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MS2; Rich into boost

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black cotton

10+ Year Contributor
68
5
Mar 2, 2009
Naugatuck, Connecticut
Brief History. I bought my MS2 sequential from Symtech, and when building my harness; un knowingly used Butt Connectors, and Also ran my battery power and ground under my MS Unit.

I obtained a "Idle Tune" from another member to get the vehicle started and made an appointment at a tune shop to be tuned. After a few glitches and a full day on the dyno, they (they dyno shop) told me I needed to rewire the entire harness, and relocate the battery power and grounds away from the MS Unit, and my issue of "mis-firing" under load (trying to build boost) would go away; And that the tune was good enough so that once I fixed these issues, I could put a few miles on the vehicle before returning to complete the tune.

Fast Forward. I just finally got around to rewiring the MS Harness, and relocating the route of my battery power and ground. I fired the vehicle up, let it reach operating temps, and took it for a spin. Same issue. So I decided to hook up my lap top and see if I could data log anything. Here is what I found.

My VE1 table range is 700rpm - 4400rpm (this explains my in ability to rev over 5100 rpm according to Tuner Studio.

On the opposite side of the map i noticed fuel load % was being used instead of Kpa. This range is 30-310. I have no understanding of this value in reference of/to vacuum vs boost.

Also note, I can get the vehicle to rev with no issues to roughly 4800-5k RPM as long as I keep TPS value under 15-20%. Once I apply any more load onto the motor, (try to bring the throttle position over 20%) and engine vac drops to 0, the vehicle will being to "misfire". However In my opinion its flooding out. EGTs will drop to 3-500*F, sending my AEM wideband to "---" and you can literally see gas coming out of the tail pipe. I feel my whole problem is tune related, in regards to flooding out entering into boost, which for my motor/turbo combo should be in that 38-4400rpm range.

Any insight would be great. Thank You.
 
Any reason why when I attempt to load the forum tells me it's an invalid file?
 
This is Matts tune, but I don't want to point fingers or place blame until I myself understand what is going on. In fairness to Matt, I have not contacted him since performing his suggested repairs. Mainly because I expected to be able to drive it like I was informed.
 
Probably going to have to sign up for a free account on mediafire.com and upload it there. Post the link to the files here.
 
From your logs I would say you can't rev because of how lean you are, its showing 18:1 AFR's. The Fuel load is actually your map value in Kpa's. And Your right, another reason(and is probably related to how lean you are) is that you have NO scaling after 4400 RPM's and your MSQ is not set up for dual table. Deff has some issues with that. What is your set up?
 
I know my afr's read 18-1 however my egt probe highly disagrees as it quickly drops from 1150* to 3-500* at wot.

My set up is a basic 2.0 bottom w/ all the goodies, p&p head, crane 16s on stock timing, w the rest of the head built to max spec w all the upgrades. JMF sheet aluminum intake, mustang 75mm throttle body, JMF long tube equal length divided manifold, twin scroll gt35r, 1 bar springs in both gates, 3" turbo back straight pipe, hahn large core fmic, 2.5" IC piping. Wally in tank, 6an feed and return, custom rail, FIC 1000s.
 
I know my afr's read 18-1 however my egt probe highly disagrees as it quickly drops from 1150* to 3-500* at wot.

My set up is a basic 2.0 bottom w/ all the goodies, p&p head, crane 16s on stock timing, w the rest of the head built to max spec w all the upgrades. JMF sheet aluminum intake, mustang 75mm throttle body, JMF long tube equal length divided manifold, twin scroll gt35r, 1 bar springs in both gates, 3" turbo back straight pipe, hahn large core fmic, 2.5" IC piping. Wally in tank, 6an feed and return, custom rail, FIC 1000s.

Thats odd for your EGT's to drop that low, is your AFR gauge calibrated? And where is your prob at? 3-500* seems VERY low to me for you to be at WOT.
 
Not exactly sure how to go about or even that I had to calibrate my wideband. I am using a AEM Uego.

EGT probe is in cylinder #1 runner roughly 2-3" away from head; and trust me I was in shock, until I checked my oil (which smells like gas), and my exhaust literally spews richness.

I have been told that AEM's have the tendency to read super lean when the motor is actually super rich... IDK what other experiences other people have with that statement however. Im just struggling to argue a temp gauge vs an electronic device. I can determain which is right however by taking my emissions analyzer and stuffing it in the tail pipe and reading what that machines wideband reading is; and believe by the odds 2 to 3.

As for posting my tune and datalog for all to see; if someone can inbox me how to do it, I will.
 
Not exactly sure how to go about or even that I had to calibrate my wideband. I am using a AEM Uego.

EGT probe is in cylinder #1 runner roughly 2-3" away from head; and trust me I was in shock, until I checked my oil (which smells like gas), and my exhaust literally spews richness.

I have been told that AEM's have the tendency to read super lean when the motor is actually super rich... IDK what other experiences other people have with that statement however. Im just struggling to argue a temp gauge vs an electronic device. I can determain which is right however by taking my emissions analyzer and stuffing it in the tail pipe and reading what that machines wideband reading is; and believe by the odds 2 to 3.

As for posting my tune and datalog for all to see; if someone can inbox me how to do it, I will.

I can completely understand that, have you tried taking some fuel out up top to see? If not when I get home today I can pull some fuel and send you a map, but it will be a while.
 
Well what i dont get, is that I extended a map to 7250 leaving kpa at 310 and i remained w the same issue. If you wouldn't mind sending me a trial map to test I would genuinely appreciate it.
 
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