Idle flucuates 1998 gmc suburban?

[peterbruhjell]

I have a 1998 gmc suburban I recently changed oil spark plugs and wires because it felt like the engine was running alittle ruff. It's now two days after I did that job now in park or in gear the Rpms flucuate from 1000 rpm in park to almost 100 rpm while in drive It feels like it will stall or it's not getting the power it needs ...... Anyone help me? Thanks!
Could a fuel pump or altenator cause this?
Just noticed the belt tensoner looks like the spring is broken causeing it to flop could this cause rpms to manuver up and down?

 

[Molson02536]

I have a 1998 gmc suburban I recently changed oil spark plugs and wires because it felt like the engine was running alittle ruff. It's now two days after I did that job now in park or in gear the Rpms flucuate from 1000 rpm in park to almost 100 rpm while in drive It feels like it will stall or it's not getting the power it needs ...... Anyone help me? Thanks!
Could a fuel pump or altenator cause this?
Just noticed the belt tensoner looks like the spring is broken causeing it to flop could this cause rpms to manuver up and down?

Dirty EGR valve, remove the EGR valve and clean it with throttle body cleaner and also clean your IAC in your throttle body. Would also be beneficial to give your Suburban a Seafoam treatment.

http://gmcowners.com/gmc-forum/showthread.php?t=13770

Good luck and read the link i gave you, it helped out Threecar

 

[HERBtheBURB]

I have the same problem with my 96 Suburban. It's throwing 2 codes, PO171 and PO174. Basically the system is running lean due to an air leak coming from somewhere before the MAF sensor. I replaced my coolant temp sensor, MAF sensor, PCV valve along with new tubing and grommets coming from both valve covers. The PCV valve and new grommets with tubing seemed to help but the problem is not completely fixed. I guess the next step is to remove the EGR valve and clean it. Any other suggestions would be great