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Car Tune Up Questions
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.
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