Q: Hesitation when accelerating

asked by on April 14, 2017

Over the last few years, car has struggled with accelerating and seems worse now with warmer weather. Feels as though i am pulling a heavy load or going against a strong headwind; when the wind blowing it is very difficult to handle car. Has a chugging sound and is not zippy anymore. Steering (tight?) and brakes (a delay when 1st press it,like a slight coasting feeling) Appears to be misfiring and most accelerating issues are from 0-40mph. At least, one time felt like car surged/jumped forward. Within the last year, Transmission oil/drop pan change, replaced spark plugs (were originals)within a few weeks had to replace another spark plug and 1cyclinder coil. on 3rd battery since got car. Air filter change. I have NEVER had any warning lights come on, diagnostic are not throwing any codes- had misfire once; one relating to power window. I have been to 2 different Mechanic (3 including dealership) and no one can "recreate" what i am describing. Please HELP!

My car has 80000 miles.
My car has an automatic transmission.

Hi There, It sounds like you may have a clogged catalytic converter that may be causing the vehicle to struggle to accelerate. There are a number of reasons that may cause the catalytic converter to fail. They include: O2 sensor, fuel injectors, spark plugs, EGR valve system, exhausts manifolds, vacuum hoses, and MAF sensors. I would suggest having all of these components checked to be sure they are operating correctly. Generally, when the motor is continuously running too rich (too much fuel), this will ultimately destroy the internal components to the catalytic converter by way of igniting raw fuel inside the catalytic converter. Despite the catalytic converter’s ability to withstand very high temperatures, excessively rich fuel conditions can produce enough heat to push the converter material beyond it’s limits. These types of rich fuel conditions result in higher than normal temperatures that can cause matting erosion and burn away or melt converter coatings. If temperatures are high enough, the ceramic substrate itself will melt and clog. I would suggest having an expert from YourMechanic come to our location to inspect these components on your vehicle to narrow down what may have caused this.

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