Rough Idle

[opfor2]

My 2011 SSV has a rough idle, It’s not bad but noticeable sometimes worse sometime not so much. I cleaned the MAF sensor with MAF cleaner, Cleaned the TB and reset it using a Bi-directional scanner, added injector cleaner to the fuel, new OEM plugs. Not sure where else or what else to try and any suggestions would be helpful.

 

[Tonyrodz]

How are your wires? Oem or have been replaced before?

 

[Doubeleive]

My 2011 SSV has a rough idle, It’s not bad but noticeable sometimes worse sometime not so much. I cleaned the MAF sensor with MAF cleaner, Cleaned the TB and reset it using a Bi-directional scanner, added injector cleaner to the fuel, new OEM plugs. Not sure where else or what else to try and any suggestions would be helpful.

injector service, if a few tanks of gas and injector cleaner does not clear it up.
just doing one dose of injector cleaner is not going to do anything, put in 2 bottles per tank full for the foreseable future.

 

[Dustin Jackson]

What quality fuel are you running? My best success with a smooth idle is tuning my tahoe to run on 91, using good 91 gas, and raised the Idle to 600RPM

 

[opfor2]

How are your wires? Oem or have been replaced before?

I have not replaced them. I will get a OEM set

 

[opfor2]

What qI just started running E85uality fuel are you running? My best success with a smooth idle is tuning my tahoe to run on 91, using good 91 gas, and raised the Idle to 600RPM

I just started running E85 and it seems to help a little to smooth out the idle.

 

[Dustin Jackson]

@opfor2 These engines try to idle as low as possible from factory which can lead to a poor experience. I've spent a lot of time and money replacing parts but nothing made a difference other than what I said above. It's common for these to idle poorly be default, especially at this age.

 

[dkad260]

When you say "Rough Idle" , are you referring to a slight shake felt when stopped in gear?

I had that after I replaced my plugs and wires and the broken LH motor mount. Had a slight rough idle before all that, but afterwards it wasn't fully cured.

What cured my "felt rough idle" when in gear and stopped....was a new RH motor mount.

Turned that shake off like a switch....felt shake anyway.

If the RH mount is worn, then it's almost like a solid mount.

 

[iboughtatahoe23]

I just started running E85 and it seems to help a little to smooth out the idle.

check my thread. Having same issue in 2014 Tahoe. I’m about in the same position as you. Gonna switch back to e85 and report back.

 

[opfor2]

check my thread. Having same issue in 2014 Tahoe. I’m about in the same position as you. Gonna switch back to e85 and report back.

I just replaced my wires with OEM's what a pain in the A$$ to pull the old wires with the heat shields. I haven't really had an opportunity to drive it to see if changing the wires helps any.

 

[Marky Dissod]

However, if it idles at the same RpM in Drive worse with petrol / better with E85, that makes me think the 20 year old injectors may be aging less than gracefully

 

[opfor2]

However, if it idles at the same RpM in Drive worse with petrol / better with E85, that makes me think the 20 year old injectors may be aging less than gracefully

I'm not 100% sure it sure seems to idle better when using E85 fuel but it still cant tell for sure for running the AC increases the RPMs. will have to run her early in the AM w/out the ac.

 

[Marky Dissod]

Older fuel injectors perform weakest at (or under) idle & @ WOT.
While the AC clutch is engaged, commanded idle RpM increases by at least 50RpM over no AC.

 

[iboughtatahoe23]

I just replaced my wires with OEM's what a pain in the A$$ to pull the old wires with the heat shields. I haven't really had an opportunity to drive it to see if changing the wires helps any.

Well now I’m not excited to change wires and plugs lol… I know you have to get around the heat shield and also deal with putting the wires in the correct order (?)

 

[iboughtatahoe23]

Older fuel injectors perform weakest at (or under) idle & @ WOT.
While the AC clutch is engaged, commanded idle RpM increases by at least 50RpM over no AC.

I usually don’t use my AC in the summer tbh I ride with windows down. Never really doing over 45

 

[iboughtatahoe23]

I usually don’t use my AC in the summer tbh I ride with windows down. Never really doing over 45

I’m always at 600 idle, or 500 in drive

 

[Fless]

Well now I’m not excited to change wires and plugs lol… I know you have to get around the heat shield and also deal with putting the wires in the correct order (?)

If you're talking about the metal shields that cover the plug wire at the plug, those are removed easily enough with hose clamp pliers or long reach angled pliers. And each coil is directly above its respective spark plug -- how you gonna mix them up?

 

[iboughtatahoe23]

If you're talking about the metal shields that cover the plug wire at the plug, those are removed easily enough with hose clamp pliers or long reach angled pliers. And each coil is directly above its respective spark plug -- how you gonna mix them up?

I don’t know, I just read that, maybe it was referring to another car. Either way I will Change plugs. I just filled up with e85 and already feel a little difference in the idle. Feels smoother.

 

[opfor2]

Older fuel injectors perform weakest at (or under) idle & @ WOT.
While the AC clutch is engaged, commanded idle RpM increases by at least 50RpM over no AC.

Well now I’m not excited to change wires and plugs lol… I know you have to get around the heat shield and also deal with putting the wires in the correct order (?)

So the idle seems a little better with the E85 and new wires, I was told that E85 has better cleaning power than fuel alone so I'm betting that my injectors are dirty. I'm going to invest in a injector cleaner like (https://www.amazon.com/-/es/Wisamic-Automotive-inyectores-combustible-25-4/dp/B075KPD5S2) and use Seafoam injector cleaner and see how that works out.

 

[j91z28d1]

I use these to pull the boots. just pull the coil side, turn the boots till the break free then grab them with pulled and the usually come right off.