Want to custom tune my MGM myself...

R

RobH

New member
We have a 2006 Mercury Grand Marquis with the Handling and Performance Package. It replaced our totaled 1995 Buick Roadmaster with the police car engine and suspension.

I don't like the way our MGM drivetrain computer is programmed to upshift into 3rd and 4th and lockup the torque converter below 1500 RPM under partial throttle.

I want to modify the computer program for revised shift points and torque converter lockup speeds. I'm not interested in changing engine spark/fuel/octane tuning parameters.

I had the capability to change things myself with our Roadmaster and our 1995 Chevy Caprice ex highway patrol car. They were OBDI cars. I bought a program from Tuner Cat which allowed me to offload the drivetrain program via a serial cable from the OBDI connecter to my laptop and save it off in a file. I then made a copy of the file, edited the shift and torque converter tables, loaded the revised file into the car, and repeated until I had them the way I wanted them.

I also have 28 inch tall tires on my MGM instead of the original 26.6 inch tall tires. I've been living with the 5% speedometer/odometer error, but would like to correct that.

I know that I can pay someone to do a tune with several revisions for me, but it would mean several back and forths to get the tranny working the way I want it to.

Does anyone sell programs or hardware that will allow me to do my own adjustments of the tire size, and transmission shift points and torque converter lockup speeds?

Thank you in advance for any help you can provide.
 
SCT Pro Racer software and an SCT tuner would let you accomplish this. About a grand to get going. MartyO can you sell him this?
 
JoeBoomz said:
SCT Pro Racer software and an SCT tuner would let you accomplish this. About a grand to get going. MartyO can you sell him this?
Click to expand...

You pretty much summed it up!

To the OP, what are you hoping to accomplish by doing it yourself at probably twice the cost of having a tuner shop do it for you?
 
martyo said:
...To the OP, what are you hoping to accomplish by doing it yourself at probably twice the cost of having a tuner shop do it for you?
Click to expand...

Getting it done just the way I want it in a shorter number of elapsed days. :)

My Tuner Cat software, which I used on both of our 1995 GM OBDI cars, cost about $200.

Back when our car was new, I looked into it, and couldn't handle the idea of paying someone twice as much for doing something for me which I could do myself. We've since moved, and I'm now driving more hills where the transmission is wanting to lock up at less than 1500 RPM then unlock, then lock again if I back off the throttle slightly. I put my ScanGuage on it and am realizing what manifold pressures I am running at those low RPM's. Ford has it programmed for max miles per gallon. I'm more interested in max miles per engine. It only has 61 K miles and I want at least another 70-100 K out of it. I had 210 K on the 1995 Caprice when I sold it and never had the manifold or heads off of it. The 1995 Roadmaster had 145 K miles on it when it was totaled in late 2006.

My other car is a Jeep with five speed manual. I have owned more manuals than automatics in my life. I don't like the computer deciding to shift gears when it has no idea what I am going to be doing in the next 50 yards.

What is your proposal? Feel free to PM or email me.
 
Last edited:
RF Overlord said:
That's a no-brainer. These motors are good for WAY more than that...250k is common and 400k is not unusual.
Click to expand...

I'm talking about 70-100 thousand more miles for the car itself. I drive it easy, but I've had four expensive maintenance items. Throttle position sensor went out just after the 36K mile warranty, then the automatic HVAC controller, then the driver side SRS, then the passenger side SRS.

These things were no problem in the 1995 Buick Roadmaster at 145,000 miles and eleven years when it was totaled and the 1995 Chevy Caprice at 210,000 miles and fourteen years when I sold it.

I wonder if the computer is designed to throw expensive trouble codes at random times. Most cars are not kept that long, so one owner may not know what a previous owner had to pay for. I was a systems analyst/programmer for a large insurance company, so I know it could be done. And troubles could be programmed to happen to only 1% of the cars based on the production sequence in the VIN.

