“Dr. Gizmo”
By Phil Arendt
Faulty
Switch Turns On Warning Lights
Question
1
Intermittently
the brake, srs and 4X4 warning lights turn on in my 2009 BMW X3 30i with
XDrive. Also, the cruise control does
not work when these lights are on.
I’ve
gone to a dealership and independent shop. Both performed tests but were not sure of the
cause. A dealership technician did not
experience the trouble. Tests found no issues. He speculated there is a loose connection
somewhere. They wanted more time for
test drives and diagnosis.
The
independent shop did experience the lights during a drive but said the cruise
control was working fine when the lights were on. By the time the test drive was complete
everything was back to normal. They
think there is a loose connection. They
also found low voltage to a device that wavered when they cycled the
ignition. They checked the battery. It’s fine.
Now they think the switch is the cause of the trouble but are not
positive replacing it will fix the trouble.
Have
you ever heard of anything like this? Do
you think a new switch will fix it?
T.D., email
Answer
1
Low
voltage causes all kinds of issues.
Since it is likely that your vehicle has more than 100,000 miles it is
possible the ignition switch has a fault that causes low voltage. Also, the intermittent nature of the
condition lends suspicion to an issue in the switch. Tests of the switch also show inconsistent
and irregular voltage. Consider
replacing the switch. It just might be
the cure you seek.
Low
Voltage Stalls Engine
Question
2
My
2005 Honda Civic LX with a 1.7-liter 4-cylinder engine cuts out at 55 mph. This happens after driving greater than 20
miles. I have to coast to the side of
the road. I have to call my son who
comes and jumps the battery. It starts
right up when he jumps it. When the car
stalls the radio stops working and I hear a squealing sound. A mile or so later the engine quits.
I
went to a shop about the problem. They
checked the battery, ignition switch and replaced a knocking sensor. This did not fix it.
Can
you help? D.N., email
Answer
2
The
fact your heroic son comes to the rescue and jumps the battery raises suspicion
there is a voltage or amperage issue. It
seems the sound you hear might be caused by the serpentine belt. It’s also possible the radio shutting off
indicates a low voltage condition. Your
shop checked the battery and did not replace it, it seems it’s in good
condition. They might find another cause
such as a poor battery cable connection or perhaps the alternator is not
performing as designed.
Ask
your favorite shop to consider these suggestions the next time your car rolls
into their serviced bay
Time
To Probe Circuit
Question
3
The
ABS warning light turned on in my 2006 Pontiac Grand Prix GT with a 3.8-liter
engine. I had the car tested. The code said the right front sensor was
bad. I replaced the sensor and cleared
the codes by connecting the battery cables together for a full reset. I drove the car but the ABS light came back
on. This time a test showed codes for
three sensors. I replaced the ABS module
with a unit from a salvage yard. After
this the light turned back on. This time
a test showed the right front sensor was bad again. I replaced it a second time but with the same
results.
Do
you have any suggestions? R.T., email
Answer
3
Yep. This is likely due to an issue in the circuit
such as a broken wire between the right front sensor and the antilock brake
module.
Since
it appears you are an experienced do-it-yourselfer it’s time to trace
wiring. You might find a wire is
completely broken or the break might be hidden within the insulation. A wiring diagram will be of great assistance
in probing the circuits.
Car
Fails To Go Fast
Question
4
I
have a 2009 Honda Accord LX-P with a 2.4-liter engine and 118,000 miles. It hesitates when I accelerate and it won’t
go over 30 mph even if I hold the gas pedal all the way to the floor. I had it tested at an auto supply store. Codes came up for misfires on cylinders two
and three.
I
replaced the spark plugs and ignition coils.
The engine runs smooth at an idle but when I step on the gas the engine
coughs and the check engine light flashes.
What else would cause this problem?
H.S., email
Answer
4
Don’t
replace any parts based upon my suggestions unless one is verified as failed.
The
issue might be caused by a clogged catalytic converter. It’s also possible the two cylinders lack
compression due to excessive wear.
Perhaps the fuel pump is failing.
Maybe the valves need adjustment.
Maybe there is a faulty sensor such as a failed crankshaft sensor. Perhaps the circuit to the crankshaft sensor
is open and needs repair.
Once
tests find the failure repair might be as simple as fixing a broken wire.
More
Clearance Needed
Question
5
I
have a 1999 Chevrolet Tracker 2.0L with a heater blower that is making
noise. I have replaced the motor in
other car heaters but this one is giving me trouble. I have removed the bolts that secure it but
when I pull to remove it there is not enough clearance to get the fan portion
of the motor out of the heater case without breaking the fan. My new fan is a complete unit with the motor
and fan. If I break the fan taking the
old one out I’m sure to break the new one.
Is
there a trick to get this out? D., email
Answer
5
There
isn’t a trick or short cut. It’s likely
the heater case needs to be removed.
However, loosening it might provide the needed room for you to remove
the unit. Good luck with this task.
Transplant
Or Overhaul On The Agenda
Question
6
I’d
like you opinion. The automatic
transmission in my 2011 BMW X5 XDrive 35i has no forward or reverse gears. The car moves a little in neutral if I rev
the engine. I had it towed to a shop
where they found codes for transmission problems. They took off a pan and found chunks of metal
but the fluid looked clean and did not have a burnt odor. They say the transmission is shot and needs
replacement.
I’ve
owned the car since it was new. It has
109,000 miles. Do you think the
transmission is shot? N.W., email
Answer
6
Sorry
to deliver bad news but it appears your shop is on the right track. It is normal to find some metallic glitter in
the pan but chunks of metal is evidence of a broken gear or drum. If this is what they are suggesting the
transmission is suffering from a major issue and needs an overhaul or replace
it with a remanufactured unit.
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
his e-mail address drgizmo@drgizmo.ws. 01/15/2018 ® DR. GIZMO © 1989 – Present
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