally Posted by msassoon

I have just installed my MAFT Pro and am still using 4.40 and the values in the quick start guide to run the car. The only change I have made is to set main scale to +30 and afterstart to 10. It started first time, but I get some odd behaviour. First, at idle, the revs stay steady with AFR at 13.5, but until it warms up, it will suddenly go very lean and then very rich and level out again. Also, when driving, as I accelerate, it will go lean (16-17:1) and then richen appropriately. I guess this is tip in, but do I set the TPS enrich, and should I increase or decrease it?
I have it installed in speed density mode on an NA DOHC GTO. I have disconnected the narrowband O2 and hooked up the pro to an AEM UEGO wideband.

Thanks

Marc

If the lean spike is instantanious, tune response. If it last more than an instant (I mean instant, like boost spike instant), then it's your tune before PT tracking fixes it. Just one question, why is your mainscale set at +30? Are you running smaller injectors than stock or did you mean to say -30?

msassoon · 11-23-2006, 06:07 AM

What happens is, I press the accelerator (hard or soft makes no difference) and the AFR drops instantly, but it then richens up straight after. So, I guess I need to set TPS Decay and TPS Enrich. I am not using the charger, so there is no boost at the moment.
The mainscale is +30 on standard injectors. I do have a number of mods for the intake and exhaust that would probably cause some extra fuel to be pulled, but I have to admit I am not sure why I have it that high. If I reduce it, I get leanness at idle.
I am also not sure about the three load pages. It seems to indicate that they affect the amount of air on boost, but I have no boost. Should I reduce Hi and Mid Load Pt values to account for lack of boost? I would then increase them with the cahrger, but I want it sorted as standard first.
For the mods, I have a Mongoose exhaust, 3SX DP, Ek2 Header on the exhaust side. Intake has a 3" intake from filter to TB and a VR4 plenum. The injectors are still 220CC and Fuel pressure is 43psi.

Highboosted · 11-23-2006, 11:19 AM

you'll just tune with the low table for now...leave the mid and high at 0.

There still should be no reason you need to ADD 30% more fuel to a basically stock car....unless something is wrong with your connections or something.

TurboBob · 11-23-2006, 10:28 PM

There is something out of sorts with your setup. The stock ECU will figure out a way to idle even if the MAF signal is way out. But once you step into it the ECU will try to use the MAF signal.

Do you have a logger? Look at MAF Hz, BARO, Air temp.

What does FO read (on the Pro) at idle, MP? RPM? AFL? TPS?

You should tune the mainscale to get it to drive decently, and then tune with the high/mid/low. With stock injectors, if you find that you are adjusting a lot (more than 15%) then look into connection or setup issues.

Bob

msassoon · 11-24-2006, 01:48 AM

Ok, I will look into this. I am running speed density by the way if there was any doubt. It just seems like the tune is going lean expecting boost where there is none. I may be wrong. I will run the datalogger (TMO) and see what is happening. I just had the ECU rebuilt, and that is running fine, but I agree that 30% is very high.

msassoon · 11-24-2006, 02:10 AM

Just to clarify, I set the mid and high settings to 0% across the board? Not the kPA activation points? Also, what are TPS enrich, TPS Decay and MAP Enrich measured in? % or some other value? I increased my TPS enrich to 1.3 today and it had no effect.

Highboosted · 11-24-2006, 08:21 AM

Leave TPS enrich at .10 for now

Look at the FO output on your Pro on the sensor monitor page, thats what Bob was talking about.

Yes, leave the KPa points stock and leave the tables at 0.

Turn afterstart to 0 (basically I'm going to tell you to turn everything back to start)

Turn mainscale to 0 and start the car, if everything is connected correctly it should start just fine.

That and did your disconnect the battery after disconnecting the O2 sensors to reset your fuel trims?

msassoon · 11-24-2006, 08:26 AM

No! I didn't reset the ECU. I will try this too. Also, the quick start guide says set TPS Enrich to .5, not .1, what affect will this have? I am replacing my FPR as I am not convinced that the FSE one is any good for my application.

DriveFast99 · 11-24-2006, 11:02 AM

Quote:

Originally Posted by DriveFast99

ok i need help. i h ave been having this issue and cant figure it out but it started ever since i did the install over the summer. The issue is the check engine light keeps coming on, but when i use my logger to see what is the issue it says no DTC's presnt, but my check engine light is on. I dont have PT tracking turned on and my o2 sensors are installed.

If i rest the ecu everything is fine for a few days then it happens again. Any idea of what could be causing this? i really think its the pro cuz it doesnt say i even have a code and has started ever since the install of the pro.

any idea on this bob?

Highboosted · 11-24-2006, 08:50 PM

EGR will cause a CEL without throwing a code that a logger can read... Does the CEL come on while your crusing down the highway?

