| Over the
weekend I used my 2005 Buick Rendezvous to jump start a car. Over the years I have done this many times
without any trouble until now. While
the other car was cranking my car shut off.
The other car started. Since
then the dash warning lights do not turn on and the engine starts and stalls.
I had the car
towed to a repair shop. The manager
thinks the engine control module and body module are fried due to a power
surge or improper jump start procedure.
He won’t know for sure what is wrong until his technician tests the
vehicle.
I know I
followed the right jump start procedure.
What do you think is wrong with my car? D.R., email
Answer 1
Your aid to a
disabled vehicle should be rewarded and not punished with damage to your
car. The encountered trouble is likely
due to a power surge. There is nothing
you could have done to prevent this except not provide assistance. Consider purchasing a portable jumper box
from your local auto supply store so in the future you won’t have to use your
vehicle as an emergency road service vehicle.
As for the
trouble in your vehicle. It is
possible for a module to suffer from a power surge but modules are protected
by fuses so more than likely a fuse did its job and opened the circuit to
protect modules.
Since your engine
runs, albeit not well, more than likely the engine control module is
okay. More than likely the body
control module that communicates with the engine control module and manages
the dash warning lights is suffering from the event. A check of the circuit shows two fuses are
in module’s circuit. Ask your
technician to consider this when he begins trouble shooting.
Electrical
Problem Or Overhaul
Question 2
I have a 2007
Chevrolet Silverado 1500 LTZ with a transmission that shifts from first to
second gear but it will not shift into third or fourth gears. I went to a repair shop where the mechanic
found a malfunction code for a faulty speed sensor. He replaced the sensor but the transmission
still does not shift out of second gear.
Now he thinks it needs an overhaul and wants to send the truck to a
transmission shop for another opinion.
My truck has
107,000 miles. It’s in great
condition. I have followed the factory
maintenance schedule to the letter having all recommended services done on
time.
This is my
third Silverado. I have never had any
trouble with them. I usually keep them
200,000 miles. Do you think the
transmission is shot? N.B.R., email
Answer 2
I understand
your concern. After all a trans
overhaul is expensive but it sure beats the expensive of a new truck.
It is possible
there is a problem in the vehicle speed sensor circuit that needs
repair. Perhaps a fresh look into the
trouble by another technician at another shop will find an issue in the
circuit and repair it. If there is no
problem found in the circuit, the sensor relies on input from inside the
transmission. If this is the cause the
transmission needs disassembly. This
will require replacement of seals and worn parts such as clutch plates. This
is an overhaul. Let’s hope an issue in
the speed sensor circuit is the cause of all the trouble.
Power Steering
Quit A Year Ago
Question 3
The power
steering in my 2004 Audi S4 Cabriolet quit working a month after I purchased
it about a year ago. At that time I
went to a repair shop where they checked the pressure on the pump and flushed
the system. They told me the pump is
working so the trouble must be in a solenoid or steering rack. They said the system does not have the
capability to be tested by a scan tool so they need to remove the steering
rack to determine if the solenoid has a problem.
I did not
drive the vehicle all winter. I would
like to have this problem repaired before warm weather returns. I trust my shop but I’m leaning toward
taking this problem to a dealership.
What do you suggest? L.B.,
email
Answer 3
This decision
is strictly up to you. It appears your
shop is on the right track but unless they specialize in repairing Audis
there is no place better equipped to handle repairs than an Audi
dealership. I’m not saying your shop
can’t handle the repair, but it is likely a dealer has more experience and
the specialized equipment tools to diagnose and repair the trouble.
Heater Problem
Has Many Possible Causes
Question 4
For the last
week or so the heater in my 2005 Chrysler 300 is not blowing hot air all of
the time. When stopped at a light or
in traffic the heater cools down. Once
I’m cruising the heater temperature goes up.
The engine temperature gauge on my dash varies as well. It shows about 190 degrees when the engine
idles and about 220 when traveling.
This has never happened before.
I checked the
level of antifreeze in the tank. It
was down but just below the add mark.
I added antifreeze to the full mark.
This did not change the performance of the heater.
I went to my
repair shop. A mechanic checked over
the engine. He says there must be an
internal leak because there is white foam in the valve covers. He thinks a head gasket is leaking and
wants to tear apart the engine. Does
this seem right to you? D.L., email
Answer 4
It’s possible
a cylinder head gasket is leaking but it’s not time to tear apart the engine
yet. Generally a head gasket springs a
leak after an overheating event. It
does not appear that your car has encountered this condition.
Additionally,
white foam in the valve covers can develop due to fluctuations in ambient
temperature and can form overnight.
Before tearing
into the engine consider seeking a second opinion at a different shop. Also, it’s possible the thermostat has a
fault and needs replacement. Additionally,
it is possible there is a restriction in the heater core or just maybe air is
trapped in the system. In addition to
all of these suggestions it is feasible a faulty water pump is the cause of
the trouble.
Misfire Caused
By Lean Fuel Mixture
Question 5
My 2008 Jeep
Wrangler has 155,000 miles and a 3.8-liter engine that misfires. About a week ago the check engine light
turned on and the engine began to misfire.
I went to a repair shop. They
found multiple misfire codes and suggested a tune-up. I replaced the spark plugs myself but this
has not cured the trouble.
I returned to
the repair shop. Now they say the
engine is running too lean but don’t know why after several tests. Do you have any suggestions? G.G., email
Answer 5
Sure. It’s time to dump the Jeep. All kidding aside, lean fuel mixture
problems have many causes including air leaks from cracks in manifolds to
loose vacuum lines. I’m sure your shop
is looking at every possible cause using equipment such as a smoke machine to
locate leaks.
One problem
they may not consider is a failing fuel pump.
I’m not certain but I don’t think your engine has a port to check fuel
pressure and volume. If this is the
case a technician will need to fabricate a test to determine if the fuel pump
is the cause of the condition. Once
fuel pressure and volume is determined your shop will know if the pump needs
replacement. After all if the engine
is starving for fuel tests will indicate a lean fuel mixture and lean
mixtures cause an engine to misfire.
Warranty
Transmission Repair On The Horizon
Question 6
Six months ago
the automatic transmission in my 1995 Mitsubishi Eclipse failed. My shop installed a remanufactured
transmission. Now the transmission is
doing the same thing the old transmission did before it completely
failed. I called my repair shop about
the trouble. They told me to come in
so they can check out the problem.
I can be
driving along at 45 mph and the transmission will suddenly shift from a high
gear to a lower gear without any warning.
It’s feels like I’m stomping on the brakes when I’m not touching the
brake pedal and the engine revs up real high.
Do you think the transmission needs replacement again? Should I take it to another repair
shop? C.L., email
Answer 6
Consider going
back to the shop that installed the remanufactured transmission. More than likely the unit is covered at
least by a 12 month or 12,000 mile warranty.
If it needs replacement again within the 12/12 warranty period you
should not be charged for another transmission if indeed it has a fault.
Additionally,
it is possible there is another cause for the trouble but you won’t know
until your shop performs tests.
If the
transmission is the cause of the problem and you authorize another shop to
perform work, it is more likely you will pay for transmission repairs. Let’s avoid that expense.
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