4 cylinder oem mileage computers

[getnpsi]

How many obd-I vehicle models are out there with oem mileage/trip computers? I read that there is one pontiac, can anyone remember who else made them?

[meemooer]

my 88 beretta had one. It had a vertical gauge that was a digital graph of Mpg

[getnpsi]

The original reason of my post was to ask what cars have them because I only know what ive owned. However not long after I made the post, i took a look on ebay for "trip computer" and mpg computer. Slim pickins for non-v6/I6/v8 applications. However a few of them looked like they were DIN sized which totally kicks butt in the interior presentation department.

Most of the sellers are wreckers and resell companies so its probably just a fraction of what they have. I have plenty of yards out where i live so its easier to get one myself from the "pickapart," not to mention I get to see how they are hooked up and I can swipe the harness/plugs they have that a online seller wont provide.

My only other question I have is if i hate all the old car options but really like one that is from an obd-II vehicle, does the other computer get its info from the obd-II ecu or from the sensors themselves?

[nowhhs]

I don't know about the obd2 computers, but a lot of the earlier ones have different protocols depending on the manufacturer. I tried to install a computer out of a chrysler lebaron into my Civic, both 4 cylinders, and it didn't work because of the different signal requirements. It would power up, self test ok, but wouldn't give any mpg info. I had the correct wiring schematic for it, so I know it was wired up right. I think, but don't know for sure, that it needed a processed signal for the fuel usage rather than just the injector tap. I finally wound up using one from a 6 cylinder Acura because it had the same signal requirements as what my Civic could provide. Good luck.

[getnpsi]

nowhhs, was there a lot of work doing conversion when there is a different of 6 cylinder and 4 cylinder? my question is because there are plenty of 8 cylinder applications that look to be din sized and would look pretty acceptable in my car which has double din.

[nowhhs]

The problem is that there is no way to compensate for the number of injectors or injector size. The Acura computer I'm using reads about 50% of actual mpg, 6 cyl. vs. 4 cyl. and 240cc injectors vs. 190cc injectors. So its useless as far as knowing the actual mpg. What it is good for is noting changes in mpg. On the other hand, it only cost me $15 and does what I need it to do. I calculate actual mpg when I fill the tank. That is going to be the problem no matter what computer you find. Unless it uses the same protocol, has the same size injectors, same fuel pressure, and the same number of cylinders, you're screwed. I doubt any OEM computer would be adjustable because from the manufacturers point of view, it doesn't need to be. You might consider making a nice faceplate for a mgpguino (sp?) and be done with it.