T-Stat and A/F Sensor Replace?
#16
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I don't have an OBDII reader let alone a SGII
. As I understand it (and I could be wrong for sure) P0125 has to do with the A/F sensor performance after the car is warmed up to normal operating temperature. The reference to "coolant temperature" is really a misnomer. Now, if the ECM thinks the car is at normal temp and it isn't, then I suppose you could throw P0125 without having a bad A/F sensor. However, I think that would point to the coolant temp sensor not the thermostat. I think having P0125 and P1130 at the same time means it is 99.99% an A/F sensor malfunction. Even though a t-stat would be cheaper than an A/F sensor, it would be a waste of time and $$ to replace it based only on P0125, IMHO.
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#17
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Art- It wasn't so much that I was suggesting that the thermostat was the culprit- just that I figured the thermostat would be a whole lot cheaper and easier to change. Looks like I was mistaken on the "easier to change" part. The reference to the Scan Gauge II was that it displays 4 digital readouts at one time (your choice) and you can use the temp to challenge the P0125 and "open loop-closed loop" to challenge the operation of the A/F ratio sensor. If it is actually going to closed loop it would seem the P1130 is invalid. If the coolant temp. sensor is bad, the SGII wouldn't diagnose that, other than a code if the CEL generated it. If I understand the codes correctly, they seem to have codes that would indicate malfunction in the CTS.
PS As you know, I am not a mechanic and know only what I read in the manual. As a result, I am often wrong but never in doubt!
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#19
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Roger, if you don't mind me asking, what did you pay for the SGII? Amazon is selling it for $160. I'm not sure I understand what you said. Is the SGII able to provide "artificial" signals to the ECM? That is, you can ramp the coolant temp up/down and observe the effect?. Also, what is CTS? Thanks.
PS As you know, I am not a mechanic and know only what I read in the manual. As a result, I am often wrong but never in doubt!![Smilie](https://www.clublexus.com/forums/images/smilies/smile.gif)
PS As you know, I am not a mechanic and know only what I read in the manual. As a result, I am often wrong but never in doubt!
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Art- I paid $135. I believe for the SGII. Because I had the original, they give you a special deal on the SGII. I only found out about it from a post on F-150online and I had to ask when I ordered it but they readily gave it to me because of owning the original. As Lenore said, only receives, no commanding. CTS is "coolant temp. sensor". Just that it will monitor CT and you would know if the ICT (insuf coolant temp) is accurate or not. The reference to Open loop-Closed loop (which is a reading you can chose to display) is that if it went from OL to CL quickly, as it normally should, it would only do that in response to proper temp input (as well as other inputs from the PCM). Either low temp or faulty low temp input will keep it in OL. I like the SGII better for simple diagnosis than the Auto- Xray 6000 that I have (great scanner) because you can leave it mounted in the car and monitor while driving and is so simple to operate. The download of all future programs at no cost is an additional attraction. Love it!
#20
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**Update** I did replace the A/F Sensor..(which was HELL to replace...) but after some time, got it out and installed new sensor, took for test drive, lights when out and everything is good to go!!!
I want to thank all of you guys for your help, I wouldn't have gotten it correctly without you!!!!
The A/F Sensor was probably the biggest cost-- set me back about 180 bucks but, it could have been worse!!!
Thanks again!!!
I want to thank all of you guys for your help, I wouldn't have gotten it correctly without you!!!!
The A/F Sensor was probably the biggest cost-- set me back about 180 bucks but, it could have been worse!!!
Thanks again!!!
Last edited by SlickVic; 09-15-09 at 07:43 PM. Reason: re-wording
#21
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**Update** I did replace the A/F Sensor..(which was HELL to replace...) but after some time, got it out and installed new sensor, took for test drive, lights when out and everything is good to go!!!
I want to thank all of you guys for your help, I wouldn't have gotten it correctly without you!!!!
The A/F Sensor was probably the biggest cost-- set me back about 180 bucks but, it could have been worse!!!
Thanks again!!!
I want to thank all of you guys for your help, I wouldn't have gotten it correctly without you!!!!
The A/F Sensor was probably the biggest cost-- set me back about 180 bucks but, it could have been worse!!!
Thanks again!!!
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#23
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#24
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Hi Thomas- how do you like the SGII? I even liked the original one, as ugly as it was. I could only stand it so long though and made a stainless partial case for it. Have you downloaded any additional programs for it? I sure like ALL the improvements they made, from the original one.
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