Hello. My car has an automatic transmission and lately it started malfunctioning when I try to accelerate. It would work fine on the startup and then there would be rattling noise upon acceleration. It seems that it cannot shift to second gear normally, but seems to have a delay in shifting into the following gear. I think the issue is becoming worse and it seems as if it would stall occasionally. The shifting into next gear is very sluggish with noticeable rambling sounds. It gathers some speed when it finally shifts. The performance improved for a few days after I had the fuel pump replaced but now it is worse. What could cause this? How can I fix it? Thanks.
Various items can cause similar symptoms to the ones you have described. The most common would be a bad fuel filter, transmission fault, torque converter issue, shift solenoid problem, low fuel pressure, or a failed fuel injector. All of these are potential contributors to the issues you are describing which may be either separate or related to each other. If you want to have these symptoms inspected firsthand, a professional from YourMechanic will be able to diagnose your shifting issue and rattling noise to let you know what repairs should be made.
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