1995 Oldsmobile Cutlass Supreme Poor Mileage

GMC
Avatar
SHOVEITIN1987
  • MEMBER
  • 1 POST
i have a 1995 oldsmobile cutlass supreme SL, 148,000 miles. for one. i am getting really bad gas mileage and i am pretty sure its the oxygen sensors on it. now, i was told that there are 2 of them. one located before and one located after the catylitic converter. i am trying to get better performance out of this car while at the same time saving gas mileage. my question is, would taking the catylitic converter off or having only 1 oxygen sensor have any negitive outcomes on my behalf? and also, on the freeway, my "service engin soon" light comes on but only on the freeway after doing 65 for about 10 minutes. and while im attempting to accelerate to that point when i git the gas, it tends to take the engin about 3 or 4 seconds to actually raise in RPM's for it to accelerate. what could be posible causes of this?

thank you
Apr 14, 2006 at 4:58 PM
Advertisement
Avatar
LOSONE
  • ✓Experienced Mechanic
  • 1,616 POSTS
I think you have a lot more than O2 sensor problems. As a rule O2 sensors don't go out but are damaged by a rich running engine. the exception to that are sensors that have a heating element.

Have a mechanic run a good disgnostics using a good scanner. he will be able to tell the problem.

Never never remove a cat as it will upet the computer control systems and besides it's against the law in all states. The computer is dsigned to monitor 2 O2 sensors and that how it has to be.
Apr 15, 2006 at 12:34 PM
🔧 Tools & Auto Repair Parts
Find automotive tools, diagnostic equipment, and replacement parts for your next repair.
Shop on Amazon →
Paid affiliate link. As an Amazon Associate, we earn from qualifying purchases.

Suggested Repair

Have a mechanic perform a full diagnostic scan. Do not remove the catalytic converter or run with only one oxygen sensor; the computer is designed to monitor both sensors, and removing the converter is illegal and will upset engine control. Poor mileage and delayed acceleration may come from a rich condition or other faults a scanner can identify.

Conversation Summary

The owner of a 1995 Oldsmobile Cutlass Supreme reports poor fuel economy, a service engine soon light that appears on the freeway after about 10 minutes at 65 mph, and a 3-4 second delay before engine speed rises when accelerating. They suspect the oxygen sensors and ask whether removing the catalytic converter or using only one sensor would help. The expert says the problem is likely more than oxygen sensors, which are often damaged by a rich-running engine, and recommends a proper scanner diagnosis. Removing the converter is illegal and will upset computer control; the system must monitor two oxygen sensors.

Related Repair Questions

Add a reply
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.

Ask a new question

Frequently Asked Problems for This Vehicle