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Greetings,

The=20 following is my log from today. Suffice it to say that I'm pretty=20 disgusted. Based on the number on my secondary injectors, it does = appear=20 that they should be 50 lb/hr (525 cc/min) injectors. That should = be pretty=20 close to the stock 550's I would think, but they sure don't act like = it. =20 FWIW, they are MSD-2013 injectors, which are actually made by Rochester = as a=20 #17104487.

Rusty=20 (Maybe beer will help <g>)

8-17-03 = / 8 hours / =20 1336 total

Started the engine with new injectors, and = didn’t note=20 any improvement (grumble, grumble). =20 Here’s the troubleshooting sequence. All testing today was at low = power of=20 3000 rpm and below, and the backup controller never made any=20 difference.

Original condition: =20

Normal – rough =20 (using primaries)

Primary sw off- smooth (using = secondaries)

Secondary sw off- rough (using primaries) =

Swapped Primary and Secondary wires in the = engine=20 compartment:

Normal- rough=20 (using secondaries)

Primary sw off- rough (using = primaries)

Secondary sw off- smooth (using = secondaries)

The=20 above test is of course a contradiction, but I tend to believe the = individual=20 tests, not the one with both switches on.

Replaced Primary injector connectors (pri and = sec wires=20 still reversed):

Things do seem better, but it’s hard to = believe,=20 especially since the original plugs looked so much better than the ones = that I=20 have installed now. Still = not sure=20 this made a difference. = The engine=20 will now run reasonably well with either primary or secondary switch = off, but I=20 noticed that the mixture is way different for each. Maybe this has been part of = the problem=20 all along.

Put the primary and secondary wiring back to = normal, but=20 left the replacement primary plugs installed:

I=20 can still make either set of injectors run the engine alone, but turning = on the=20 secondaries, when at 12” MAP makes the mixture go crazy, and I = can’t seem to=20 find a mixture setting that is smooth. =20 I can’t see why turning the secondary injectors off and on = makes any=20 difference at this power setting, since they aren’t supposed to be = on=20 anyway. Tried manually = setting mode=20 7 at 15” again, and nothing changed (as it = shouldn’t).

Did=20 some testing with primary and secondary injectors. Cleared the settings in the = EC-2 to the=20 default MAP. Ran with = primaries=20 only, and the mixture was way rich. =20 Turned the mixture knob all the way down, and still too = rich. Used mode 1 to lower the = mixture until=20 it was about right with the mixture knob at the 9:00 position. =20 Switched to the secondaries only, and the mixture is way = lean. Had to turn the mixture knob = to the=20 3:00 position to get the = right=20 mixture. With either = primary or=20 secondary injectors adjusted for decent mixture, they will idle down to = about=20 1000 rpm fairly smoothly, so there’s no injector problems it would = seem. Once I figured out the = sequence, I could=20 quickly turn the mixture where it would need to go, and switch the=20 switches. Using this = method, I=20 could transition between primaries and secondaries. It=20 sure doesn’t seem like there should be 180 degrees of = mixture knob=20 difference between sets of injectors. =20 I’ll be double-checking the MSD injectors that I got for = the=20 secondaries. They were = supposed to=20 be 550’s I thought, so they should match my primaries. The MSD number on the = injectors is “8132=20 17104487”.

I=20 tried without success to make the engine run right with both sets of = injectors=20 enabled. Just not sure = what the=20 problem is. I = couldn’t seem to do=20 much good, other than correcting as needed with the mixture knob.

Part=20 of the problem now is that the air fuel gauge doesn’t seem to be = registering=20 correctly. I noticed this = the other=20 day also. Now that the = sensor is=20 pretty toasty, the meter reads two bars over the middle of the = gauge. Turning the mixture up, or = down makes a=20 noticeable change in the engine, but not on the gauge. This is partly what led me to = change the=20 injectors, and now I doubt there was anything wrong with them.

To=20 make matter even more confusing, at some point, I noticed that turning = off and=20 on the secondaries at very low power stopped making a difference in the=20 mixture. This is how you = would=20 expect it to work, but it sure isn’t how it was working a few = minutes=20 earlier!!!

I’m=20 just about ready to send the computer back to=20 Tracy for a checkout. Very disgusted. Not sure what else to = try.