Q: My truck is running sluggish

asked by on October 05, 2016

I changed my spark plugs and wires, some of the plugs had non foulers on them. I first left some of the non foulers out, because some of them did not have any oil on them. When I started my truck up it wasn't really missing or anything. But when I go down the road, it runs kinda sluggish so I put non foulers back in, and it still runs sluggish. Any suggestions? Thank you.

My car has 165000 miles.
My car has a manual transmission.

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Hi there, thanks for writing in. If the engine had non-fouler plugs in it then you need to do a compression test. If the engine is worn then it will need these plugs and may not be able to produce good power. Most of the time though if there is no oil on the plugs and if the compression is fine then this may be a sensor or fuel system issue. I usually check the fuel pressure first to make sure that the fuel pump is fine. I also change the fuel filter if that has not been done recently. If the fuel system is fine then I test the MAP sensor as this is a common failure and will cause a low power issue. If you want to have this low power issue taken care of, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.

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