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Old 02-22-2010, 12:24 PM   #1
asickber
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tune-up problem

My truck was due for a little work so I replaced the fuel lines/filters, plugs/wires, fixed an exhaust leak, and changed the oil. It runs much better when it's warmed up, but when first started it runs very rough. It seems to be getting enough gas, but the engine really shakes the truck. Also when I give it gas the lights get brighter and when I let off they get more dim. Is that normal?

Any advice on what to look at first?
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Old 02-22-2010, 12:28 PM   #2
jsbgump
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Re: tune-up problem

make sure you have the plug wires in the right firing order
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Old 02-22-2010, 01:21 PM   #3
asickber
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Re: tune-up problem

I didn't check the order to start with but I had been running the truck for years on the order it's on and it idled ok. When I replaced them I did them one at a time to not confuse any. I'll double check when I get home. I also gapped the plugs.
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Old 02-22-2010, 01:26 PM   #4
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Re: tune-up problem

points or hei dizzy? different plug gaps for the two//if points did you set dwell? have you checked for bad vaccume hoses?

lights getting brighter is normal
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Old 02-22-2010, 01:48 PM   #5
asickber
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Re: tune-up problem

Points. I didn't adjust the dwell and never have. Can I simply adjust it by trial and error and see if it runs better? I haven't checked the vacuum hoses so I'll look into that too.
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Old 02-22-2010, 01:55 PM   #6
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Re: tune-up problem

Can't run points and not adjust the dwell.
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Old 02-22-2010, 02:05 PM   #7
asickber
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Re: tune-up problem

When does the dwell need adjusted? I didn't change the points. Do you adjust it everytime you put new plugs in?
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Old 02-22-2010, 03:57 PM   #8
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Re: tune-up problem

every 5000 miles is a good interval for checking cleaning and adjusting points
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Old 02-22-2010, 06:29 PM   #9
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Re: tune-up problem

I have also purchased new plugs that were bad from the factory. Just a thought. Good Luck.
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Old 02-22-2010, 07:13 PM   #10
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Re: tune-up problem

If you set the point gap with a feeler gauge the dwell will be in limits.
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Old 02-22-2010, 09:12 PM   #11
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Re: tune-up problem

I would start with replacing the points and doing all the BS that goes along.
Actually, I'd start with an HEI swap.
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Old 02-22-2010, 09:17 PM   #12
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Re: tune-up problem

x2. any other effort or $ spent is a waste of time
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