"Dr. Gizmo"
By Phil Arendt
Hubby Strikes Out
Question 1I treated my wife by detailing her 2007 Honda Odyssey. I power washed the exterior, engine and underbody. I also vacuumed and shampooed the seats and carpeting. Then I waxed the exterior. It looked like new inside and out. The problem was that after I did the work the wipers only worked on low speed, the power door locks and remote key did not work and the high beam headlights and turn signals did not work. My wife was happy that the car was clean but upset about the troubles.
I checked all the
fuses. None were blown. I disconnected the battery as I remembered
you mentioned in your column that sometimes this fixes problems but the
malfunctions did not clear. I was at a
loss. Cold adult beverages and a peanut
butter sandwich were for dinner that night.
I left the vehicle parked and two days later the van returned to normal.
Is this just a fluke? Or did I mess something up that will return
or strand my wife along the road. K.F.,
email
Answer 1
Wow, sometimes trying to
score points backfires. You could blame
this on gremlins but I don’t think she will buy it.
It’s difficult to determine
what happened but more than likely the high pressure from the power washer
forced water into an electrical device and caused the issues. Two days later whatever was wet dried out and
all is well.
It’s not likely to happen
again as long as you keep the power washer away from the vehicle especially the
engine bay and cowl area. Power washers
are great for cleaning concrete and grungy wheels but not vehicle engine bays.
On another note, flowers may
return your beloved wife to wedded bliss.
Morning Starts Out Rough
Question 2In the morning when I first start my 2008 Cadillac SRX the engine runs rough. Once it runs a couple of minutes the rough condition goes away. I took the car to my local repair shop where tests found a misfire in one cylinder. Their best mechanic replaced the spark plug and ignition coil. He also cleaned the fuel injectors and cleaned carbon deposits from the cylinders. He also checked the compression. After all of this work the trouble continues. Now he says there is something wrong with the valves in the cylinder that is causing the engine to misfire.
My car only has 28,000
miles. The rough condition does not
occur each morning. It may surface twice
in a week or once or twice a month. My
mechanic has been looking for the trouble on and off since the beginning of the
year. My question is if there is a bad
valve wouldn’t the trouble occur every day?
B.D.P., email
Answer 2
Generally, a burnt valve or
worn valve guide will cause symptoms that are consistent on a regular
basis. Be this as it may it is possible
there is an issue such as a fault in a valve lifter that does not occur on a
regular basis. A lifter may leak
hydraulic pressure. It might not pressurize
as quickly as designed. An issue such as
this could cause a cylinder to misfire intermittently.
Ask your technician to
consider this the next time you take the car in for diagnosis. Also since your vehicle only has 28,000 miles
you might ask your dealer if General Motors will help participate in the cost
of the repair. Trouble such as you
describe should not surface in such a low mileage vehicle.
Brake Job Needs More Work
Question 3I replaced the front brake pads and rotors on my 2008 Ford Fusion. After driving the vehicle for about a week the brake pedal began to feel soft and it would sink nearly to the floor. Also, the ABS light turned on. Immediately, I checked the fluid in the master reservoir but it was full.
Next I stopped at a repair
shop. They checked over my work and
checked for fluid leaks. They didn’t
find any problems. They thought air is
in the lines but I never opened any lines when I replaced the brakes. They also think there might be something wrong
in the ABS pump module or it might have air in it but they don’t have a scanner
to test it or run a program that can bleed the module.
My car has 77,000
miles. Do you have any suggestions? J.,
email
Answer 3
At this point it’s important
to have the brake system returned to full function. While you did not open the hydraulic part of
the system a full flush of the system might return normal operation. It’s also possible there is a fault in the master cylinder or ABS module.
Flushing the brake fluid while cycling the ABS pump with a scan tool commanding the unit might be the cure. Since the shop that examined your work does not have the tools to perform these tasks it’s time to find a shop that can.
A/C Turns Warm During Long
Drive
Question 4I have a 2001 Mercury Sable GS with a problem in the air conditioner. When I have traveled a while the air condition blows hot and cold at the same time. Around town during short trips the a/c works normally.
I went to a repair shop to
have them look into the trouble. A
mechanic did some tests but there were no computer codes and the a/c was
working normally. He does not have any
idea what causes the trouble. He
suggested waiting until the trouble becomes worse.
Do you know what’s
wrong? H.D.R., email
Answer 4
The symptoms seem to point
toward a troubled blend door. It directs
air that blows over the air conditioning evaporator core and heater core. If this moves once the controls and
temperature are set there is an issue that might require replacement of the
part.
Another area to investigate
is the control head. Sometimes faults
here cause symptoms such as this. Tests
with a scan tool should show if there are any inconsistencies as the tool
commands the various heating, ventilation and air conditioning modes. If it fails to function as designed during
tests, it’s time to replace it despite the lack of malfunction codes.
Wrong Part Or Improper
Installation Impairs Antilock Brake System
Question 5
A week ago, a front wheel
bearing failed in my 2003 Mercedes-Benz E320.
After the work the ABS light turned on.
I returned to the garage where they tested the brake system. A mechanic thinks there is something missing
at the front wheels that a sensor uses to determine the speed of the
wheels. The shop says they installed
parts from a dealer so nothing should be missing. They said I need to leave the car so they can
disassemble the wheels to determine what is causing the trouble. I need the car so I declined to leave it but I
will soon return to the shop.
Do you know what’s
missing? C.J., email
Answer 5
More than likely there are
two possible causes. The part that the
wheel sensor uses to determine wheel speed is a reluctor. This part is within a seal near the bearing. It’s possible that the mechanic was given an
incorrect part that does not have a reluctor or the installation of the seal is
not proper causing the air gap between the reluctor and wheel speed sensor to
be too great.
Your technician will know
for sure what is causing the trouble once he disassembles the wheel hubs.
Misfire Leading To
Installation Of Used Control Module
Question 6The 3.4-liter engine in my 1997 Toyota T100 pickup is misfiring. My mechanic has replaced the spark plugs, spark plug wires, ignition ignitor and coils. He also has swapped fuel injectors, checked the compression in the cylinders, tested the camshaft sensors and much more. All his work is in vain. The engine still misfires. Now he is fairly certain the engine control module is bad but he is having a difficult time finding a new one. He thinks he might be able to find a used or remanufactured part.
Will a used module be
reliable? J.B.M., email
Answer 6
A salvage yard unit might
perform fine perhaps for many years. The
only way to find out is to install it.
It may or may not function. A
remanufactured unit is renewed and tested under controlled conditions at the
remanufacturing company.
Before you authorize the
work compare the warranty policy and cost for both units.
Thank you for all the great
questions. Dr. Gizmo can’t wait to
answer more.
Phil Arendt is a columnist, consultant and A.S.E.-Certified
Master Technician. Readers may send
questions to Dr. Gizmo at P.O. Box 548, Cary, IL. 60013 or e-mail address mailto:drgizmo@hotmail.com. 09/02/2013 ® DR. GIZMO © 1989 - Present
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