Rough Idle with stall

[Iggyblazer619]

Hello,

6 months ago I bought my 05 envoy that currently has 90k miles on it. I have a lot of symptoms that all started around the same time.

the problem started with a rough idle that was pretty noticeable.Next came the engine stalling at red lights. This has happened several times. A week or so after the engine stall I noticed "hair" coming out of my tale pipe. Im not familiar with the vehicle but I am assuming that means my resonator is in the process of blowing out its packing.

Today it did something i have never noticed. I was driving, saw a cop and immediately let off the gas and gave the breaks a quick stab. When i did this i noticed the spedometer dip about 30 mph and then resume back to normal.

I know this is a lot of symptoms but I am wondering if some of them are related.

This weekend when I have some time I am going to try and clean the throttle body. Are there any tricks to this. I have also already replaced all 6 spark plugs, one had oil on it. Also does the resonator losing its packing present any problems.

Any help with my many problems would be much appreciated.

[maxwedge]

What you describe is usually caused by the TB, but other things can do this, start with cleaning the TB. That hair as you describe is not from the muffler.

[Iggyblazer619]

I plan on cleaning the throttle body this weekend when i have some time. How do u explain the speedometer jumping so crazily. Also, if the fiberglass isn't from the muffler. Where is it from and should I be worried about it?

[maxwedge]

You could have the exhaust back pressure tested thru the 02 port to see if there is any blockage, the speedo head in these trucks went bad quite often.

[Iggyblazer619]

I am guessing the back pressure test is something that a mechanic would have to do?

[maxwedge]

Yes I would say so.