2001 GMC Jimmy SLS Problems. Help!

I am in love with my jimmy but i am having some problems. When my jimym is ideling, the gas gadge jumps drastically around from full to empty and such, so i am not sure what that is about. And i recently took it on a road trip from atlanta georiga to tucson arizona. and when i go to start it, it cranks for a couple of seconds before it turns over. does anyone know what is wrong with my baby?

Most likely the sender has some bad spots in it that cause the gage to read higher than normal.
The hard starting may be from fuel pressure bleed of when the engine is turned off and the pump has to build up pressure again...These engines run on about 60psi so it takes a second or two the build up pressure.

just go get a tune up, should do it if not it will let u now what is wrong easier

i have a code 300 ....multiple cylinder missfires. i just changed my catylitic convertoer and still problems....any ideas

welcome to af. this thread is now over 3 and a half years old. please refrain from posting in old threads. a po 300 is usually some kind of ignition related issue. feel free to make a new thread in the problem diagnosis section and we will be glad to help you.