Dave WM

I am considering this AEM Electronics 30-7113 AEM Electronics Infinity Series 3 ECUs | Summit Racing

old ad I know, you still got the black one? I am looking for a possible backup.

will be doing some more testing soon, hope its not the AFM. I suppose I could try some testing on that with a voltage supply and my analog meter to read the sweep.

more reading, seems like if I just ground the o2 sensor for more than 10 seconds (lean condtion) then it reverts back to open loop. That way I can make sure its not a CL problem or and O2 sensor. Seems like the ECU ignores both over lean or over rich conditions if they go on to long. I should be able to detect this by checking the green led (off all the time) after grounding out the 02. The idea is to determine if the rough running at 2k is associated with the loop status.

cgs, I will post up some video of the actual test run later. Any idea on why the running poorly takes place as soon as the green led becomes active? Perhaps as you say I should look elsewhere for the reason I have the poor running condition at 2k rpm constant speed after warm up (other that closed loop O2 that is). I will conduct some more test after I get some new plugs. That way I can read them as well to if indeed the mix is rich or lean. Suppose I could install my color tune plug as well to see what is going on. I suppose since it takes place after warm up the CHTS should be the 1st suspect, it seemed to have the correct value for the heat range, but I did not test it at the ECU pins so will do that also.

oh and it will run fine if I just goose it when the poo begins. Revs up fine.

ok so the green light comes and goes when doing the described test. It also runs like poo when just held there at a very high idle (and the green led is flashing on and off. I seemed to be lean as I could depress the flap on the afm and it would clean up, as if the CL was causing a lean run. The O2 sensor was showing over .5v when this was going on as well, as if the O2 sensor was telling it your rich when it was not. So my only guess is this is: this rough running at 2k plus no load is normal the O2 sensor is not correctly reporting the oxygen levels I have missed some thing in the wiring of the sensors. I checked the throttle position sensor (on at idle off above idle), the head temp sensor (340 ohm at about 170f right on the chart line). Forgot to check the air temp sensor, will do that (located in the AFM). Timing set at 20 BTDC (per FSM for turbo). The only other thing I can think of is maybe getting some new plugs in there just to make sure that is not an issue, its been idling a LOT on those plugs, maybe they are a bit fouled and not happy with a lean run.

roger that thanks, will do some testing, pretty sure I never looked at it unless it was idling. I suppose my warm up period where it gets to about 165f will be ok, If it does not work I will try a 185f T stat. I also have a new bosch O2 sensor I can try.

there is a green led, I see it come one with KO and goes out after start. I will need to get a turbo FSM and study it. All I have done so far is consult the wiring diagrams. Some where I recall reading that it will not go into CL until completely warmed up (both the engine and the O2 sensor which does NOT have a heater built it). Also IIRC something about the led comes on when the mix is rich, dont recall where I read it. Clearly FSM is next.

I have it working pretty well now. the idle up just uses the vacuum from the stock FICD solinoid (rather than operating a pull up servo, is directly access charge air and adds that to the intake manifold). I may end up scoping the duty cycle of the injectors just to see if there is any change with 12v on the pin 22. My next goal is to adapt the wire harness to the 6 pin connector of the stock 75 harness. My goal is to be able to wheel the run stand next to the car, plug in the harness from the run stand to the under dash harness, start the engine on the run stand from the key in the car. Then test to make sure all the normal indicators work (tach, oil, temp) I just want to make sure the rest of the body harness is not effected. The igntion will still use the + coil connection from the body harness, but the blue neg wire from the ign module inside the car will be disconnected, the ECU drivin transistor driver will take over that duty. I presume the tach is in the wire engine harness, hence the reason for leaving that installed and just disconnecting at the stock ign module. I had quite a journey getting the crank angle sensor issue worked out (intermittent cut off after running for a few minutes). I did check for exhaust gases in the rad again, all good. cooling seems to be fine as well, revs out nicely. Not sure how to check the ecu for closed loop operation. I did not notice the typical oscillation of voltage at the O2 sensor, but it did hover right around .5v the whole time.

as kirk would say, double dumb arse on me!

That napa looks like my OE alt.

looked it up on google P Pulse Stator connection for tachometer

When I purchased from a local store like autozone I have the check right out of the box. Can't hurt... The alt I have on my test stand has a label that say 14118, has the P connector Zhead do you have more info on that P connection is about? I am pretty sure my other backup alt had it as well, just did not connect to anything. I am using a mechanical VR on all my engines (the NA test stand, the Turbo test stand and my car). IIRC my car has an original looking hitachi, no "P" connector. Its failure mode as a shorted diode. I replaced the diode pack and its been good for years now. Frankly I trust it more than the reman stuff that looks nice but I had one fail on a trip not that long ago, so now only my test stands use reman, I will try to fix them myself for now on if I have a failure.

BTW, if you have a fuel injection system (correct for a 77 to be FI not carb) I would HIGHLY recommend you get the correct fuel filter, not that plastic thing in there.

been working away on the test stand. other than an intermittent spark (think its a wire harness issue with the CAS but still need to confrim that with some more testing) all going well. I tested the idle up servo for the AC control. Works by applying a vacuum to a small hose, this allows bypass air to increase thus upping the idle speed. Works great. Question, the FSM calls 12v to be applied when the FICD is active. This goes to Pin 22. I cant for the life of me figure out what its supposed to do. If the idle up servo is work to increase the bypass air, what could the ECU add? If the ECU is only responsible for fuel mix and ignition fire and time, I would assume it has to be adjusting one of those. Seems to me bypass aire by default would take care of fuel mix do to the AFM. So that leaves timing. Perhaps it adjust timing, but seems to me added RPM would automatically deal with timing. Anyway hope someone has found out what this is for. Driving me nutz...

finally got the turbo EFI hooked up, will work on a rad and an alternator so I can have longer test runs.

I try to be safe but sometimes just mess up. Lots of foreshadowing, Same as when I commented about the pikes peak cliffs. Anyway I got off easy and will try to do better in the future. Progress is slow on the turbo engine but steady. Got the AFM mounted to a perch and a good location for the Coil, Should be working on the wiring harness soon. This time of year is my busy season so fun tends to take a bit of a back seat.

all good now working on a "Safety FIRST" video will post soon. Pressure holding, injectors nozzles directly viewed for leakage. Next step will be on to the ECU hook up (coil, transistor to fire, IGN switch, sensors, etc...

in the 1st part of the series, there was a lot of foreshadowing in the discussion. I seem to have a penchant for that, as in the pikes peak video talking about not wanting to test the drop off the side of the mountain, then needing to nearly back off the side of the mountain as the engine dies.

The Jay Leno thing was exactly what came to mind, a little older than me (not much) and did something stupid as well. Life is really just a crap shoot, sooner or later you get bit, just have to hope it's not too terrible). I was kinda glad the camera was rolling so maybe someone else may see and learn to avoid my goof up.

just real lucking nor ignition took place. Never too old to learn I suppose.

My lesson learned is NEVER get near an open spark plug hole. Never know what may come out to bite, oh and always have GOOD eye protection, don't rely on reg glasses. I knew gas was going to come out, just did not anticipate the ferocity of the event as I was spinning the crank quite slowly.

Me clearing a flooded cylinder...

all done