All LS400 owners with bad gas mileage READ THIS!
08-02-11, 09:58 AM
#151
Pole Position
I see what ya mean. Although I haven't worked on a 91, I would think it would be the same as the others. You could pull the old one and see if there's a part number on it.
Description post #158.
Description post #158.
Last edited by deanshark; 08-17-11 at 03:56 PM. Reason: deleted wrong advice
08-11-11, 11:01 AM
#152
Driver School Candidate
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.
I have a 91 also. Im having the same problem. Anybody know any solutions. I cant seem to find a part #
08-11-11, 04:01 PM
#153
Driver School Candidate
08-11-11, 07:57 PM
#154
Lexus Test Driver
Just changed my sensor on my 92 with 116,000 miles yesterday. The engine seems to rev smoother and accelerate much better. Will see what my mileage is. Lately it's been around 12-14 around town, and I live in a rural area with very few stops and no traffic. If I can't get it up, I may very well replace this car with a pickup.
08-12-11, 07:08 AM
#155
honestly, chances are you guys need to take your ecu apart and replace all the electrolytic caps. i posted a thread that showed where they are and what the values are cause i wasted money having my ecu "repaired" by ATE just to find out that all they did was replace the caps, which wasnt my problem on that particular ecu. (ended up buying another ecu to solve the problem i had).
https://www.clublexus.com/forums/ls4...-repaired.html
replacing the caps is a common need in alot of other toyota ecu's of the same era.
https://www.clublexus.com/forums/ls4...-repaired.html
replacing the caps is a common need in alot of other toyota ecu's of the same era.
08-12-11, 08:43 AM
#156
Lexus Test Driver
That sensor in your picture is def not the coolant temp sensor that we're replacing. Did you try moving the spark plug wire holder? Mine was almost all the way underneath it in the back, and I had to move it to access the sensor.
08-12-11, 07:07 PM
#157
Just changed my sensor on my 92 with 116,000 miles yesterday. The engine seems to rev smoother and accelerate much better. Will see what my mileage is. Lately it's been around 12-14 around town, and I live in a rural area with very few stops and no traffic. If I can't get it up, I may very well replace this car with a pickup.
08-17-11, 03:48 PM
#158
Pole Position
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.
08-23-11, 05:47 AM
#159
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I found your problem (another thread popped up, same issue) and figured I would post it so when people search in the future they see the answer to your problem. The sensor you unplugged is not the ECT, it's the "Start Injector Time Switch". The ECT should be located under the plastic tray for the spark plug wires. (green connector) I describe it in post #7 of this; https://www.clublexus.com/forums/ls4...too-small.html You can also see both sensors in step 27-28 of this; http://www.lexls.com/tutorials/engine/timingbelt.html Hope this helps somebody in the future.
11-12-11, 12:01 PM
#162
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Do you have any tips on getting that plastic piece off that covers the left side of the spark plug wire tray? I'm having fits with it and not sure how to proceed. Thanks
11-12-11, 12:26 PM
#163
Pole Position
11-12-11, 01:25 PM
#164
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That is exactly what I did and I have viewed the pics but none of the posts tell exactly how to get that piece out. It is really wedged in there. I need to know from someone who has taken it off before and they will know what I mean. I thought from reading the postings that you had done so. Sorry
11-12-11, 02:38 PM
#165
Pole Position
That is exactly what I did and I have viewed the pics but none of the posts tell exactly how to get that piece out. It is really wedged in there. I need to know from someone who has taken it off before and they will know what I mean. I thought from reading the postings that you had done so. Sorry
This will show where the bolts are; http://www.lexls.com/tutorials/ignition/sparkplugs.html
