Q: 2003 Chavy Trailblazer wil not accelerate over 40 mph

asked by on April 21, 2017

Hello, we were moving and before we moved we had a rather extensive tune up on our trail blazer, we were towing a small 5'8 uhaul, it was running like a champ our whole trip until going up hill, my husband seemed to be changing gears and it just wouldn't go past 35-40 mph and in regular drive it will go 15-20 unless you really push it to go 40mph at 3,000rpm.. Otherwise In 2nd gear it will go 35-40 mph. I don't know what to do! We are really low on money.. And it's our only car! Help please! We had the transmission fluid flushed and changed it did no help

My car has 200000 miles.
My car has an automatic transmission.

Catalytic Converter Replacement $291.63 - $3264.16 Get a Quote

Hi There, What you are describing sounds like you may have a clogged 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 replace your catalytic converter.

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