Engine stumble-Driving me up the wall.
#1
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Engine stumble-Driving me up the wall.
I happened to notice tonight with the predator , that this stumble I have had in my motor for a while, happens just about in a perfect cycle. Like every 20 seconds it's like a very light brake tap and then it goes back to normal. I was watching timing with cruise set at 45(where it is most noticible) the timing sits between 38-41 deg. and all of a sudden the timing falls to 15-18 deg. just for a split second and goes back to 38-41. it is like clockwork.
I have changed plugs, cleaned air filter, top end cleaner, fuel filter, checked for a vac. leak using brake cleaner, used high octane, checked fuel pre. regulator, checked electrical connecters, Anybody have any suggestions?
I have changed plugs, cleaned air filter, top end cleaner, fuel filter, checked for a vac. leak using brake cleaner, used high octane, checked fuel pre. regulator, checked electrical connecters, Anybody have any suggestions?
#2
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i just got a custom tune from johan at diablosport, i never noticed it before the tune, but if i am easy on the throttle, my truck almost acts like it stumbles before the 1-2 shift. the tune i got has been great so far but i never noticed this before. wot it goes no stumble so i wonder if it could be the same prob.
i have no idea of what it could be. hopefully someone can chime in and help us out. besides saying get rid of it.
i have no idea of what it could be. hopefully someone can chime in and help us out. besides saying get rid of it.
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I've had driveability complaints in the past that sound similar to yours that turned out to be the cycling of the A/C compressor. You might try your your 45 mph cruise with the A/C off and see if it's that.
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oh yea, the a/c is the only thing that i can think of that might cause that. then again, i am no electrical expert so i am just guessing. was your a/c on? did the compressor kick on maybe?
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Originally Posted by M.Roberts
I happened to notice tonight with the predator , that this stumble I have had in my motor for a while, happens just about in a perfect cycle. Like every 20 seconds it's like a very light brake tap and then it goes back to normal. I was watching timing with cruise set at 45(where it is most noticible) the timing sits between 38-41 deg. and all of a sudden the timing falls to 15-18 deg. just for a split second and goes back to 38-41. it is like clockwork.
I have changed plugs, cleaned air filter, top end cleaner, fuel filter, checked for a vac. leak using brake cleaner, used high octane, checked fuel pre. regulator, checked electrical connecters, Anybody have any suggestions?
I have changed plugs, cleaned air filter, top end cleaner, fuel filter, checked for a vac. leak using brake cleaner, used high octane, checked fuel pre. regulator, checked electrical connecters, Anybody have any suggestions?
#7
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I ran it with the a/c on so I'll try no a/c today and try and check out plug wires too. I've got a tune from Johan too and have tried with or without the tune same result.
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#8
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I forund out the same thing last year. The Predator was good for something. Here is my thread about it.
https://ls1tech.com/forums/showthrea...ighlight=A%2FC
https://ls1tech.com/forums/showthrea...ighlight=A%2FC
#9
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Pull your spark plug wires off and put an ohm meter on each one. They all should be a with in few ohms of one another. If one is more than about 80 ohms higher than the others than it is bad. There is are normally about 2-5 ohms difference between them. Mine was doing what you described and I had a bad plug wire.
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Checked my plug wires came to anywhere between .41 to .44 kohms. What are they supposed to read? Have not gotten a chance to run the truck much today big I did notice some difference with the A/c off but I have not even drove it far enough to warm the engine up so I can't say for sure. Very interesting about the A/c timing deal. I going to have to check that out. Maybe I am just having normal stuff happening, but I bet mods just amplify the problem.