"Dr. Gizmo"
By Phil Arendt
Low
Engine Power Has Many Causes
Question
1
My
2008 Cadillac CTS with a 3.6 engine is lacking power and there is a reduced
power message on my dash. I had the car
tested at an auto parts store. The
partsman found trouble codes 87 and 89.
He says I should go to a nearby repair shop because there is a problem
with the fuel pressure. He thinks a
regulator might be bad.
Do
you think this is the trouble? C.G.,
email
Answer
1
A
lack of power will put a damper on your driving experience. Codes P0087and P0089 indicate a fuel pressure
problem but the issue might not be caused by a faulty fuel pressure
regulator. There is a lot more to the
fuel system than you might think. The
fuel tank contains two modules; a primary and secondary module. The modules contain fuel pumps, filters,
level and pressure sensors.
On
the engine is another fuel pump, fuel pressure regulator and of course there is
plumbing connected to all the pumps, regulators and fuel injectors. Along with all of these parts there is the
engine control module, sensors and electrical system.
While
the trouble might be caused by a faulty fuel pressure regulator it is possible
one of the pumps is failing. It’s also
possible an electrical issue or fault in the engine control module is causing
the condition. Additionally,
contaminated fuel might be the cause.
At
this point consider limping to a repair shop to have a technician diagnose the
cause of the condition.
Oil
In Coolant No Laughing Matter
Question
2
I
was driving along in my 2005 Honda Odyssey with a 3.5-liter engine when the oil
light turned on. I pulled over and found
that the oil was low. I had to add four
quarts for the dipstick to read full. I
also noticed what looks like oil in the antifreeze jug.
I
went to a quick lube shop. I had them
flush the antifreeze and change the oil and filter. Three days later I checked the oil
level. It was low and there is a lot of
oil in the antifreeze jar. The level in
the jar is almost overflowing.
Is
there a leaky oil pipe or hose that is causing this problem? H.S., email
Answer
2
This
might be a serious condition but before getting too serious, check for an oil
cooler. If your vehicle has a cooler it
is possible a leak has developed in the heat exchanger. Unfortunately, an Odyssey is not equipped
from the factory with an oil cooler. A
device such as this typically is an aftermarket installation. If it is equipped with a cooler the part
might have an internal leak that would require replacement of the cooler or
elimination of the aftermarket installation all together.
If
no cooler is in the vehicle there likely is a crack within the engine between
the water jacket that contains antifreeze and an oil passage. Areas within the engine that could develop a
leak are the cylinder heads and engine block.
A technician will need to determine where the leak has occurred before
suggesting a repair.
If
the leak is the result of a crack in a cylinder head, the head needs
replacement. If a crack is in the engine
block, the block needs replacement.
Since the block is the main part of the engine it is likely a cost
effective repair might be installation of a low mileage engine from a salvage
yard.
Once
a technician determines the source of a leak he will be able to determine
repair cost. Since this might be a major
repair seek a second opinion from another shop and weigh all available options
before authorizing repairs.
Computer
Modules Need Reboot
Question
3
Dr.
Gizmo I hope you can help. The battery
died in my 2001 Chrysler Town and Country.
Apparently, it went dead because someone forgot to unplug a portable DVD
player in the back seat. I jumped the
battery and the engine starts and runs fine but there is one big problem. Since I jumped it, the dash is dead and the
wipers, power sliding doors, heater, and turn signals don’t work. My wife is very upset, too. I checked all the fuses. They are ok.
I
talked to a friend who knows a lot about cars.
He says that I might have fried some control modules especially if I
didn’t correctly connect the jumper cables.
I’ve jumped cars many times, including this one, and have never had this
problem before. I called a shop about
the problem. They confirmed my friend’s
suspicions.
Did
I toast the electrical system in my wife’s van?
Will replacing modules cure the troubles? M.D., email
Answer
3
I’m
ecstatic that you sent an informative email.
I did not know wives have fuses.
I’m glad your wife’s fuse is okay.
I’ll check my wife for fuses.
As
for troubles in the van, I believe that you followed proper jump start
procedures. This event may not be as
ominous as you might have been told.
Since the vehicle starts and runs fine it appears that you did indeed
follow jump start protocol. Usually with
an improper procedure the engine does not start.
It’s
possible modules have scrambled. It’s
time to reboot them. Completely
disconnect the battery for about an hour.
