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Runs now, only 5 cylinders? Has compression..


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Long story but in a nutshell:

 

'87 truck, Head rebuilt, bottom end MAY not last but giving a try, finally got spark and got it started.

 

Feels like its running on 5 cylinders. Did compression check:

 

125, 115, 120, 120, 120, 120

 

#1 spark plug looked like it might not have been igniting.

 

So it has compression, ALL ignition components are new, what can cause 1 cylinder not to fire-fuel injector not opening?

 

What should I test for with volt meter on fuel injector plug wires to see about this?

 

Anyone have a spark plug wire routing diagram to be 100% certain? I'm 99%..

 

What can cause tapping noise from engine, continue tapping for awhile when engine is turned off!?

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Replaced one spark plug that looked like wasn't firing, symptoms still the same.

 

With engine running, pulled plug wires to see difference. Pulling cyl #1 wire made no difference, all others did as should.

 

So #1 cylinder not igniting, but good plug & plug wire IS getting sent spark I got shocked by it.

That cylinder had 125psi compression.

This leads me to believe fuel injector not opening (I just swapped that wiring harness).

 

So, attempting to test fuel injector wire voltage now.

Does anyone have a pinout for main ECU connector wires & the #1 fuel injector, in case I have to jumper wire that?

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Off the top of my head I think the firing order is 1,5,3,6,2,4

 

 

It says on the intake manifold.

 

 

And I'd swap the inject with #2. See if the problem is on the #2 cylinder. If so, I'd probably get new injectors (yeah right) or soak them in injector cleaner, or more than likely I'd go to the boneyard and snag a couple more.

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And I'd swap the inject with #2. See if the problem is on the #2 cylinder. If so, I'd probably get new injectors (yeah right) or soak them in injector cleaner, or more than likely I'd go to the boneyard and snag a couple more.

 

Thanks man! Swapped with #2, yep its a bad fuel injector. There was even some corrosion on the electrical connection of that injector. I'll grab one from the boneyard now.

 

Just remember it like this....

 

15 is too young, 36 is too old, 24 is just right ;)

 

Jeff

 

Awesome, thank you sir I have a horrible memory but I remembered that when I was in the garage. :D

 

 

LETTING A CAR SIT FOR YEARS DOES MORE DAMAGE THAN YOU THINK!

For this one:

-bad fuel injector

-bad coil

-bad brakes

-exhaust leak

-lower compression in 1 cyl

 

Not the first car I've revived after sitting for years either.

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LETTING A CAR SIT FOR YEARS DOES MORE DAMAGE THAN YOU THINK!

For this one:

-bad fuel injector

-bad coil

-bad brakes

-exhaust leak

-lower compression in 1 cyl

 

Not the first car I've revived after sitting for years either.

 

Not only that but with my s-10 Blazer thats been sitting for only 4 or 5 years has been eating by rats, squirrels, or worse MONKEYS!! I can't believe an animal would eat metal or fiberglass.. No one is safe anymore..

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