I recently started having an issue with Mike Knight, she is loping hard between 500 and 100 rpm's while sitting idle. she will kick up to around 1500- 2000 then drop back down. there have been times when i have put her in gear hit the gas and I can see the RPM's go up but it doesnt get up speed, then she will engage and jump to 3000 rpm's and lurch. It feels like i am losing compression or not building it initially. Am I right?

 

I would look into a clogged EGR, bad EGR, or it could be time to change plugs and plug wires...

 

I just took it out for a spin, when i was trying to accellirate from a light and i had to tap the gas repeatedly fluxing between 1500 and 3k rpms to get up enough compression to get speed up. then it drove as normal at 2k rpms .....

 

idle air control motor? had idle problems that got way bad quick. switched it out no problems, couple of torx bolts

 

Michael...

What year is your Monte and the motor size would also be helpful..
as I think this would help in figuring out what maybe the problem...
It maybe something as simple as a failing MAF, (Mass Air Flow sensor)
Could also be a clogged catalytic converter..
could also be a failing fuel pump, clogged injectors, Tune up maybe needed...
When the last time it had an oil change? Is it low on oil?

 

Not low on oil, I topped it off recently, that was the first thing i thought. It is an 04 v6 3800 series II engine. I thought of the MAF too. Didnt consider tune up, it's time though. I didnt think it could be as simple as that though.