Zed Head

It's a perfect bathroom library book. You can learn something in just a paragraph. Don't even want to think about mobile phone/super computers in the bathroom...

Post #37 here has the part # for the transistor - http://www.classiczcars.com/topic/56143-super-rich-plugs-fouled/?page=2 You can also read our past ramblings, insights, and conclusions about ECU problems. Might be entertaining.

I'll dig up the number. The connections from the transistor pins to the board are fairly fragile looking metal ribbons. Very easy to see, the two transistors are on the top edge of the assembly. ~Quarter-size. I could see one of the ribbons getting damaged if somebody poked around in there. You never know. Besides that, you'll want the part number for the ECU. There are several.

You might want to wait until you know which camshaft you'll be using before you buy lash pads. If you get a reground cam profile, the lash pads will be different than with a stock camshaft. Also, waiting until the head has been inspected is a good idea too since it's possible that it's warped or cracked or eroded internally. It might not be worth rebuilding. The basic process and steps, in order, is/are described in the "How to Rebuild" book that site linked to (which you really should have bought before you even started. It's very thorough). If you find the right shop/mechanic they'll know the details of lash pads and rocker arm wipe patterns and other details. If you get the wrong one they might try to guess their way through and they can make a mess of things. Somebody on another forum got a single bad/tight rocker arm and ruined his camshaft. When things are right they're very durable. When things are off, they can fail quickly.

Just for fun, you might take the ECU cover off and make sure the transistor wires are intact, and/or not shorted. The ECU location can get moist if a leak develops at the windshield. I actually have some part numbers for a replacement transistor and did replace both on a bad ECU. But probably for the wrong reasons, they tested okay afterward. It was probably something else. Your situation though, with three dead injectors, looks like maybe a single transistor or its wiring.

That looks like the replacement relay for the original JECS relay. Which is actually based on the Bosch system. It's actually two relays in one, EFI and fuel pump. Despite all of the pins it's a fairly simple relay. If you get the readings that you should at the ECU connector, don't worry about it. Many people "assume" and replace, it's hard to resist. If you get tricky, you can ground the injectors individually at the ECU connector, just like it would, to test the complete circuit of wires, power and injectors. I made some male pins to use in the connector from a flattened piece of solid core copper wire. Makes it easy to get an alligator clip connected to supply power and ground. Forgot to say - there's a procedure for testing the EFI relay, if you get odd numbers. In the FSM, Engine Fuel chapter, and probably in that EFI book too.

You can check for power at the injectors with the key On, with a meter or test light. I think that power is supplied in a set of two and four. But it's grounded through the ECU in sets of three. So you might have an issue with the ECU. If you have a meter, going through the tests in the EFI Guide is the way yo do things. It's what's happening at the eCU that really matters and most of the tests start there. The 1980 EFI guide (in the Downloads section) covers all years up to 1981. Use that one.

You were almost to a good conclusion. When you put the 3 rear connections on the 3 fronts, did the 3 front cylinders start working instead of the back 3? Or did the same cylinders work, just with different connections? If the cylinders that work follow the connections, then it's a connection problem. If they don't, it's a spark or mechanical problem. These engines will start and run with the firing order of the plug wires backward. They sound like they're running on 3 cylinders when you do that (by accident, of course). Finally, history of the engine helps. Did it ever run right, as far as you know? Edit - sorry for the ad. It came with the edit box.

This seems a bit presumptuous. You have the need.. Seems like this would be a place where some ingenuity and some LED bulbs could result in an improved system. Maybe even a light with a focusable lens, like the LED flashlights. The stock system really isn't a lot of help, especially n a metro area where the street lights cause sharp shadows.

BE-6 has a nice wiring diagram. Shows a red w/blue that powers the inspection lamp.

