lean then rich, a/f ratio will not stabilize

[07gt6816]

my car is running like crap right now, my wideband just jumps back and forth from really rich to really lean and just keeps going back and forth. a couple weeks ago i went through the octane booster problem but after draining the gas and swapping the plugs the car seemed to run ok but i didnt drive it very long since i was putting a motor in that weekend. i have got a few fault codes, one is bank 2 sensor one stuck lean and the other is bank one sensor one stuck rich. i data logged it and see the short term trims going lean and rich on both banks. im starting to think that both o2 sensors got screwed when it was running rough after the octane booster. anyone have other ideas? i did search, found problems about those codes but did not find anyone with both

 

[irishpwr46]

sounds like the 02 sensors got fouled up

 

[07gt6816]

thats what im thinking, i was just trying to see if anyone had any other ideas before i bought them.

 

[JeremyH]

thats what im thinking, i was just trying to see if anyone had any other ideas before i bought them.

Nope same idea, 02 sensors is a good place to start lol

Oct booster will can def reek havoc on o2 sensors.

 

[07gt6816]

sounds good, thanks guys

 

[JeremyH]

Tousley ford is the cheapest place i have found for parts if you looking for a place to buy as well.

 

[NastyStang113]

Are you saying the A/F jumps back and forth at WOT? What octane booster did you use?

 

[lito]

Have you done any work that involved removal of the front sensors? I ask because it looks too much like swapped sensors (swapped from left to right)

 

[07gt6816]

no it jumps back and forth at idle, 104, not sure of the brand. i had them disconnected but did not remove them from the manifolds so i know they didnt get swapped

 

[05yellowgt]

It IS possible to plug the left side sensor into the right side harness plug and visa versa.

 

[07gt6816]

ill double check

 

[TexasBlownV8]

The a/f will fluctuate between lean/rich under idle and normal part throttle operation, typically three times every 2 seconds. That's normal. You can easily see it on datalogging. ST fuel trims will also vary as well within a range: mine varies.

It's under WOT where the air/fuel should stay fairly level: it won't be jumping back and forth.

 

[07gt6816]

you guys are good!! i just swapped the harness and took a spin, that fixed my problem, i guess when you have three techs putting a motor back in within a few hours something is bound to get mixed up. thanks guys

texas: thanks, i know it will fluctuate slights but it was going from 9afr to 21afr, lol a LITTLE to much fluctuation. at least its fix now

 

[TexasBlownV8]

WOW, 9-21 is too much of a range indeed!!!

Glad to hear you got it fixed.

 

[JeremyH]

Sweet, glad it was an easy fix.

 

[lito]

It IS possible to plug the left side sensor into the right side harness plug and visa versa.

Thank you for putting it clearer.

you guys are good!! i just swapped the harness and took a spin, that fixed my problem, i guess when you have three techs putting a motor back in within a few hours something is bound to get mixed up. thanks guys

texas: thanks, i know it will fluctuate slights but it was going from 9afr to 21afr, lol a LITTLE to much fluctuation. at least its fix now

Hego swap is much more common that everybody thinks, also, they are much more stronger than everybody gives them credit too.

 

[05yellowgt]

Not a problem Lito. Just promise not to ask me how I know its possible to get them switched.....