All LS400 owners with bad gas mileage READ THIS!
#136
Pole Position
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I have a 2K with 170K on it. It was running fine but after your read I replaced it. It must be my imagination but after driving it only a mile I think it feels more powerful. Can that be possible? Also, I took it out very carefully but the plastic broke off and I know I was careful. Do you think its karma and it was about to break off? And if so maybe the connection was bad.
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#137
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mine didnt break when i pulled it off and i wasnt tryin to be gentle. just used a deep well socket. and i felt a diff in how much power the car had on the very first drive. a drastic change in the afr wil be noticable imidiatly!. ask anyone that has tuned a standalone. and if the ect was bad and reading full cold when the engine is fully warmed up, a new sensor will make a pretty big diff in how much more responsive the engine will be as well as the power.
#138
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i changed the thermostat as well and now i can really feel the difference when tranny shifts so smoothly. wasnt aware etc sensor and thermostat will make this much diff. engine/tranny mounts are next.
also william82, attached pic from diff thread. u see the red arrow pointing to etc sensor, but do u know what sensor is the one above to the right? (shiny brass, smaller sensor)
also william82, attached pic from diff thread. u see the red arrow pointing to etc sensor, but do u know what sensor is the one above to the right? (shiny brass, smaller sensor)
#139
Pole Position
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i changed the thermostat as well and now i can really feel the difference when tranny shifts so smoothly. wasnt aware etc sensor and thermostat will make this much diff. engine/tranny mounts are next.
also william82, attached pic from diff thread. u see the red arrow pointing to etc sensor, but do u know what sensor is the one above to the right? (shiny brass, smaller sensor)
also william82, attached pic from diff thread. u see the red arrow pointing to etc sensor, but do u know what sensor is the one above to the right? (shiny brass, smaller sensor)
#140
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all good deanshark. thnx for that. since talking about mileage, on half tank i got about 170 miles ,which i dont think qualifies as getting optimal mileage, but 1/4 tank was before ect sensor n thermostat replacement. filled up again today to measure how far full tank will get.
#142
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Hi there. You could try what I did before joining CL. I would call mechanics at small shops and tell them the symptoms your car was having when it showed up. If none, see if they would look at it and tell you what the problem is, BUT ask prior if they will have to hook it up to the machine that identifies the problem, which can be close to $100. Otherwise, is there more information that you could give the car guru's here (not me!)? God Bless, good luck, Peace and Rock n Roll.
#143
Pole Position
#144
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all good deanshark. thnx for that. since talking about mileage, on half tank i got about 170 miles ,which i dont think qualifies as getting optimal mileage, but 1/4 tank was before ect sensor n thermostat replacement. filled up again today to measure how far full tank will get.
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Being in LA. I do run the A/C. I always use premium gas. WAAHH! Help please anyone.As always, Thank all of y'all. God Bless, Peace and Rock n Roll on LC!
#146
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Hi williamb. Again sorry for naivite, but what is cat? Catalytic converter? When my mechanic had it for TB and WP jobs, would he have noticed something? Thanks.God Bless.
#147
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yes, catalytic converter. and he wouldnt have noticed it if he didnt drive it. drive it at night. and after 15-20min, pull into a parking lot and get out and look under the car. see if anything is glowing. if it is, you have a clogged up cat.
#149
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I happened across this thread while looking for EGR and PCV info about my 96 model with 130K. I have only had this car for a couple of weeks but have been suspecting that it may be running rich and may be low on power. Today I decided to check the plugs and see how they looked. They all looked very good so I just added anti-seize and reinstalled. I replaced the PCV valve and the air filter. The throttle body was fairly dirty so I gave it a cleaning while I had the intake off. Overall, I felt like I hadn't really accomplished anything so I hit the forum and found this thread. I decided to run over to Autozone and buy the Duralast temp sensor for $15.99, installed it, and buttoned everything up. It seemed to start quicker, not idle quite as high at cold startup, and settle more quickly into a low idle. On the road it was immediately obvious that throttle response was more crisp and it seems to respond with more authority to additional throttle. I also feel like the shifting is more precise in both sport and normal modes. Overall, it feels more like what I was expecting when I purchased this car. I have been averaging around 19 MPG in combined city and highway with the two tanks of fuel I have run through it. I will be curious to see if that improves and I will be very surprised if it doesn't. Thanks for the tip!
#150
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I tried to replace the ECT on my 1991 LS400, without success. First of all, the location looks nothing like the earlier photos in this thread. Mine appears to be on an angle, and there is only one sensor.
Second, the replacement part I bought (OEM part number 89422-20010) that others have used successfully (or the Duralast part SU4007) does not actually fit. In the part that is on the car, there are symmetric flanges either side of the sensor, but the SU4007 part is asymmetric, and clearly won't fit into the harness. Does anyone else with a 1991 model have the same problem? Either (a) this is not the ECT sensor, and that sensor is somewhere else on this model year, or (b) the ECT sensor for this model year has a different part number. (If the latter, I haven't been able to find it.)
Here is a photo showing the location of the sensor, and the SU4007 replacement part I bought (the brass one which is just lying there for comparison). Sorry that it is so fuzzy, but you can clearly see the symmetric flanges on the OEM part. On the replacement part the flange on the right is lower.
Second, the replacement part I bought (OEM part number 89422-20010) that others have used successfully (or the Duralast part SU4007) does not actually fit. In the part that is on the car, there are symmetric flanges either side of the sensor, but the SU4007 part is asymmetric, and clearly won't fit into the harness. Does anyone else with a 1991 model have the same problem? Either (a) this is not the ECT sensor, and that sensor is somewhere else on this model year, or (b) the ECT sensor for this model year has a different part number. (If the latter, I haven't been able to find it.)
Here is a photo showing the location of the sensor, and the SU4007 replacement part I bought (the brass one which is just lying there for comparison). Sorry that it is so fuzzy, but you can clearly see the symmetric flanges on the OEM part. On the replacement part the flange on the right is lower.