View Single Post
Old 12-09-2021, 08:17 PM   #8
Junior Member
cplvan is on a distinguished road
Join Date: Dec 2021
Posts: 18

2001 SL
Default Re: P0131 code with hesitation when accelerating and poor gas mileage

Originally Posted by trottida View Post
Classic S Series symptom is a low temp reading. This is about the correct reading for a GEN3 like yours; give or take a needle width.

Below is a photo showing the ECTS location with the battery removed and here is a relevant video >> I think this is a GEN2 which has a few engine bay differences but the ECTS is in the same location. There is a second photo of the difference between a brass tipped and resin sensor. You want a brass tipped in there.

Pinch the sides of the ECTS connector to remove it and use the appropriate sized socket to remove the sensor. You will loose a bit of coolant and it helps if you raise the left front corner of the car. Inspect the tip for cracks or just replace it. Inspect the pins on the connector to make sure they are clean; no coolant residue or dirt. Here's a link to a relevant video for replacing the connector >>

The thermostat typically fails open on these allowing coolant to circulate and over cooling the engine. Here's a relevant video for replacement >> and this one >>

I replaced the ECTS and the wiring looked fine and no corrosion. The problem is still there. Do you recommend replacing the bank 1 sensor 1 o2 sensor?
cplvan is offline   Reply With Quote