1999 gmc envoy starts making ringing sound when driving then if you pull over and put it into park it stops

SOURCE: Envoy shaking when stop

p0128 engine coolant thermostat below operating temp. Possible low on antifreeze. not plugged in, possible chaffed wires.

P0106 pertains to the throttle body. most cases involve cleaning the throttle body

p0614 i could not find code definition

SOURCE: wont shift back from 4x4 low, to 2x2

I also have a 2002 Envoy. Shifting to and from 4wh and 4wa can be done on the fly but shifting to 4wL has to be done stoped and while in neutral. Try that. Otherwise I'm afraid its a new computer for you. Its located under the left rear seat and you need a loan for one.

SOURCE: My 2002 Gmc Envoy is stuck in 4wheel low. I

Try disconnecting the battery for a few minutes, that might get you out of trouble for now. There are some common problems with these 4wd systems. Most common is the mode position sensor on the encoder motor. Sometimes it can be the switch on the dash. Fact of the matter is I can't tell you what is wrong without using a scantool to retrieve the fault codes from the computer controlling the 4wd.

SOURCE: whirring noise from engine area - increases with acceleration

Mine did the same. It was a bad idler pulley

Jim Goldsmith

• 2005 Answers
• Posted on Jul 22, 2010

SOURCE: 2004 gmc envoy leaking power steering fluid and

replace the leaking power steering hose