If you have a battery charger, charge the battery. Once time has lapsed, cross your fingers,
reconnect the battery and start the engine.
If computer modules have not suffered damage, all accessories and dash
should power on. Drive the vehicle for
ten miles straight. During the drive,
modules should go through a relearn process.
Everything should return to normal.
Low
Battery Power Impairs Instrument Cluster
Question
4
I
have a 2012 Mini Cooper S Clubman with 57,000 miles and an instrument panel
that intermittently quits working. The
trouble only occurs when I first start in the morning. Sometimes as soon as I start the panel may
not turn on. I can drive the car without
any problem. Sometimes as I drive the
instrument panel comes back to life and continues to work for the remainder of
my travels. This might happen three
times in a week and then it may not happen again for two weeks. I just don’t know when it will occur next.
I’ve
taken the car to a local shop and a dealership to have them check it out. The instrument panel checks out fine and has
not turned off for them even after starting the vehicle after it was parked all
day in their lot. They think there might
be a loose connection or bad module but they won’t be able to find the trouble
until the panel is not functioning.
Have
you ever heard of anything like this?
Any suggestions? N.A., email
Answer
4
Sure,
problems such as this have happened in the past. Perhaps you should buy a new Mini. Problem solved.
All
kidding aside, since the trouble occurs the first start of the day suspicion
points toward a low voltage condition.
If this is the cause, the trouble might be caused by a failing battery. Ask your favorite shop to test the
battery. If it fails tests, replacement
will likely cure the instrument cluster issue once and for all.
Concern
Over High Mileage Transmission
Question
5
The
transmission in my 1993 Volkswagen EuroVan has developed a hard shift. The van has 236,000 miles and never has had a
problem with the transmission. I’ve
owned it since it was new and believe it or not it’s in great condition. I will not get rid of it.
I
took it to a repair shop. They drove it
for several miles and felt how it shifted.
They did not think it shifted that bad.
They took a pan off the transmission.
They did not find excessive metal or other problems. They flushed the fluid but this did not solve
the trouble. They said not to worry. They think it shifts fine. They said to wait until it gets worse.
I
know the transmission is not shifting as soft as in the past. The gears engage much harder. If it is going bad I’d rather replace it now
instead of being stranded. Is this a
sign the transmission is about to fail?
H.L., email
Answer
5
Your
shop did not find evidence that the transmission is about to fail so don’t
worry that you will be stranded.
However, you know your van better than anyone else. You know how it feels, preforms and
handles. You know how the transmission
normally operates so what you feel is unusual.
Since
it exhibits harsh engagements it is likely a solenoid in the transmission is
excessively worn or not functioning. The
transmission has electrical solenoids that direct hydraulic pressure to
clutches and other parts. When one
falters conditions such as you describe occur.
A problem such as this can cause clutches to slip, not engage or even
miss a gear. What you describe is not a
condition that causes the transmission to not engage and leave you stranded.
Ask
your favorite shop to check the operation of the solenoids. I suspect they will find one is not working
as designed. If so, it is likely
replacing an afflicted solenoid will resolve all concerns.
Repair
Shop On Right Track
Question
6
Right
now my 2000 Isuzu Trooper is in a shop because it will not run. When I turn the key it cranks but will not
start. My shop has done several
tests. They found the spark plugs do not
spark. They tell me that the engine has
everything it needs to run except spark at the spark plugs. They say the crankshaft and camshaft check ok
so the trouble is in the ignition coils, ignition module or engine computer
module. They think the engine module is
bad but they are not absolutely sure it is the trouble. They want to replace it but if it does not
fix the trouble they cannot return the part.
I don’t want to pay for something that is not broken.
Can
you help? M.J., email
Answer
6
Your
shop appears to be on the right track.
The camshaft and crankshaft sensors signal the engine control module to
send a signal to the ignition module, coils and spark plugs. If the control module fails to send signals the
engine will not start. If they have
tested the circuit between the engine control module and ignition module, and
found it in good working order, a signal from the engine computer to the
ignition module should not be impaired.
If the circuit is sound and the computer module is not sending a signal
the engine computer is not performing as designed. If this is true, replacing it should cure the
problem and you will be back on the road as happy as a youngster in a candy shop.
Thanks
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 drgizmo@hotmail.com. 03/30/2015 ® DR. GIZMO © 1989 - Present
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