Tripminder HIGH MPG

[Tiggie]

Who needs a hybrid when box wagons get over 180mpg? It was over 200 at one point. And I’m sure there is no decimal place.



Something is up. It’s got some preignition pinging going on... nothing terrible but it didn’t do it before today.

Under extended load, the tripminder reads correctly and runs fine, but under light throttle, I can cruise in the 50mpgs at 25mph. That’s not normal for this car.

Haven’t driven enough to see if it really is using that little fuel.




Sent from my iPhone using Tapatalk

[VicCrownVic]

My mom's '87 Country Squire had a tripminder. I seem to recall a running total calculated MPG and a instant MPG. I always liked to see what I could get the instant MPG up to, but don't recall what numbers I saw since that was about a 10-15 ago.

[Tiggie]

This car has never read over 80-90 on the instant. My average is 26ish, which is again not normal for this car. 18 would be average.

[DerekTheGreat]

I didn't think they read over 99? My dad's Mark VII would see numbers that high when coasting

[gadget73]

Open circuit between the fuel flow output on the ECM and the fuel flow input on the tripminder probably. When the tripminder isn't connected to the ECM it assumes almost no fuel burn so the MPG reads stupid high. I think its pin 34 on the ECM, goes to a blue/pink wire and eventually gets to the tripminder. 88 I think has it as a single pin round connector under the hood, hanging out near the wiper motor.

[Tiggie]

Readings were normal this afternoon.

I added the tripminder to this car and used scary vampire taps. That’s probably (hopefully) the problem. It came out of an 89 with that totally different wiring so I had to improvise.

[87gtVIC]

You found the eco mode button.

[Tiggie]

I was secretly hoping for the eco mode...

The 2012 Escape we have gets absurd mileage in a good way but mainly when off the accelerator. The fuel must get cut out off almost completely. Feels like you put the brakes on.

[RyPow]

The 2012 Escape we have gets absurd mileage in a good way but mainly when off the accelerator. The fuel must get cut out off almost completely. Feels like you put the brakes on.

Yup, deceleration fuel cutoff. Locks the torque converter and shuts off the fuel injectors. My 2012 F-150 does it all the time when coasting. I think there may be a yaw sensor having an influence on that mode too, such that it only happens on a downhill grade.

Sent from my SM-G900W8 using Tapatalk

[86VickyLX]

DFSO was added in the mid 90s to the crown vic. It literally shuts off all fuel until throttle input or a certain speed is reached. The ECM in vicky is from a 94 towncar. And DSFO is quite noticeable. If you're going down a long hill. You can literally just ride down the hill, with the injectors off, watching the temperature gauge just drop haha. It's a nice thing. The parameters are there in the A9P strategy, but I couldn't figure out how to get it to work.

[DerekTheGreat]

I know stickshift vehicles do this already. My '89 K1500 will cut off fuel when coasting as does our '92 F150 and my '94 Ranger. I tested it by cycling the key to off when coasting and there was no change or 'burp' within the drivetrain. Burp felt when flipping back to run though. Guess automatics just lean the mixture out then?