I thought the throttle position sensor would be a thirty dollar potentiometer with a half hour labor to replace it. Lincoln told me the throttle position sensor required replacement of the entire throttle body. When they replaced it, I took the one they took out to my mechanic friend and we pulled the two fasteners for the position sensor and they both broke as though they were designed to do so. If a replacement sensor were available, it would have required drilling out the failed fasteners, and then tapping the holes for new fasteners. It looks like Ford is deliberately designing things to be expensive to fix.

I don't know when the next expensive maintenance is coming along. My 2008 Jeep Patriot with manual transmission has 81,000 miles with nothing but fluids, filters, and spark plugs. My wife is no longer driving due to medical issues, so I will probably peddle the GM and buy a mini van if/when she needs a wheelchair.

This is the only Ford product I have ever owned. I bought the car so that she would have a safe large car and expected at least 100,000 miles with no maintenance expense other than fluids and filters.

Consumer Reports gave the MGM good scores on reliability. Except for 2006 and later. Oh well. Live and learn. Except for a VW bug, a Datsun 510, and an Isuzu Opel, I've had GM and Jeep vehicles since my first car forty-eight years ago. The GM I knew is gone; I don't like the Government Motors/China Motors replacement. I know that I'm an old fogey and that most consumers today are dazzled by the electronics and don't know what the so-called American manufacturers are selling.

OK. Rant off.
 
Last edited:
RobH said:
I'm talking about 70-100 thousand more miles for the car itself.
Click to expand...
That's what I thought you meant, so with the 61k you have now, I understood you to say you were looking to get somewhere north of 150k...as I said, that's a no brainer with that car...250k is easy.

RobH said:
My wife is no longer driving due to medical issues, so I will probably peddle the GM and buy a mini van if/when she needs a wheelchair.
Click to expand...
So if you're looking to sell it, why are you gonna do a custom tune?
 
RF Overlord said:
...So if you're looking to sell it, why are you gonna do a custom tune?
Click to expand...

Good question. I wasn't clear. I meant that when she needs a wheelchair I may sell it. And I may not. It depends on what happens. I was involved with the care of a great aunt, my father, and my mother towards the end of their lives. They each played out differently in terms of what transportation made sense.

So the future is unknown. I just got a new set of Michelin tires. On tuning, I may be spending money just to find myself putting the stock tune back in it to sell it. Or, I may drive it for another five plus years. Or it may get totaled like the Roadmaster. For what it is worth now, I might as well put as many miles as I can on it to get my investment back out of it in miles not put on my Jeep.

You pay your nickel and take your chances. Or, rather, these days you pay your dollar and take your chances. Happy Fourth to everyone. :flag:
 
PM or call MartyO
I imagine he can sell you the SCT handheld with a tune including torque convertor/shift point changes already to flash into your OBD port.
It will still allow you to make small shift point/firmness tweaks when you flash in, if you want to alter the provided tune after driving.
No need for the software program.
 
chief455 said:
PM or call MartyO
I imagine he can sell you the SCT handheld with a tune including torque convertor/shift point changes already to flash into your OBD port.
It will still allow you to make small shift point/firmness tweaks when you flash in, if you want to alter the provided tune after driving.
No need for the software program.
Click to expand...

Thanks Geoff!

I spoke to him a day or two ago.
 
RobH said:
My Tuner Cat software, which I used on both of our 1995 GM OBDI cars, cost about $200.
Click to expand...

Thanks for posting this, I am now looking into getting one of these tuners.

It appears that they don't make these for Fords? I'm having trouble finding them for non-GM vehicles?
 
Last edited:
martyo said:
Thanks Geoff!

I spoke to him a day or two ago.
Click to expand...
Cool! to the OP - Marty tweaked my shift/lock-up schedule to the point of being dreamy:P
massacre said:
Thanks for posting this, I am now looking into getting one of these tuners.

It appears that they don't make these for Fords? I'm having trouble finding them for non-GM vehicles?
Click to expand...
Having Tunercats OBD1 and Datamaster myself, it is great software - but not applicable to Ford. You will need another tuning solution.
 
You must log in or register to reply here.
Back
Top