I've had numerous problems with my gauge lights. The sockets get screwed up and the contacts in the socket don't make good contact with the bulb. MSA's replacement bulbs were too big and rubbed on the inside of the housing. Some of the sockets have a ground wire attached to the socket itself, some of them ground through the edge of the mounting hole. Generally, the gauge lights are pain and require special attention to get working right, and installed without knocking something loose. My complaint might not help you but the point is it could be one of several different possible problems with each bulb. I had to go through each socket individually. And one of them still is intermittent.

p.s. most mechanics today will assume that the ECU has sensors for every component and use an IACV and/or ignition timing to control idle speed. The early EFI system is very primitive and hard to comprehend for today's code readers. The components mostly work independently with the engineers assuming that each individual component is adjusted to a certain specification. Very little adjusting to conditions, besides the coolant temperature sensor. They're very close to being electronic carburetors.

Dude. The above statement is wrong. Sorry. It's all described in the Factory Service Manual, in detail, with pictures.

p.s. only going in to detail because your first post suggested that you wanted understand how the EFI system worked. You're n the right place, there are many members out here who understand the EFI system in great depth. Your conclusions have potential, but are not right.

Sorry, and again, no offense, but until you turn that screw 1/2 turn and go out and show that it causes the engine to fall on its face again, you're just guessing and believing "mechanics" who probably don't really understand the engines. This - "When the car is cold and being enriched by the air regulator being open, it detects that and doesn't operate the same as it does when the car is hot and not under enrichment." and the "no doubt" cause a lot of doubt out here. Your conclusions and understanding are not right. The AAR is on its own circuit, the ECU has no idea what its doing. As I said, no offense intended. Thanks for sharing your observation. Go turn that screw 1/2 turn, you can do it by hand, and see what happens. The idle speed will increase slightly and that's all.

No offense, but it's probably just a coincidence. The proper way to tell if the "full enrichment" was happening would have been with a meter, at the ECU connector. From an experimental perspective, if you want to verify that the 1/2 turn of the screw was the cause, you would turn the screw back to where it was. The problem should return. The idle adjustment screw just controls an air passage that lets air past the throttle blade. It's the one with the big head and the spring underneath the head. Could be that your distributor breaker plate is sticking, and it broke free when you were testing. Just one possibility.

These old EFI systems tend to run lean once you get all the bugs worked out, ofent it's so bad that you'll get popping back through the intake. I have a method of richening the mixture and I can get a misfire/stumble if I have it set too lean. You could try it, it's pretty easy. http://atlanticz.ca/zclub/techtips/tempsensorpot/index.html The electronic ignition modules fail also but that problem tends to be more obvious than what you're describing. I'd try the the "fuel tweak" first. I have mine mounted in the cabin so I can tune it to the finest level. It makes a difference.

Nice. If you lower the car just a bit it will help the handling a lot. I've heard/read that the later cars sit a little high because there's certain height the 5 mph bumpers have to be at. Federal guidelines. Only mentioning 'cause you're going to work on the suspension.

You said you tried. Did it work? Do you have the FSM? You're kind of rambling around on what the problem is. There's a lot of "load" that happens before 5000 RPM. What kind of "stumbling" does it do? Is there any popping through the intake or is it just a spark problem? What does the tachometer needle do when it's stumbling? The pump noise might be from the filter before the pump, making it too difficult to pull fuel. Your fuel pressure is higher than spec. Not looking for buddies. Good luck.

What kind of electrical? Engine, lights, dash... They're different. And which garages have you tried? Probably best to stick to this sub-forum. Run a single thread.

What kind of electrical? Engine, lights, dash... They're different. And which garages have you tried?

You might check a lawnmower or small engine repair shop. The cables on those are two way actuators.

I think that they call them reservoirs. They work more as charging systems, air blows out but coolant gets sucked back in. You have to have the right radiator cap for them to work, with two valves, an in and an out. Dave WM, you might have a Canada car. Apparently they didn't get them. Cooling chapter...

Consider McMaster Carr also. https://www.mcmaster.com/#music-wire/=14yc2e0

Dang. Didn't realize how lucky I was. You might reconsider scavenging the wrecking yards. Some of the older bigger cars can have lengthy cables, with sheaths.