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clinebarger · 09-08-2009, 07:48 PM

A non-heated oxygen sensor (one wire) has to be at least 600 degrees for it to work. so the computer will go in to open loop at idle or if the engine is cold.
Thats why they came out with heated oxygen sensors to get closed loop faster and stay there. Check your MAP sensor vacuum line, fuel pressure (9-14psi) you got to have a tee that goes where the filter is. check TPS voltage 0.20-1.25vdc closed throttle to 4.50-4.99 full throttle. check the grounds on the themostat housing and intake bolts. check for vacuum leaks. hope this helps

09-08-2009, 07:48 PM	#6
clinebarger Senior Member Join Date: May 2009 Location: Fort Worth, TX Posts: 6,370	Re: Does trouble code mean automatic check engine light on? A non-heated oxygen sensor (one wire) has to be at least 600 degrees for it to work. so the computer will go in to open loop at idle or if the engine is cold. Thats why they came out with heated oxygen sensors to get closed loop faster and stay there. Check your MAP sensor vacuum line, fuel pressure (9-14psi) you got to have a tee that goes where the filter is. check TPS voltage 0.20-1.25vdc closed throttle to 4.50-4.99 full throttle. check the grounds on the themostat housing and intake bolts. check for vacuum leaks. hope this helps