Cars

What’s causing my SUV to hesitate and vibrate?

John Paul, AAA Northeast's Car Doctor, answers a question from a reader having problems with a 2014 SUV.

The 2014 Honda CR-V AWD. Honda

Q. I have a 2014 Honda CR-V LX AWD with 130,000 miles. It was running great until a few months ago when it started to hesitate and vibrate at about 25 miles per hour. Once I drive above that speed it was fine. This happens if the engine is hot or cold. My mechanic tuned it up and it improved, but then after a month or so the vibration was back. I also noticed the overall power has diminished even at higher speeds. Could these items be related? Any suggestions?

A. The typical cause of this vibration is a torque convertor issue. At this point rather than replace the torque converter, which is quite costly, start with a transmission fluid change. I have seen some very good results with changing the fluid. Regarding the lack of power at higher speeds, I don’t believe these two issues are related. I would start with the basics. Check the fuel pump pressure and volume, scan tool data, and check for possible exhaust restriction and excessive combustion chamber deposits. I would also use a fuel additive such as Techron, Seafoam or BG products 44K. These products can help clean fuel injectors and combustion chamber deposits.

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Q. I have a 2013 Dodge Grand Caravan with a fuel pump that at times will run continuously until the battery dies. Do you have any suggestions outside of dropping the tank and replacing the fuel pump?

A. I would first look for a sticking fuel pump relay. Locate the relay in the fuse box (it should be marked) and swap it with another relay. Start the car, let it run, then shut it off. If the fuel pump shuts off, purchase a new relay. 

Q. I have a 1998 Cadillac Deville. I installed a speaker in the trunk and used small alligator clips to power the speaker off another speaker. I turned the car ignition to the accessory position and nothing happened. There was no sound from the radio or cassette player, so I tried to start the car. A security code came on the dash and the car wouldn’t start. I looked in the owner’s manual to see if it had a remedy. According to the owner’s manual, it said to open the driver’s side window and turn on the ignition. When the security light comes on, hit the push button door lock and close the door. The security light warning should go off. It didn’t and the car won’t crank over. The security light keeps coming on when I try to start the car.

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A. Start with disconnecting the speaker you installed. It seems from your description as if the General Motors PASSKEY system needs to reset. Typically, you turn the key to the on position and wait 10 minutes. After 10 minutes, shut the key off and then try to restart the car. 

Q. My GM cars recommend that tire rotation should be crossing the rear tires forward and bringing the front tires straight back. I suspect it’s to minimize scalloping of the tires. However the tire dealers and GM repair departments I use insist on rotating front-to-rear, rear-to-front on the same side. What is your opinion on this subject?

A. When all tires were bias ply, rotation consisted of an X pattern. Once radial tires became popular, rotation changed to moving the rear tires to the front and front tires to the rear. This was done to eliminate concerns with possible steel belt damage. Over time that has changed. Since front and rear tires have different tasks, steering, traction and braking, they can wear differently. To maximize tire wear, rotation is helpful. The suggested tire rotation and one adopted by the Tire and Rim association is exactly what your GM owner’s manual recommends. This would only vary if the tires were different sizes or a directional design. Depending on the vehicle, the tire pressure monitoring system will also need to be reprogrammed, to identify the new tire locations. 

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John Paul is AAA Northeast’s Car Doctor. He has over 40 years of experience in the automotive business and is an ASE-certified master technician. E-mail your car question to [email protected] Listen to Car Doctor on the radio at 10 a.m. every Saturday on 104.9 FM or online at northshore1049.com.

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