11-23-2006, 06:07 AM	#1732 (permalink)
msassoon Forum Member Join Date: May 2004 Location: Berkshire, England Drives: GTO SC ATX Trader Rating: (1)	Re: ---===The Official MAFT-Pro Thread===--- What happens is, I press the accelerator (hard or soft makes no difference) and the AFR drops instantly, but it then richens up straight after. So, I guess I need to set TPS Decay and TPS Enrich. I am not using the charger, so there is no boost at the moment. The mainscale is +30 on standard injectors. I do have a number of mods for the intake and exhaust that would probably cause some extra fuel to be pulled, but I have to admit I am not sure why I have it that high. If I reduce it, I get leanness at idle. I am also not sure about the three load pages. It seems to indicate that they affect the amount of air on boost, but I have no boost. Should I reduce Hi and Mid Load Pt values to account for lack of boost? I would then increase them with the cahrger, but I want it sorted as standard first. For the mods, I have a Mongoose exhaust, 3SX DP, Ek2 Header on the exhaust side. Intake has a 3" intake from filter to TB and a VR4 plenum. The injectors are still 220CC and Fuel pressure is 43psi. __________________ 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

11-23-2006, 11:19 AM	#1733 (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===--- you'll just tune with the low table for now...leave the mid and high at 0. There still should be no reason you need to ADD 30% more fuel to a basically stock car....unless something is wrong with your connections or something.

11-23-2006, 10:28 PM	#1734 (permalink)
TurboBob Resident mad scientist Join Date: Jan 2003 Location: Near Detroit Drives: 86 GN 91 RT/TT Trader Rating: (17)	Re: ---===The Official MAFT-Pro Thread===--- There is something out of sorts with your setup. The stock ECU will figure out a way to idle even if the MAF signal is way out. But once you step into it the ECU will try to use the MAF signal. Do you have a logger? Look at MAF Hz, BARO, Air temp. What does FO read (on the Pro) at idle, MP? RPM? AFL? TPS? You should tune the mainscale to get it to drive decently, and then tune with the high/mid/low. With stock injectors, if you find that you are adjusting a lot (more than 15%) then look into connection or setup issues. Bob __________________ Need a datalogger? Check out the Scanmaster 3 PM me about ECU mods for 8000+ RPM rev limits !!!!!!!! Stock = 7300 RPM Stage 1 = 8060 RPM Stage 2 = 8200 RPM Stage 3 = 8400 RPM Stage 4 = 8800 RPM (By request only) 1991 Stealth RT/TT, Grooms Shortblock, 13G's. My Stealth is for sale, 65000 miles, runs perfectly. $6,500 (a bargain)

11-24-2006, 01:48 AM	#1735 (permalink)
msassoon Forum Member Join Date: May 2004 Location: Berkshire, England Drives: GTO SC ATX Trader Rating: (1)	Re: ---===The Official MAFT-Pro Thread===--- Ok, I will look into this. I am running speed density by the way if there was any doubt. It just seems like the tune is going lean expecting boost where there is none. I may be wrong. I will run the datalogger (TMO) and see what is happening. I just had the ECU rebuilt, and that is running fine, but I agree that 30% is very high.

11-24-2006, 02:10 AM	#1736 (permalink)
msassoon Forum Member Join Date: May 2004 Location: Berkshire, England Drives: GTO SC ATX Trader Rating: (1)	Re: ---===The Official MAFT-Pro Thread===--- Just to clarify, I set the mid and high settings to 0% across the board? Not the kPA activation points? Also, what are TPS enrich, TPS Decay and MAP Enrich measured in? % or some other value? I increased my TPS enrich to 1.3 today and it had no effect.

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11-24-2006, 08:21 AM	#1737 (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===--- Leave TPS enrich at .10 for now Look at the FO output on your Pro on the sensor monitor page, thats what Bob was talking about. Yes, leave the KPa points stock and leave the tables at 0. Turn afterstart to 0 (basically I'm going to tell you to turn everything back to start) Turn mainscale to 0 and start the car, if everything is connected correctly it should start just fine. That and did your disconnect the battery after disconnecting the O2 sensors to reset your fuel trims?

11-24-2006, 08:26 AM	#1738 (permalink)
msassoon Forum Member Join Date: May 2004 Location: Berkshire, England Drives: GTO SC ATX Trader Rating: (1)	Re: ---===The Official MAFT-Pro Thread===--- No! I didn't reset the ECU. I will try this too. Also, the quick start guide says set TPS Enrich to .5, not .1, what affect will this have? I am replacing my FPR as I am not convinced that the FSE one is any good for my application.

11-24-2006, 08:50 PM	#1740 (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===--- EGR will cause a CEL without throwing a code that a logger can read... Does the CEL come on while your crusing down the highway?

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