2.0 FI Brains

[Jim Smolka]

I tested my FI brain using Tom's FI tester.
Pelican Rules...

The tester revealed that it was bad, so I replaced my FI brain this past weekend.

I noticed on Pelican FI parts web site, that there are different part #'s for the FI brain based on what year model.

Does anyone know the difference between the different part #'s???

Does it matter if you use a later or ealier model brain as long as it is for a 2.0???

Thanks...




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Smoke Daddy

[Joe Bob]

The early ones don't have the adjustment on the brain for lean/rich...

[Germain]

Can I go as far to say that (edited bacause I cant say that 2.0. FI is an oxymoron)

Wheres the ketchup?

[This message has been edited by Germain (edited 03-20-2000).]

[Dave at Pelican Parts]

No, you can't go that far. ;^) Now you have to edit your post and take those words out. Then eat them--try with ketchup, it always helps for me... ;^)

Anyway, there are some differences in the D-jet FI "brains" (ECUs). The early 1.7s (70 & at least some 71) don't have the idle mixture knob. They do have an "overrun cut-off" where the FI doesn't squirt fuel when you're coasting at over 2500 RPM. It was there as a fuel-saving and emission-reducing measure--but they disabled that later when they found out it actually *increased* emissions.

The 73 ECU is the same between the 1.7 and the 2.0. Same part number and everything. I believe that there are some relatively-subtle differences between the 72 and 73 ECU, but it wouldn't surprise me that much if a 72 1.7 ECU would work OK on a 73 2.0 FI setup.

In 74, they changed the ECU for the 2.0 (and replaced the D-jet 1.7 with the L-jet 1.8). They also changed the MPS and a couple of other bits. My guess is that the changes are still relatively minor, but they will affect the mixture. Again, I would guess that you can mix-and-match the ECUs and get something that works at least somewhat reasonably. It might require some tinkering, though.

In 75, they made more changes. The biggest one I can think of offhand is that they added a +12V wire for the thermo-time switch. The ECU had to supply that power, so that was a very distinct change. Odds are not as good that you can swap around pre- and post-75 ECUs and have everything work well. However, if you swap in an early TTS it ought to work out correctly. The MPS and head temp sensor were the same. The injectors were different part numbers, but I have yet to hear about any difference in spray pattern, flow rate, or electrics.

Hope this helps.

--DD