---===The Official MAFT-Pro Thread===--- - Page 175 - 3000GT/Stealth International Message Center

msassoon · 11-25-2006, 11:15 AM

I need to reset the ECU, but stuff is getting weirder. When I decelerate, the AFR rises THEN drops. It is as though the TPS signal has been reversed. Any ideas? What have I connected the wrong way? Or settings I have set in reverse?

Barefoot · 11-25-2006, 11:46 AM

Hey bob, did you ever get a chance to look at my logs? Iam going to try to mess with the wiring today, but I don't understand why I only have bad Rs values at cruise, but not WOT/idle..

gearheadvr4 · 11-25-2006, 06:20 PM

Can someone point me in the right direction for setup with speed density on narrowband (ie stock) O2 sensors? I will be buying a wideband next week but need something in the mean time to get me running.

DriveFast99 · 11-26-2006, 02:57 PM

Quote:

Originally Posted by Highboosted

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?

yea it comes on after about a day or 2 of driving and then stays on till i reset the ecu again, but everytime i have ever noticed the cel coming on was while crusing on the highway.

Highboosted · 11-26-2006, 03:44 PM

Quote:

Originally Posted by msassoon

I need to reset the ECU, but stuff is getting weirder. When I decelerate, the AFR rises THEN drops. It is as though the TPS signal has been reversed. Any ideas? What have I connected the wrong way? Or settings I have set in reverse?

It's the VE table being too rich at 20 KPa and below according to Bob. I'm working on tuning it out, but so far I haven't been able to get rid of it...

Quote:

Originally Posted by DriveFast99

yea it comes on after about a day or 2 of driving and then stays on till i reset the ecu again, but everytime i have ever noticed the cel coming on was while crusing on the highway.

I bet money it's your EGR if you can't see the code on the logger, and it comes on during the cruising.

TurboBob · 11-26-2006, 04:17 PM

Quote:

Originally Posted by smurfmodsvr4

Can someone point me in the right direction for setup with speed density on narrowband (ie stock) O2 sensors? I will be buying a wideband next week but need something in the mean time to get me running.

With just a narrowband/stock O2 sensor setup, you can tune using the trims.

O2 trim generally indicated how you are tuned. The main trims (high, mid, low) adjust slowly depending on what's happening with the O2 trim. The O2 trim reacts immediately.

with version 4.40, the VE table is a little lean around 2800, so you will want to add some counts to the mid and high tunes from 2200 - 2800, about 8% if I remember correctly.

You should be able to get an acceptable tune using the narrowband and trims. Speed Density takes more tuning to get set up than an AFC, so be patient and you will do fine.

Whan you start, you need to verify all the sensors and signals. The Pro calculates airflow based on the sensor signals, and needs good data....

Bob

TurboBob · 11-26-2006, 04:19 PM

Quote:

Originally Posted by |4x4 NV|

Hey bob, did you ever get a chance to look at my logs? Iam going to try to mess with the wiring today, but I don't understand why I only have bad Rs values at cruise, but not WOT/idle..

I was waiting for you to post another logfile.

Bob

TurboBob · 11-26-2006, 04:21 PM

Quote:

Originally Posted by Highboosted

It's the VE table being too rich at 20 KPa and below according to Bob. I'm working on tuning it out, but so far I haven't been able to get rid of it...

I have been working on a little. I think there is something non-linear in how the Mitsu ECU is working. If I can work out the details, I can program the Pro to take care of it...

Bob

TurboBob · 11-26-2006, 04:31 PM

Quote:

Originally Posted by |4x4 NV|

Hey bob, did you ever get a chance to look at my logs? Iam going to try to mess with the wiring today, but I don't understand why I only have bad Rs values at cruise, but not WOT/idle..

I looked over session 39. I didn't see much wrong with Rs (Transient Response)

Your wideband value is really choppy. What kind is it and how is it connected?

Bob

Highboosted · 11-26-2006, 09:40 PM

Quote:

Originally Posted by TurboBob

I have been working on a little. I think there is something non-linear in how the Mitsu ECU is working. If I can work out the details, I can program the Pro to take care of it...

Bob

Something is fighting something because even with it leaned to the point of driving crappy it will peg 10:1 rich...I wonder if there's a way to add a "reverse TPS enrich" setting or clip the airflow output when backing out the throttle? Kinda like "airflow (output) can only read [this much] when TPS < .6" or "when TPS moving down"....hard to explain in words...

Even when completely stock we go a bit rich when shifting or lifting, so I think it's the ECU's fault, even though most people blamed the BPV or the long intake/intercooler piping.

11-25-2006, 11:15 AM	#1741 (permalink)
msassoon Forum Member Join Date: May 2004 Location: Berkshire, England Drives: GTO SC ATX Trader Rating: (1)	Re: ---===The Official MAFT-Pro Thread===--- I need to reset the ECU, but stuff is getting weirder. When I decelerate, the AFR rises THEN drops. It is as though the TPS signal has been reversed. Any ideas? What have I connected the wrong way? Or settings I have set in reverse? __________________ 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

11-25-2006, 11:46 AM	#1742 (permalink)
Barefoot Racing Join Date: Jan 2003 Location: Ga Tech Drives: 92R/T - converted ;) Trader Rating: (31)	Re: ---===The Official MAFT-Pro Thread===--- Hey bob, did you ever get a chance to look at my logs? Iam going to try to mess with the wiring today, but I don't understand why I only have bad Rs values at cruise, but not WOT/idle.. __________________ 92 Dodge Stealth R/T AWD/TT (TD05) converted ( 11.894 @ 120.56 - 18 psi -> Video )

11-25-2006, 06:20 PM	#1743 (permalink)
gearheadvr4 Forum Member Join Date: Apr 2006 Location: Fort Worth Drives: Pucking VR4 Trader Rating: (25)	Re: ---===The Official MAFT-Pro Thread===--- Can someone point me in the right direction for setup with speed density on narrowband (ie stock) O2 sensors? I will be buying a wideband next week but need something in the mean time to get me running. __________________ Permanently broke! But her soul will be reborn into another VR4 soon. 92 VR4- Rebuilt engine with forged crank, TD05 manifolds with MHI EVO 3 16g, 6 speed conversion done, Maximal Solid Mounts, front mount 3" w/custom intercooler and intake pipes, OFE Stage 3 Clutch (from Southbend Clutch), SS clutch line, SS brake lines, SS oil and coolant lines, borla exhaust, stillen downpipe, egr block-off plates, LC-1 Wideband, blitz dc2 turbo timer, hks ssbov, Maft Pro speed density, Blitz SBC i-D III boost controller w/ Power Meter, k&n filters & custom intake pipes, gutted cats, 18x9 blitz type 03 wheels wrapped in Nexen N3000 tires, intrax springs, adj. control arms, 97 frontend and side conversion, 99 center tail light piece (<--adds at least 20hp on the dyno )

LinkBacks (?) LinkBack to this Thread: http://www.3si.org/forum/f103/official-maft-pro-thread-290438/
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HOW TO INSTALL MAFTPRO ON A 91-99 3000GT VR4/91-96 STEALTH TT	This thread	Refback	04-13-2008 12:45 AM

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