Stumped on ambient air temp sensor issue.
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Joined: Oct 2017
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2066 e55
Stumped on ambient air temp sensor issue.
Ok from what I thought I understood about the ambient air temp sensor is that it does not impact performance but I had noticed that my temp was showing 185 degrees but things were mostly working fine in terms of performance, the SC would kick in and things would accelerate as normal. So today I went to see what was up with the sensor and found that it was missing. There was a wire going to the fog light that had two wires just hanging out with nothing attached, I'm assuming those are where the sensor should be attached, I noticed they were shorted together so I decided to separate them until I could get a pigtail with a connection to a new sensor (and boy that pigtail was not easy to find). So I got in the car to take a drive and now the temp gauge shows -45 and the kicker is that it will not engage the SC.. So unless something else happened while I was underneath the car the ambient air temp sensor seems to impact performance, is this correct or am I nuts?
Thanks in advance.
tr
Thanks in advance.
tr
MBWorld Fanatic!
Joined: Mar 2006
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From: San Jose area
'19 E63S sedan
Ok from what I thought I understood about the ambient air temp sensor is that it does not impact performance but I had noticed that my temp was showing 185 degrees but things were mostly working fine in terms of performance, the SC would kick in and things would accelerate as normal. So today I went to see what was up with the sensor and found that it was missing. There was a wire going to the fog light that had two wires just hanging out with nothing attached, I'm assuming those are where the sensor should be attached, I noticed they were shorted together so I decided to separate them until I could get a pigtail with a connection to a new sensor (and boy that pigtail was not easy to find). So I got in the car to take a drive and now the temp gauge shows -45 and the kicker is that it will not engage the SC.. So unless something else happened while I was underneath the car the ambient air temp sensor seems to impact performance, is this correct or am I nuts?
Thanks in advance.
tr
Thanks in advance.
tr
Edit: I see online that it's easy to buy a sensor with a replacement socket so I guess this is a common thing.
Last edited by whoover; Nov 10, 2019 at 01:53 AM.
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From: SOCAL
2004 E55
Ok from what I thought I understood about the ambient air temp sensor is that it does not impact performance but I had noticed that my temp was showing 185 degrees but things were mostly working fine in terms of performance, the SC would kick in and things would accelerate as normal. So today I went to see what was up with the sensor and found that it was missing. There was a wire going to the fog light that had two wires just hanging out with nothing attached, I'm assuming those are where the sensor should be attached, I noticed they were shorted together so I decided to separate them until I could get a pigtail with a connection to a new sensor (and boy that pigtail was not easy to find). So I got in the car to take a drive and now the temp gauge shows -45 and the kicker is that it will not engage the SC.. So unless something else happened while I was underneath the car the ambient air temp sensor seems to impact performance, is this correct or am I nuts?
Outside Air Temp is part of the speed density calculation that the ECU does in order to properly fuel the motor. the car will NOT run correctly without a properly functioning OAT sensor
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From: SOCAL
2004 E55
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From: San Jose area
'19 E63S sedan
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From: N.Y. L.I.
04 E55 AMG BLK/BLK(MyDD), 06 CLK 500 (wife's) 07 ML500, 2012 C300(son's)
LOL then Boowho....
IMPORTANT COLD WEATHER INFORMATION
"In order to achieve the low noise level of Lysholm superchargers, Lysholm specifies manufacturing procedures that call for minimal internal clearance. These precise tolerances however are not conducive to temperatures below 25° F. Therefore, storing the vehicle in a heated garage and/or employing the use of an engine block heater/aftermarket engine blanket is required when the vehicle is subjected to a "cold startup" in ambient temperatures below 25° F. Failure to comply with this may result in immediate supercharger failure and invalidate the supercharger warranty."
IMPORTANT COLD WEATHER INFORMATION
"In order to achieve the low noise level of Lysholm superchargers, Lysholm specifies manufacturing procedures that call for minimal internal clearance. These precise tolerances however are not conducive to temperatures below 25° F. Therefore, storing the vehicle in a heated garage and/or employing the use of an engine block heater/aftermarket engine blanket is required when the vehicle is subjected to a "cold startup" in ambient temperatures below 25° F. Failure to comply with this may result in immediate supercharger failure and invalidate the supercharger warranty."
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Thread Starter
Junior Member
Joined: Oct 2017
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2066 e55
Ok what should I expect in terms for performance if I put it back to the shorted out configuration (temp shows 185)? This was how I found it last week, the car mostly ran fine but under WOT and at about 110+ mph it seemed to have a misfire and would go in to limp mode, haven't pulled codes when in that condition was just assuming a coil pack/plug wire issue.
thanks
thanks
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MBWorld Fanatic!
Joined: Mar 2006
Posts: 4,278
Likes: 377
From: San Jose area
'19 E63S sedan
Ok what should I expect in terms for performance if I put it back to the shorted out configuration (temp shows 185)? This was how I found it last week, the car mostly ran fine but under WOT and at about 110+ mph it seemed to have a misfire and would go in to limp mode, haven't pulled codes when in that condition was just assuming a coil pack/plug wire issue.
thanks
thanks
MBWorld Fanatic!
Joined: Aug 2012
Posts: 1,790
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From: DownEast Maine
CLS 55 AMG E500 ML320
LOL then Boowho....
IMPORTANT COLD WEATHER INFORMATION
"In order to achieve the low noise level of Lysholm superchargers, Lysholm specifies manufacturing procedures that call for minimal internal clearance. These precise tolerances however are not conducive to temperatures below 25° F. Therefore, storing the vehicle in a heated garage and/or employing the use of an engine block heater/aftermarket engine blanket is required when the vehicle is subjected to a "cold startup" in ambient temperatures below 25° F. Failure to comply with this may result in immediate supercharger failure and invalidate the supercharger warranty."
IMPORTANT COLD WEATHER INFORMATION
"In order to achieve the low noise level of Lysholm superchargers, Lysholm specifies manufacturing procedures that call for minimal internal clearance. These precise tolerances however are not conducive to temperatures below 25° F. Therefore, storing the vehicle in a heated garage and/or employing the use of an engine block heater/aftermarket engine blanket is required when the vehicle is subjected to a "cold startup" in ambient temperatures below 25° F. Failure to comply with this may result in immediate supercharger failure and invalidate the supercharger warranty."
Senior Member
Joined: Sep 2017
Posts: 499
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From: N.Y. L.I.
04 E55 AMG BLK/BLK(MyDD), 06 CLK 500 (wife's) 07 ML500, 2012 C300(son's)
And yes, these beasts are hot blooded and love running in the cool/cold weather!
Last edited by Pmarino; Nov 13, 2019 at 09:33 AM.
Senior Member
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From: Dawesville, West Australia
2006 E55, 2006 SL55, 2006 LS7 Ute
Both my E55 and SL55 show OATs which appear to be much higher after parking while hot and moving again due to heat soak in the engine bay I presume. Both cars run well without issues. Where is the OAT and is it the same sensor the ECU supposedly uses? I cannot see why the ECU would use OAT except possibly at start-up when the OAT number is accurate..
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From: New Zealand
Cars use the intake air temp sensor in the charge pipe to calculate air charge. Outside temp is irrelevant once it goes through a supercharger and intercooler. I thought the outside one was for your dash display and maybe to disengage supercharger clutch in cold weather as mentioned above.
