No Power

[Danbo2003]

hi guys i'm new to the site i was hoping someone could help me out...i have a 2003 gmc sonoma sls 4wd v6 i have been hearing a rattle under the truck for about a week or so, thinking it was the heat sheild for the catalytic converter i thought i had a little time to fix it. today i was driving and the truck started to loose power i was doing about 55mph the truck started to loose power i stepped on the gas the truck's motor revved up but no power i heard pinging and ratteling under the truck the more i drove the truck the more noticable it was. im hoping maybe the cat and not the trans...i have checked the trans fluid it was fine.. i have replaced the intake manafold gaskets, water pump, radiator, drive belt, i thank you ahead of time for any advice you can offer thank you

[Carder09]

I know that the newer model trucks will lose power when the battery is poop, but It may also be the cat and sensors, best to check both of them.

[Danbo2003]

thank you..

[Kramer]

hi guys i'm new to the site i was hoping someone could help me out...i have a 2003 gmc sonoma sls 4wd v6 i have been hearing a rattle under the truck for about a week or so, thinking it was the heat sheild for the catalytic converter i thought i had a little time to fix it. today i was driving and the truck started to loose power i was doing about 55mph the truck started to loose power i stepped on the gas the truck's motor revved up but no power i heard pinging and ratteling under the truck the more i drove the truck the more noticable it was. im hoping maybe the cat and not the trans...i have checked the trans fluid it was fine.. i have replaced the intake manafold gaskets, water pump, radiator, drive belt, i thank you ahead of time for any advice you can offer thank you

 

You would better served to ask this question in the " Ask a GM Technician" section

I don't know what it is, but it's not the battery. I doubt it is the cat, Probably transmission related.

[Carder09]

Oh, fuel pumps can rattle, though as weird as that sounds, it is possible that the pump is going out, if you can hear the rattle at idle go under the truck and listen near the pump, if its not even close to that try to pin point the sound to get a better idea of where its coming from, hopefully it isnt your trans, and catty is still an option battery not so much, my old 94 k1500 tranny didnt rattle or anything but it did do the whole rev up and not do anything, replaced the fluid and filter, found rocks, not little pebbles but rocks inside of the tranny in the pan where you remove the filter, ran good for a few months but I guess the new fluid, since it wasnt changed regularly, just did the trans in, so you might be lookin at gettin a new tranny.