Assuming that diode is bad, and it seems to be on mine, it prevented the idle up function from operating at all as there was equal voltage on the VSV + and -. As a result the VSV would not trigger and send vacuum to the dash pot to increase the idle.
If your AC amp is triggering the VSV when...
Thanks for the heads up. I might just replace that and have a spare.
Do you know how I spec and buy that? I am an ME but have been designing EV's for a long time so have some idea what you mean but don't know enough to spec the diode.
Frank
Well luck struck out of the blue, my buddy had one in a parts rig, I installed it and it all works like it should. I set the AC idle up speed to 1k and the vents feel colder.
Interesting, though the part numbers are the same the connectors are different colors. The green connector is the...
So I replaced all of Mudhorn's AC parts that touch refrigerant last summer but never got the idle up to work. I had increased the idle to trigger the AC clutch and adjusted the RPM potentiometer to prevent any rapid cycling. I jumped back into this summer and what I found is that I have 12V on...
I ran the 3FE with an H55 too and had zero issues.
To the original poster, you might take your meter and Ohm out the resistors to the corresponding pin. Note the resistance, even post up here. Then, plug in the ECU and measure the voltage at those pins. I am 99% sure that those are pull up...
Congrats at passing smog! I know the feeling. I took care of this issue forever and gained a more powerful truck in the process... Mudhorn Passed Smog with 3FE manifolds! - https://forum.ih8mud.com/threads/mudhorn-passed-smog-with-3fe-manifolds.1286431/
Something to consider.
Frank
Friends today is a glorious day. It is such because Mudhorn didn't just crush a smog test but did so with 3FE manifolds here in good old SoCal!
There a few good threads about adding 3FE manifolds to the 2F so I won't go into that. I machined down the 3FE manifolds where I could with my...
You don't shorten the block to produce more power at the expense of crank angle. That's just shooting yourself in the engineering foot. Proper boring and destroking would maintain proper crank angle and maybe shorten the block. Just as an example, the 3FE's pistons protrude unusually far at...
So I installed 3FE manifolds on my 2F. I also have the DUI distributor. I had a 3FE / H55 swapped 60 for many, many years. I can say that with this combination, the 2F / H55 feels very much like the 3FE / H55. The 2F has gained 1k of useful RPM. That's key for around town drivability...
Make sure the blower motor isn't rotated. It can be mis-clocked on install which will really reduce air flow through the vents. It's easy to check, just loosen the 3 nuts, rotate it 120 degrees and test. The strongest vent flow is the right position.
Frank
Temp is what it is. Although inlet temps are likely to be higher at low air flow rates where it spends more time in the manifold. In fact, detonation, which increases with high inlet temps, is worse at low RPMs - the only place the engine can run with such restrictive intake/exhaust. Thus...
Warmer air helps with cold start emissions but otherwise it reduces the density of the air and promotes detonation and NOx production (higher combustion temps). The reason folks like cold air intakes (snorkels do this) is that denser air makes for a stronger explosion and so more power /...