This 02 saturn vue V6 STARTS up and idles but will not reb i think is timing belt there is a lot of codes po638 TAC command performance p2100 atc motor p700 trans many other codes.vaccum is 12 inches at idle.i try diferent tb same.check 40 pin cnnector by the left door still the same.nex i will check timing belt.any ideas?

Idle air control motor probly bad..its rite in back of throttlbody..wack it fewtimes w wrench it often gits betta. Its caysin a vacuumleak. jyst replace w new one..it about time..

2002-2003 3.0 L 54-Degree V6 181 hp (135 kW) 195 lb·ft (264 N·m)
Both years use timing belts. Reference Rockauto.com

it would be because its a V6 so has two banks set at 60 degrees too each other follow this u-tube link as gives an excellent view of why
Timing Marks Saturn Vue 3 0 Litre V6

For exact step by step dual cam timing mark setting.Click the link below :----http://technoanswers.blogspot.in/2012/02/saturn-vue-30-dual-over-cam-timing-mark.html
----------This will help.Thanks.

I have a 2002 saturn vue. Same thing..sounded like a jet engine ...loud humming as I accelerated . It got increasingly worse. It turned out to be the front wheel bearings. Replace them, now the noise is half as loud...have to do the rears also! 93,000 miles on it. Also, don't forget to replace the timing belt. It it goes too long and breaks, it will trash the engine...

Time to change AKK belts also. Note thge timing belt service schedule in the owners manual.

make sure you have no hoses on the engine that fell off listen for a hissing at idle. If all ok and you checked for codes which should be done before any parts are replaced then the most likely cause is the Idle Air Control Valve. (IAC). IAC's usually wont set a code.

My instrument panel is doing the exact same thing. It started today. I almost think it may be a loose cable to the computer that drives the lights. Did you ever resolve your issue?

check the cranshft position sensor and the idle position sensor.

just completed a plug removal and install on my '02 awd v6. if you have the time and patience it's straight forward; common sense was most helpful. to gain access to the plugs, both fore and aft, you must remove, in short, everything near to, associated with, the air intake system. common tools plus a 1/4 socket, with 8 inch extension to hold a #10 star bit. these star bolts are under the rectangular plastic plate atop the intake. once you have those out, disconnect all the wiring, carefully. lift the intake out, look for plug covers, fore and aft, ignition assembly lays atop each row of three plugs. with the hands of a surgeon, remove the ignition assembly, and by golly ye shall see your reward. easy from then on.
replaced my plugs with the iridium 'honeys'; marked improvement in starting, acceleration, smoothnes, noise, and gas mileage to the value of + 3.0%. changed out the oil with mobile1 extended performance, changed transmission fluid. took a shower. time involved, 7.0 hrs. dealer be damned,,priceless!