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> No Fuel from Injectors, in crank mode
cary
post Jan 16 2006, 02:47 PM
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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.
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bd1308
post Jan 16 2006, 02:49 PM
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how bout swapping in another brain?

b
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cary
post Jan 16 2006, 03:02 PM
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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.
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cary
post Jan 16 2006, 03:03 PM
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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.
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DNHunt
post Jan 16 2006, 03:16 PM
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Explanation: Magic Smoke (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif)

Dave
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DNHunt
post Jan 16 2006, 03:20 PM
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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
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cary
post Jan 16 2006, 03:57 PM
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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.
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cary
post Jan 16 2006, 05:09 PM
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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.
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cary
post Jan 16 2006, 11:17 PM
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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 (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) . So the blocks wore off. So I assume when it spun it didn't open one or both sides.
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DNHunt
post Jan 17 2006, 07:39 AM
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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
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cary
post Jan 17 2006, 07:53 AM
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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.
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