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hey guys, ive been having issues with my foxbody

(NW)Drake

who said that getting old sucks :-P
these are the code i have been reading as of today. i will reset them after im done posting this, the only KOEO test code is DTC 11. DTC 33, 41 and 66 are CM. The Following are KOER test DTC12, 21, 41, 91, 33, 18.2012-04-08_18-14-25_375.jpg2012-04-08_18-14-28_619.jpg2012-04-08_18-14-38_804.jpg2012-04-08_18-14-44_233.jpg2012-04-08_18-18-54_892.jpg2012-04-08_18-19-01_877.jpg2012-04-08_18-19-06_98.jpg2012-04-08_18-19-10_817.jpg2012-04-08_18-19-14_932.jpg
 

wickedstangs

Chula Vista, CA
Staff member
Administrator
For my Code 41 / 91 I did the below... Turnout to be my 19 wire not in the right position..
41 - System Indicates Lean -passenger side(R), No O2 Sensor Switching Detected. always lean -passenger side(CM)
91 - System Indicates Lean -driver side(R), No O2 Sensor Switching Detected. always lean -driver side(CM)

For Code 41 and 91 do a continuity test from pin 49 at the ECM connector, ECM disconnected, to a good ground source, the resistance reading should be equal/less than 5 ohms

SDC10091.JPG

Codes 41/91 (Lean Condition) specific tests:
For codes 41/91 (lean condition), it is always recommended to check the condition of the HEGO GND circuit (pin 49 at ECM connector), a bad/open ground circuit will cause lean readings from the O2 sensors. The HEGO GND is an Orange wire, with a ring connector, that goes bolted to the back of the driver side cylinder head. Identified as item #19 in the following harness diagram.

'86-'93 O2 sensors are 3-wire setups, eventhough the following chart shows a 4-wire setup, the tests can be performed as specified. 3-wire sensors DO NOT use a SIG RTN circuit....

mustangharness_Injectors-to-carb.GIF
 

(NW)Drake

who said that getting old sucks :-P
cool thx E, ill do it first thing tomorrow and ill let u know what shows up
 

wickedstangs

Chula Vista, CA
Staff member
Administrator
Fix the above first and the rest should clear... Keep me posted...

replaced them multiple times now. and as E had mentioned before that his had a common ground wire, mine do not they are grounded thru the exhaust

(EDIT)
The O2s them selves are grounded thru the exhaust, and the computer has a separate ground, here is the link that i found this out at

The exhaust is not a good ground... The orange wire should go to the block, thats what I did...
 

(NW)Drake

who said that getting old sucks :-P
on my multi meter i have it set at 200ohms and i get a 1.0 reading on a known good ground.
 

(NW)Drake

who said that getting old sucks :-P
So I moved the orange wire to a known good ground still the same codes... possible mechanical or the brain?
 

(NW)Drake

who said that getting old sucks :-P
Nope all stock except for k&n, msd cap, rotor and wires, msd2 blaster coil. And I have auto lite iridium plugs
 

wickedstangs

Chula Vista, CA
Staff member
Administrator
if you do not have the right mass calibrated to your injectors to can have all sorts of issues.. Post up on your find..
 
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