Engine Vibration Is Not `Normal,’ Get It Fixed

February 27, 2010/Steve Tackett

MOTOR MATTERS ASK THE AUTO DOCTOR BY JUNIOR DAMATO

Dear Doctor: I own a 1998 Ford Ranger pickup truck with the V-6 engine that I recently purchased with 89,000 miles. The problem is a rough idle. I’ve had two mechanics check it. One repositioned the transmission lines and the other adjusted the engine mounts. The vibration is slightly better now, but I was told a vibration is normal on the both the V-6 and four-cylinder engines. Any suggestions would be appreciated. Ralph
Dear Ralph: I service many four- and six-cylinder Ford engines. I have yet to hear owner complaints about a vibration at idle. I recommend a number of checks you can do to determine the source of the vibration: Make sure the engine is idling at the correct speed; make sure the engine is running smoothly; check to see that the rubber-insulated engine mounts are in tact and that there is no metal-to-metal contact. I have seen the wrong size serpentine belt (too long) cause a vibration at idle. These are all things that need to be looked at to help eliminate the idle vibration.
Dear Doctor: I own a 2003 Toyota Corolla with 73,000 miles. My mechanic said it needed a new catalytic converter and he referred me back to the dealer because it is warranted 8-years/80,000 miles. The dealer said the front pipe was leaking which was causing the problem and it would not be covered under warranty. I went back to my mechanic and he looked at the front pipe and said there was no leak. I went to another shop for a smoke test and no leak was found. The dealer still insists the exhaust is leaking. What should I do? Jerry
Dear Jerry: My advice would be to try another dealer. If the treatment is the same, have your local mechanic make the repair using a factory catalytic converter and send the bill to Toyota and see if they will at least pay for the converter. Remember in the future there are a lot of very good brands on the market if you do not get any satisfaction from Toyota.
Dear Doctor: I purchased a 2001 Buick LeSabre with 52,000 miles. After driving it 2,000 miles the “check engine” light came on. The dealer said the problem was a faulty catalytic converter, not covered by the warranty. The cost of repair is $1,000. I went to another Buick dealer and they said it was a bad oxygen sensor. I had both the catalytic converter and oxygen sensor replaced. A couple of days later the service engine light came back on. How long can I drive the car with the service light on? What do you think the problem is? Sam
Dear Sam: Before we suggest any services, you have to use a factory GM replacement catalytic converter on this vehicle.

ford dealership

If you did not and the fault code is for catalytic converter efficiency, then you need to go back to the shop. Now you can have the technician hook up a scan tool and road test the car and observe all sensor information. Do not give up on the service engine light problem. You cannot pass a state emission test with the light on. You should also stay with one shop for service, not shop around for the cheapest price repair.
Dear Doctor: I own a 2003 Nissan Murano with 61,000 trouble-free miles, which I purchased new. For the last year the engine has make a growling sound, especially under acceleration. My local garage and I were not able to find any exhaust leaks. I had the Nissan dealer perform a diagnosis of this noise. He said I needed two new Fuel Rail Pressure Dampers. Before I replace the parts I’d like your opinion if this will eliminate this annoying noise. Art
Dear Art: Yes, I would recommend that you have them replaced. I have seen many different parts cause strange sounds. The fuel dampers act as a cushion in the fuel system and as a shock absorber in the suspension over bumps.
Dear Doctor: There is a water leak coming into the front of the car after a rainstorm. I tried running a water hose over the roof, but cannot find the source of the leak. What else do you suggest? James
Dear James: I see a lot of cars with water leaks. We take the A-pillar molding, seats and rugs out of the vehicle and run water over the area of concern. While running water a technician will look under the dash for possible points of water entry. This is a basic first step. We can also close all windows put the heater on high and use a smoke machine around the sealing areas to locate air emitting from the vehicle. Any good auto repair or body shop will be able to find the leak and fix the car. — Junior Damato, Motor Matters

Junior Damato is an ASE-certified Master Technician.

E-mail questions to info@motormatters.biz

Mail questions to: Auto Doctor, 3 Court Circle, Lakeville, MA 02347

Listen to Junior online at www.1460wxbr.com Saturdays from 7 a.m. to 10 a.m. eastern time.

Copyright, Motor Matters, 2010