Car Questions

Clear all

How to fix my 2001 Silverado?


Topic starter

Hello I have a 2001 Chevrolet Silverado 2 door step side truck 250,000 miles 4.8 litre engine. Other than the high miles the truck aesthetically looks immaculate inside and out. I know it’s high miles but I want to fix because it was my great grandfather’s truck who has since passed. 
I’m the problem I’m having is the break lights do not work the third break light works with no issue but the two taillights break lights don’t work I’ve replaced the bulbs and didn’t fix the issue and see no noticeable corrosion. 
The daytime running lights won’t work even when the bulbs are replaced. 
lastly the truck when first started misfires and has a multiple cylinder misfire it’s not burning coolant or anything I have replaced spark plugs and coil packs and it still misfires. I was told by a mechanic that it Is a vacuum problem but can’t hear any noticeable air being sucked in.  

1 Answer

Check for bad grounds, they can cause all kinds of electrical glitches and that thing is 21 years old. You'll likely need a shop manual or to find where the grounds are located. (Some libraries carry 3rd party shop manuals such as Mitchell in their reference section.)

You can use some carb cleaner to spray around potential areas that may have vacuum leaks. (Idle will change if the stuff is drawn in through a leak.) Also if running lean that should show up in live data. Misfires can be caused by anything that interferes with proper combustion - bad compression, bad fuel injectors, incorrect fuel pressure, bad electrical connections, ECU problems, and more, aside from spark plugs and coils. Head gaskets can blow without burning coolant, it depends where the flaw in the gasket is located.