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Discussion Starter #1
Injectors are good, and have been pressure checked.
Valves adjusted
Compression test good, all 4 around 400

I still have a miss. Low power, poor fuel economy. If I keep the idle around 760 when i put it in gear it LOPES.

What else to check?
 

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this is obviously a IP issue.
 

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Ther was a guy,who listed his problems on a trip with his VE,and it turned out,there were some broken/worn parts in the Injector pump.....may be what's wrong with yours....
 

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Cheaper than a pump tho...get out the elbow grease and your clicker:) Just went thru this for a wristpin bushing.
 

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Discussion Starter #10
Seems like a compression check would've shown those two cylinders lower than the others....how did you confirm it was blown?
It ended up being 420,360,340,400...

The head has some weird raised areas in the piston area.
 

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Discussion Starter #12
No pics. Semi circular raised 'indentions' about the radius of the piston, but offset in the bore where it would be impossible to be a piston that runs into the valve seats on cyl 3. Same patter between 2/3.

Head guy has been doing it 25 years and said he has maybe seen it once before. No idea on cause.
 

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Isuzu reliability tester
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May still be an injector pump issue
 

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The return side is low pressure ! The only time you can have a miss is on high pressure side lift pump to I/P ,I/P to injector or air in the system,bad injector,or injuction pump . If your injector is leaking than yes you can have a miss only if it's on the pressure side !

Scott
 
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