We're still pulling our hair out. Took a perfectly running car. Pulled the engine to install a new muffler and straighten the front motor mount.

Now it won't start at times. Right now I have NO FUEL SPRAY from the injectors when we crank the ignition. It won't start like that.

Checked the valve adjustment, A-Ok.
Checked the ignition. All checked out, both HT & LT. We did have the ignition wire hooked to the (-) for a while.
But switching it back didn't help. Could that have burned up something I can't see ?
Fuel pressure perfect 29psi. Pumps 8 oz in 15 seconds.

Here's what I have now :

When you charge the ignition. One opposing pair of the injectors click. But a couple times. I got nothing. ZERO.
Then I unhook the harness to check the trigger points. I still get the click of the injectors with the harness unplugged. Is that right ?
So that leads me to test the harness to the ECU. All three (12, 21 & 22) test fine. Both continuity and signal. Still stumped. Tested the signal out of the trigger point connector. Fine on both sides.

Now I pull the injectors to test for spray. Nothing. I get a burst at the start. None during the cranking. Then a couple bursts when we turn the key off crank. That is screwed up. Pulled the plugs dry as a bone.

There has to be a simple answer. Its not that complex. But I'm missing something.

How come no spray at ignition crank ?

If your car has a bad injector resistor pack that would cause zero fuel at crank.Located over by the battery four wires out to one large plug. They are housed in a shiny aluminium housing.
CCLINNOGASNOGO

this is D-jet right?

b

Sorry, 73 1.7 D-Jet.

Craig,

Where is it located ? I don't see anything different than my 74 2.0 D-Jet.

scratch the resistor pack comment.

_Djet didnt have this.

but the "computer" (of sorts) is gettign power...so your not completly hosed.

are you getting a CONSTANT signal from the injector points?

did you check your injector grounds?

b

Here is what one looks like.
CCLINSHOWME

Okay never mind.
CCLINOKAY

QUOTE (boxstr @ Jan 15 2006, 10:12 PM)

Here is what one looks like. CCLINSHOWME

that resistor pack is not applicable to the D-jetronic injection system....

the positive power is actually supplied from the "ECU" and does not require a resistor pack like the L-jet does (which switches ground...)

b

Beats the s*** out of me.

Went back after dinner. Tested the MPS for vacuum. Failed the test. Sank to 10inches in 15 minutes. Bench tested the 2nd one, it failed too. Bench tested the 3rd. one. Held fine. All three, the coils tested ok.

Put in the good one and it started right up. Tested it about ten times. Started fine. We'll see in the am.

It doesn't give me much confidence. I like black & white. Not hazy grey.

Still has a waver at high RPM's. More than a flat spot. I have a rebuilt Cardone dizzy coming from NAPA. It may clear up all kinds of things.

Thanks for the encouragement.

Well its a new day. Went out this am to start it. Started, but only ran for 10 seconds then stopped. Not to start again. Now what ?
Same as yesterday. Something is shorted. Has to be.

I'm going to test and look at the CHT. That wire is down by the MPS. Your guys thoughts ?

Cary

A bad CHT will keep the car from starting but, I believe it's because it floods not from being lean. I imagine you have thought of this already but check all the connectors and grounds (especially grounds). If I remember there should be a constant ~ 12v which you should be able to measure available at the injectors and the FI switches the ground. It may be wothwhile testing the resistance in the harness also. The insulation on 30 year old wires gets awfully hard and can crack.

The fact that you were able to see some improvement after replacing the MPS makes me suspect connections on that side of the engine. In messing with my car I have found that the connectors at the injectors can become loose with thw D-jet style connectors. I've had to give the females on the harnessa gentle squeeze to close them a little and I've cleaned them to bright metal.

Dave

Dave, your right. Backwards. The CHT would give extra fuel. Tested the CHT 4050 ohms at the heated shop temp of 52. So its right on target.

We pulled the ground spade and cleaned all the connections. But I think its still a short somewhere around the MPS. But why only when the block is cold ?

If all the injectors click when you power the ignition. Why do they not get fuel ? If the grounds where bad. I would think that I wouldn't get a click at all.
But this am I didn't listen for the click. Hummmm.

I may pull the entire harness and wiggle test every wire in the harness.

maybe its time to get the harness rebuilt?


b

I'm thinking the same thing. I was just away at Jeff's sight.

I'm think I'm going to drop the engine again at take the harness out and test it. My Super In Law is at home still working on it. But he's getting a little worn out. Plus he wants to get finished on taking the engine out of the parts car. So we can flip it over and pull the suspension off. Thats a lot more fun than cussing at a car that won't talk back.

Wait a minute. I don't think i understood. Are you saying all of the injectors open? If so then there are a couple of possibilities. One is fuel delivery. What is the fuel pressure? Fuel may not be getting to the injectors so check the fuel pressure regulator with a gauge, fuel pump, fuel filter, sock in the fuel tank. Second possibility is electrical if fuel is getting to the injectors at the correct pressure.

