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Information Problems This
category contains featured questions as
examples. They relate to most vehicles.
Question:
2002 Ford F150 mileage: 78,000. Over the last few weeks
when I accelerate the truck will "hesitate."
It is just a quick stutter and once I let
off the gas it seems to stop. It was just
doing it when the truck was in overdrive but
now it is doing it in rural areas with the
overdrive off. I just had the fuel pump
replaced less than a year ago and the fuel
filter is fairly new also.
Answer: Your
Mass Air Flow Senor is operating below
were is should. This condition gives you low
power, replace to recheck system.
Question: 1998 Jaguar XK-8
miles: 76,000. Hi, I own a 1998 Jaguar XK-8
it has been a great car for years but now
when I take my car out first thing in the
morning it runs rough, seems low on power
and sometimes backfires. When it warms up it
seems ok. I have had all regular service
work done at the dealer so I took it in.
They charged me $122.00 to tell me they
didn't know what was wrong. They scanned the
computer but it didn't show anything and
they couldn't get the car to duplicate it.
What do I do now?
Answer: This
is a difficult problem to detect because the
computer can not sense a malfunction, the
vehicles computer system thinks everything
is ok. In reality what is happening is the
electrical component inside the
MAF sensor becomes
contaminated by air impurities. These
containments imbed themselves to the
electrical component that senses the air
flow causing the sensor to be slightly off,
but not enough to trigger the MIL
(malfunction indicator lamp). Replace the MAF sensor with a new. NOTE: (Mass Air
Flow MAF sensor or Air Intake Sensor AIS,
depending on manufacturer. It does the same
thing only with different names).
Question:
2001 Ford Contour,
mileage: 83,300. Hey guys. My Contour
has had what feels like a "missing" problem
for the past several months. Between
the speeds of 45-65 mph, the car will "miss"
on gradual acceleration. Additionally,
the car sometimes stutters on acceleration
after a stop. Both of these
problems are erratic (some times it seems
like I'm not going to make it to where I'm
going, and other times I can go days without
a problem). I have taken the car to
Ford several times, but each time they
insist that no codes have been set, and that
they cannot duplicate the problem. I
took the mechanic on a test drive myself,
but (of course) the car ran fine.
Coincidentally, my extended warranty is
almost up. I get the feeling that Ford
is putting me off until my warranty is up.
I have another appt. with Ford for March
18th, because these problems are getting
worse. I realize that many things
could probably cause the symptoms I've
described, but I'm completely without
options in the face of Ford's denial of any
problem. Either my car was assembled
on an Indian burial ground or it has a
mystery problem that doesn't show up on
Ford's computer. Any advice you could
give me would be greatly appreciated.
Answer: First scan the
PCM for trouble codes using a hand held
engine scanner, Then
repair codes by replacing failed ignition
components as needed. If no codes are
present then check the fuel pressure.
Question: 1997
Chevrolet Silverado 1500 4x4 mileage:
139,000. I cannot figure out how to
adjust the timing on my 1997 TBI 5.7. What's
the trick? Thanks
Answer: The timing is
controlled by the computer.
Question:
2002 Honda Accord, mileage:
99,000. Occasionally the car is difficult to
start. What should be done for a "tune-up?
Answer: It sounds like
you are due for a major tune-up. Replace
spark plugs, fuel filter and air filter.
Fuel injection should be serviced by
cleaning throttle bore and idle passage.
Question: 1999 Isuzu
Rodeo, miles: 78,000. I am curious about the
appropriate mileage of an overall tune up
that also includes a new timing belt, new
drive belts, all new filters, flushing and
replacing all fluids throughout the vehicle,
fuel filter, adjustment of valves, and
flushing the cooling system. This is
supposed to be a very thorough preventative
maintenance procedure. Is it a good idea at
78,000 miles?
Answer: Yes, this is a
good idea. We would also replace the
radiator hoses. The valves do not require
adjustment; they are self adjusting..
Question:
1998 Ford F150, miles: 134,000 on it and was
used as a work truck for a company. The body
is great and I understand that it was
probably put through the ringer. It was
routinely maintained (oil changes) but I can
see that wires, plugs, sensors and other
minor things were not. Being a novice do it
yourselfer, where is the best place to start
with fixing it up and replacing stuff. Any
comments and questions would be greatly
appreciated.
Answer: A major
tune-up would be a good start. Replace the
spark plugs, plug wires, fuel filter and air
filter. The fuel injection should be
serviced to clean the throttle bore and idle
passages. You may need to replace the
radiator hoses and belts. An oxygen sensor
would also be in order. Next, check the
brake system for wear.
Question: 2004 Toyota Camry
mileage: 34,000: Upon cold start-up, my new
Camry jumps to approximately 2,000 RPM for
about 5 seconds and then the Rpm's drop to
about 1,500 Rpm. I fear that this initial
jump is too high for cold warm-ups. Is this
initial jump typical of the new Camry's?
Should it be taken in? It does this every
time it is cold started.
Answer: The cold fast idle rpm is
controlled by the computer. Its sounds like
the IAC control motor is sticking or
shorted. Also
there may be a faulty
idle air control motor and/or
oxygen sensors.
Question: 2003 Honda
Accord, mileage: 46,000. I have a same
problem as listed in another posting, on
cold start the car goes into fast idle mode
and after a minute the idle starts to jump
between 1,500 rpm and 1,800 rpm. I've been
trying to fix this for a year. I've replaced
the O2 sensor and PVC valve as you told the
other poster to do. I've also replaced the
Air Temp sensor (TA), Water Temp sensor
(TW). I've stumped the dealership, as they
find nothing wrong. I even replaced the fast
idle valve and EACV! The engine has been
tuned and I have no clue what else to do?
After the engine is warm, everything is
great and runs really well and car is like
new after constantly doing the service on
time.
Answer: The
data stream from the engine to the computer
should be read to determine the values of
the various sensors on the car. In addition,
check to see if the ground wires are
properly attached and making good
connections.
New" How
to Replace"
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Fuel Filter -
Oil Filter -
Air Filter -
Radiator -
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