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1998 GMC Sierra 1500 Base Reg Cab 117.5 WB

1998 GMC Sierra 1500
Trim Info:
Rear Wheel Drive, Reg Cab 6.5' Wideside
17 mpg city / 23 mpg hwy
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February 13, 2009, 4:20 pm

James B

Question: why does my truck run like crap

the ruck is running with less power than it should and is idling really low

March 1, 2009, 7:11 pm

Terry C

You did'nt say if your truck is fuel injected or carborated. Assuming it's F/I, go to your local automotive store and get a can of Seafoam fuel additive.Pull the brake booster vacum hose from the booster with engine at normal operating temperture,and idling. Pour about 1/3 of can in vacum hose, be sure to keep engine running while liquid is going in. Cut off engine and let it sit for about 30 to 45 minutes. Then crank (don't be alarmed if you see lots of white smoke)
This is the varnish and gunk burning off your injectors. Now drive your truck, putting the hammer down, when the white smoke has stopped you'll notice an immedate difference.
Oh yeah, I almost forgot, pour the rest in your tank and then a can in your tank about every 4th or 5th fill up. If you're carbed, pour about 1/3rd. in top of carb with hot engine running.
Then follow the above directions. Hope this helps, it's an amazing product. Let me know
email me.(

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