'89 300-6 running rough
FTE Legend
Joined: Nov 2015
Posts: 30,966
Likes: 4,130
From: Angier, NC
Last I recall reading, the fuel pumps don't come on until the starter cranks. You can move the hot wire from the starter side to the battery side to diagnose the pumps. But what I remember is the system doesn't get power until the starter cranks, then after the engine fires and the starter is engaged power comes through the oil sender circuit.
That wire you said you can send power thru is the one that sends power to the pump(s) when cranking and why you can do that for testing.
Dave ----
Logistics Pro
Joined: Dec 2003
Posts: 3,782
Likes: 876
From: Foothills of NC
You swapped injector locations, put the intake back together, started it up, and it ran the same, miss on #6? You have 155lb compression, spark, injector impulse, and should be fuel squirting, and a new ECM. That doesn't make sense.
Can you post a video of it running and how the exhaust sounds?
Can you post a video of it running and how the exhaust sounds?
Logistics Pro
Joined: Dec 2003
Posts: 3,782
Likes: 876
From: Foothills of NC
With 155lb of compression, I wouldn't think stuck or leaky valve. I might would consider a flattened cam lobe. The valve may open enough to show compression, but not enough to run well.
Was there ever a vacuum gauge used to check strong, steady, vacuum at idle?
Was there ever a vacuum gauge used to check strong, steady, vacuum at idle?
Thread Starter
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Tuned
Joined: Oct 2001
Posts: 483
Likes: 6
From: Pelzer, SC
No, I have not done a vacuum check, good idea.
Not yet had the chance to pull valve cover and inspect valves.
I did do the test when you put a piece of paper to the tail pipe while the engine is running.
There was no hint of the paper being sucked inward, just steady outward.
Not yet had the chance to pull valve cover and inspect valves.
I did do the test when you put a piece of paper to the tail pipe while the engine is running.
There was no hint of the paper being sucked inward, just steady outward.
Thread Starter
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Tuned
Joined: Oct 2001
Posts: 483
Likes: 6
From: Pelzer, SC
Hello All,
First off thanks for all your help.
I am getting back to working on this problem again, finally. Took off work today since its a purdy day outside.
We been working 6 days week since the holidaze.
First off thanks for all your help.
I am getting back to working on this problem again, finally. Took off work today since its a purdy day outside.
We been working 6 days week since the holidaze.
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