Car won't accelerate over 50 mph v6-3.8l buick 1998 lesabre

Q: Car won't accelerate over 50 mph

asked by on September 08, 2017

Check engine light is on for insufficient o2 sensor activity. Just today the car would not accelerate over 50 mph at first I thought it wasn't shifting but the I noticed my engine rpm rapidly dropping (not like they normally would during shifting but more like there was some type of resistance keeping the engine from revving) and in just 2 miles the car started to over heat. With the car parked I noticed the exhaust coming out the tail pipe was intermittently stopping indicating a possible clog, I suspect clogged catalytic converter but any other input would be appreciated.

My car has 200000 miles.
My car has an automatic transmission. Only thing that has changed between when the car was running good and now is I got gas last night, is this possibly bad gas? For what it's worth I live in the Houston Tx area and we did get hit by a hurricane last week.

What you are describing sounds like you may have a clogged or damaged catalytic converter. The catalytic converter converts toxic exhaust gases into less harmful pollutants that are suitable to be expelled into the atmosphere. When the catalytic converter is clogged, this causes these gases to be backed up into the exhaust system not allowing the engine to breathe properly. When this happens, the engine is forced to work much harder to expel these gases. This often results in the engine bogging down, hesitating, shaking and causing very poor fuel economy. This should also cause a check engine light to come on as the O2 sensors should be reading the incorrect amounts of oxygen in the exhaust gases if this is your problem. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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