After you open the hood, look straight down and it will be a stainless steel cylindrical wired sensor coming out of the exhaust manifold.
I have a 1991 LeMans, all I had to do was go to Autozone.
The 1991 Pontiac Grand Prix oxygen sensor is located on the outside of the air filter housing. You will find the sensor on the back side of the air filter housing.
8.1 US quarts
I have a 1990 Pontiac LeMans with a 1.6 Daewoo motor. The firing order is 1-2-4-3
Try eBay for a cheap factory shop manual. It is in mine.
Unplug it then unscrew it then put anti seize compound on the threads of the new one and screw it in.
Manual: 29 mpg / 38 mpg Automatic: : 27 mpg / 33 mpg
You should ask a more specific question. The drive-train includes everything from the engine to the wheel hubs.
Try a engine reconditioning shop where they sell rebuilt engines, look in the yellow pages in your area.
It has ( one oxygen sensor ) on the 1991 and 1992 Ford Explorers
motorcraft . com just shows ( 1 ) oxygen sensor for all available engines in a 1991 Ford Ranger
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