Tripminder mpg problems in 92 ranger

[Joeschmo90]

So i read the article on here about installing a tripminder in a ranger and decided to do it.

It's a 92 ford ranger reg cab, long bed, 3.0L v6 and a4ld auto trans.

Got it working somewhat the clock and trip odometer part work great.
The econ (mpg guage) is way off, idling in park it says 0 mpg then as i'm driving the numbers will keep going up and up as i accelerate even if i floor it. i was going 45mph steady and it said I was getting 150 or so mpg (yeah i wish).

In most cars that have a mpg gauge stock when idling it'll say something like 40+ mpg and then as the person accelerates the mpg gauge goes down until they'll cruising at a steady speed

so whats going on here? is my tripminder broken? it seems its reading the signal reversed or something. what could i do to fix this?

I wired everything correctly as the article told me. the vss signal is hooked to pin 3 (a little gray with black stripe wire) and the fuel flow wire goes to pin 34 (which i had to add a pin for)

 

[Joeschmo90]

I also did some probing with my voltmeter and saw that pin 6 on the tripminder which is for the fuel flow signal has 12 volts when its not even hooked up to pin 34. is that right or is this tripminder busted?

and apparently its been calculating my mpg based on the vss signal not the fuel flow signal

 

[Joeschmo90]

Bump. anybody?

 

[Joeschmo90]

Bump. no one knows how to fix this or whats wrong? i got the idea from this website but no one can help with it?

 

[Spott]

Sounds like it's getting the wrong signals. Maybe you're numbering your pins differently than the author of the article. Obviously the Power and Ground are correct, and if your odometer is accurate, then the VSS is correct, too.

Make sure the wires for VSS and fuel flow aren't accidentally touching, and that the pins inside the connector aren't bent.

Aside from that, well....If you want to drive out to Idaho, I've got a nice lil electronics lab, we could get out the oscilloscope and the signal generator and the logic probe, and really diagnose the problem.

Spott

 

[edhondasm]

Sorry I'm new here....

.. but this seems the most relevant place to ask. I think I have the same issue. Followed the procedure. Made sure my hole for PIN 34 actually is 34. My Tripminder (while driving) keeps rising in MPG until stop. (then slowly comes down to 0) Also I would like to note the Odometer (VSS) seems accurate and fine. Gallons/Liters used, stay at 0. Time for the voltmeter! My Pin 34 (DOL) seems to be giving out 5V engine off, ignition on (engine off, key off reads 0v. Also accessory pos. reads 0v ) Engine on reads around 11.5V at idle, and drops to as low as 5.5V when the throttle is depressed (seems linear all the way through throttle depression) Just as I'm doing this I'm noticing when I turn off the engine (ignition on) signal voltage slowly dropping down back to just as my incredibly high MPG numbers did...

Shouldn't this be a mili-volt signal or something less than 1V? I also find it interesting the voltage is still there after the engine is off, ever slowly dropping back down. I feel like I'm doing something really stupid here, just don't know much of anything about this data output line. Any ideas or solutions (seems like this happens a lot but not too many people coming back to share their magic) would be greatly appreciated. Happy trails.

 

[edhondasm]

edit from earlier..

Culprit was a loose connection at the tripminder display end. The plastic pins inside the harness clip were busted. A quick push up on the connections revealed the DOL line (pin 6) was loose. (doh!) Just a tip if you're reading voltage (15-5v) fluctuations on the DOL (pin 34) line but nothing normal on the display, check the connections inside that clip... may just save you a couple hours of headache.

 

[ronclark]

Were did you manage to find a tripminder?

So i read the article on here about installing a tripminder in a ranger and decided to do it.

It's a 92 ford ranger reg cab, long bed, 3.0L v6 and a4ld auto trans.

Got it working somewhat the clock and trip odometer part work great.
The econ (mpg guage) is way off, idling in park it says 0 mpg then as i'm driving the numbers will keep going up and up as i accelerate even if i floor it. i was going 45mph steady and it said I was getting 150 or so mpg (yeah i wish).

In most cars that have a mpg gauge stock when idling it'll say something like 40+ mpg and then as the person accelerates the mpg gauge goes down until they'll cruising at a steady speed

so whats going on here? is my tripminder broken? it seems its reading the signal reversed or something. what could i do to fix this?

I wired everything correctly as the article told me. the vss signal is hooked to pin 3 (a little gray with black stripe wire) and the fuel flow wire goes to pin 34 (which i had to add a pin for)

 

[JimRummy]

Culprit was a loose connection at the tripminder display end. The plastic pins inside the harness clip were busted. A quick push up on the connections revealed the DOL line (pin 6) was loose. (doh!) Just a tip if you're reading voltage (15-5v) fluctuations on the DOL (pin 34) line but nothing normal on the display, check the connections inside that clip... may just save you a couple hours of headache.

Sweet deal Ed, sounds like you'll have all the trouble shooting done before I even get ready to do mine.

 

[edhondasm]

"where did I find my tripminder"

I found a couple for me and some friends at a local junkyard here in North Hollywood, So Cal. I'm not real good at differentiating models all lined up in the jy but I did notice a pattern after finding 2 making it real easy to scan the whole place quickly. All the ones I found them in basicly looked like the original men in black car ( http://i141.photobucket.com/albums/r71/Steam_McQueen/P9/P10/ford025.jpg ) with that square mesh grill with the ford logo center left in the grill. Most of those either had the close-resembling clock, or the "nice" models with the tripminder. I think I found 4 of these over 2 Jy's in the afternoon with my buddies just on this tactic alone (scanning the isles for that grill-type). Happy hunting!