These are peak and hold injectors so full current opens them and it is reduced to hold them open. Check the resistance in the harness. They may be openning and then not have enough current to hold them open so the pulsewidth is too short. The injectors maybe failing. Swap them to the other side and see if the problem follows them.

Good luck

Dave

Broken wire/connection at the injector connector(s)...You banged it on the sheet metal when you droped or replaced the engine...Breaks off right behind the metal contact in the connector...Hard to see but it sounds like you get it pretty close to contact and the start the engine, vibration breaks the contact again and you lose injector..

I will not admit to how I know this problem...

2-OH!

QUOTE (boxstr @ Jan 15 2006, 08:12 PM)

Here is what one looks like. CCLINSHOWME

what FI system did this come off of?

QUOTE (boxstr @ Jan 15 2006, 08:12 PM)

Here is what one looks like. CCLINSHOWME

could i see the topside?

The one on the left.

dlo, this is what I owe you...i'm working on it for you.

b

QUOTE (DNHunt @ Jan 16 2006, 10:56 AM)

Wait a minute. I don't think i understood. Are you saying all of the injectors open? No, none of the injectors are opening. If so then there are a couple of possibilities. One is fuel delivery. What is the fuel pressure? Fuel may not be getting to the injectors so check the fuel pressure regulator with a gauge, fuel pump, fuel filter, sock in the fuel tank. Right now I have a pressure gauge on the FI rail. 29lbs. Holds steady. I get 8oz of fuel in 15 seconds so that meets specs. Second possibility is electrical if fuel is getting to the injectors at the correct pressure. These are peak and hold injectors so full current opens them and it is reduced to hold them open. Check the resistance in the harness. They may be openning and then not have enough current to hold them open so the pulsewidth is too short. What signal should I be looking for ? I was getting a signal to each injector as the dizzy turns. Pulsewidth ? The injectors maybe failing. Swap them to the other side and see if the problem follows them. I did that earlier. Good luck Dave

Answers to the questions in quote.

how bout swapping in another brain?

b

Went home for lunch. Super In Law had the dizzy out adjusting the trigger points.
Put it back in. Started right up. Just like new.

Ran for a couple minutes. I turned it off. We laughed. We decided to take the dizzy cap off and put the rev limiter rotor back on. And adjust the timing.

Guess what, NO START.

I'm sure its the connector to the trigger points. It has to be. When I pull it off the females are twisted. Not squared up.
How do I get that connector apart ? Looks like I go in from the front to push the lock down and it should slide out. I can't get it to come out.

Dave, I don't understand the signal to the injectors. Seems the injectors get the click whither the trigger point harness is plugged in or not. It depends where the dizzy is it seems as to which pair click. ( Haven't double checked that ) How does that work ? Where is that signal coming from ?

With the harness hooked up ( connection ?able ). The #1 injector gives me a burst at the start. Nothing while your cranking. Then a burst when you turn the key off ?
Explain what I'm seeing if you can.

QUOTE (bd1308 @ Jan 16 2006, 01:49 PM)

how bout swapping in another brain? b

Tried that last night. Brain #2 didn't seem to help. But thats the problem I have Toooooo many replacement parts.

Explanation: Magic Smoke

Dave

I would imagine that the brain fires a priming pulse to all injectors on power up. I'm not sure about when you turn it off. Maybe now would be a good time to take a break and read Brad Ander's ste

Dave

I have to whole web site printed and in a three ring binder. My bible. I read it at night hoping I'll absorb all the knowledge. LOL.

But that brings up the question. Shouldn't all the injectors be getting the priming pulse ? I swear that only 2 opposing pairs prime at key on.

Update:

Super In Law pulled the trigger points from the 72 parts car we're tearing apart. Installed and adjusted with ohm meter. The SOB fired right up.

Its on the road right now for a kid tested road test. So its either the points. Which checked out fine. Or the other points made a new connection with the trigger point connector.

I'm going tinker with the other ( not working ) trigger points.

Okay it lives. Plus it has a bitch'n tune up. Did everything 10 times. Runs like a sewing machine.

So looking at the old set of trigger points. Looks like operator error. They where only 2 years old. But I didn't lube the dizzy shaft . So the blocks wore off. So I assume when it spun it didn't open one or both sides.

Good work you guys. I'm glad you have it up and going. How much driving do you guys get in MT this time of year?

Dave

Could have taken the top off yesterday. 35 degrees and a BIG blue sky. Both cars have an 80# sand bag in the trunk.

Not a drop of snow on the ground. A few piles in the parking corners.

Off to finishing tearing apart the parts car. We're down to the fire wall. The wiring harness in pile in the middle. Hopefully done this weekend.