12 valve pop/ miss / shake... any ideas?

pete6030

pete6030

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Jan 27, 2011
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ok guys heres what i got 95 12v, 4k gsk, full cut dv's, rack plug, stock lines, 150 hp injectors, 23 degrees of timing and and 66/14/74 charger its all in a 03 f-250 with a 6 speed. i do not have a tach yet (trucks been drivable for only 2 weeks) but as close as i can tell it sounds like i have a miss from bout 800 rpm to 1500 rpm the engine and whole truck will shake in that range, at idle there is a slight shake but nothing hateful, if ive got my foot into it, it wont miss and in the high rpms it will flat out move, i doubled checked all my valve lash so does anybody have any ideas please let me know. thanks
 
I would check your timing to be positive its right and check fuel pressure too... Make sure your injectors aren't leaking anywhere too.

Oh and BTW this is James. If you need to you can call or text me 812-630-4079
 
ok ya ill double check my timing and fuel press, but if it was either of those why would it clean up at higher rpm i did a cut out test loosening the lines at the pump seems like #6 is doin the least but it still drops rpm
 
I would check for leaks around your injectors. I have had a few leaks that'll cause a miss. Mine would clear up after about 2k and be fine. Also check your intercooler boots for leaks.
 
timing is too low. pin the pump, pop the gear, turn it back a half inch on the dampner and retorque gear. itll be fixed.
 
injectors were pop tested before i put them in, its a new filter, just running straight out of the pump diesel, lenahan05 so i should add an additional 1/2 inch on the balancer or start over at stock and go back a half? wat confuses me the most is how good it runs once its opened up itll hit 47 psi and haul a** and from the smoke out put its getting plenty ou fuel
 
pete6030 said:
injectors were pop tested before i put them in, its a new filter, just running straight out of the pump diesel, lenahan05 so i should add an additional 1/2 inch on the balancer or start over at stock and go back a half? wat confuses me the most is how good it runs once its opened up itll hit 47 psi and haul a** and from the smoke out put its getting plenty ou fuel
Click to expand...

if i was you i would turn the pump over and pin it at stock timing. pop the gear. and then back the crank up about half inch. that should run good as long as your timing arm hasnt been bent to throw off your measurements.
 
talking about a timing kit. It's a dial indicator that goes into the #1 plunger. Depending on the pump, you set the pump cam lift at X amount and that will be at X amount of timing. Then torwue the gear at TDC at what ever Cam lift you have it set at. There are a few timing vs. cam lift charts floating around here...

There is a timing light kit you can buy that clamps to the injector line, but some opinions say they are not too accurate. Plus you would need a balancer with timing marks and make a timing tab to go by.
 
my opinion would be get the pump looked at if the timing is right. Could have a weak plunger. Also seen flywheels out of balance cause the same shake that may seem like a miss.
 
Saw this truck at Scheid this year on the dyno. It sounded to me like it was a weak injector or plunger.
 
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