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Vehicle Has Loss of Power Hesitating - This category contains featured questions
as examples. They relate to most vehicles.
Question: 1993 GMC 3500 mileage: 138,000. I am having a pinging
problem while driving down the highway at 55 to 60 mph, flat road, also when I put
my foot into it to pass, sometimes. Also when starting out whether the engine is
warm or cold driving back on the freeway it's as if there is lack of power, sputtering
as if it just doesn't want to go and then after a minute it will start to speed
up fine. This is an intermittent problem as it doesn't always happen. Have taken
it to the dealer twice. First time they changed the fuel pressure regulator. Engine
has never set a code so they are also at a loss. Sometimes it does it sometimes
not. The engine seemed to work for a few hours after they changed the fuel regulator,
but on a trip the problem returned again. Have tried different levels of octane
fuel, changed fuel filters, air filter is fine. When it starts to ping it will do
it when the engine reads cool or warm, I just climbed through Mt. Shasta and had
no problem with pinging, though sometimes when I tried to pass it once again seemed
to lack power and then just take off and run fine. I'm at a loss and the dealer
has no ideas. Any suggestions on what I could trouble shoot to solve this. Dealers
answer has been to drive it till it gets worse, which will probably happen when
I'm on a trip. Thanks for any help.
Answer: It sounds like a fuel pump is starting
to fail. It is common for fuel pumps to fail at the mileage your truck has on it.
Replace fuel pump and fuel strainer (attached to the bottom of the fuel pump) with
new to repair problem.
Question: 2002 Dodge 1500 Ram Truck
mileage: 72,000. I have recently replaced all of the oxygen sensors, fuel pump,
fuel filter and fuel regulator and the car still has no acceleration power on the
highway. I need to know if it is some I can do it myself I live in Fargo,
ND. I look forward to hearing from you. Thank you in advance for your
time and your cooperation.
Answer: Your lack of acceleration is probably caused
by a partially plugged catalytic converter. Remove to inspect, replace as needed
to recheck system.
Question: 2002 Chevrolet Suburban mileage: 110,000.
One day I stopped my suburban and went inside. A couple of hours later, I went back
outside to leave, and it wouldn't start. So, I looked around for the source of the
problem and I found that it wasn't getting any fuel. I found out the fuel pump wasn't
working, it just went out. So I changed the fuel pump. After that I started it up
and it idled just fine. But if I would rev it up it seemed to get bogged down and
backfire. So I checked the sensors, and I also hooked up a code scanner to it, it
said there was a problem with the O2 sensors. So I changed them, that was $180.
That didn’t solve my problem. So I did some tests on the pollution devices and different
sensors, but they all checked out. So, I called a mechanic he said it may be the
fuel pressure regulator and fuel filter, so I changed that, and that didn’t fix
it. I was hoping you could possibly give me some ideas on it.
Answer: If the fuel pump you installed was not OEM original
equipment manufacture, that is the problem. The fuel pressure it takes to run you
vehicle depends on 60 psi fuel pressure constant. Inexpensive fuel pumps are that
way for a reason, there are not as good and cannot hold pressure. Replace fuel pump
with OEM fuel pump to repair problem.
Follow up from Steve: Also cheaper fuel pumps don't last half
as long, even if they do run. Take that from me, with the family in the car on the
way to Nevada and we are stuck in a gas station. The fuel pump that I just installed
had failed. So much for the LIFETIME WARRANTY ~@@**%$, It doesn't help much when
your car is broke down.
Question: 2003 Toyota 4
Runner mileage 85,000. I noticed that the truck had lost some power, I had the timing
belt done back at the recommended 70K. Anyway it pulls strong, but seems to have
some very minor break down on the top end...perhaps about 4500 rpm or so. It is
faint but as I build and race cars (Camaros) I notice it. You can hear the motor
rev and it does accelerate but not as strong as it should...almost sounds as if
it is bogging a little, but seems to be more of a breaking down (loss of spark)
than anything else. I am thinking it is coil related? The truck has three coil packs
one fires one plug on one bank as well as the other on the other bank. The truck
is completely drivable, does not have any skips or misses, however seems to have
some break down as mentioned. Any thoughts are greatly appreciated...I drive the
car pretty easy but noticed the problem when goosing it onto the highway. The car
does not pull any codes.
Answer: It sounds like its time for a tune up,
spark plugs, air filter, fuel filter service fuel injection system, recheck system.
Question: 2002 Pontiac Grand Am (quad 4) Mileage: 58,000.
My mechanic is a professional auto tech and he has had my car for 2 weeks now. He
has checked all sensors, the computer, the ignition coils, the catalytic converter,
and can't figure out what is wrong. The car starts but misses and only goes to about
10-12 mph with backfiring and a burning smell. I believe it is the ignition coils
because two of the spark plugs are not firing; any insight would be appreciated.
Answer: Replace the ignition coil housing as they have a tendency
to short out on this model.
Question: 2002 Mazda Protege mileage: 89,000. When driving
home from work, I noticed lack of power. Then, after stopping at a light, my rpms
dropped dramatically, and at acceleration, the car jumped and jerked until I got
to approximately 20-30 mph. At the next light, it stalled. I replaced the plugs,
and the fuel filter. I know it sounds like the fuel injectors, but in Park, it idles
fine. Is this normal? Also, in Reverse, it seems to run fine as well. People have
told me it might be the transmission, but I doubt this because the way the tachometer
bounces like that.
Answer: Check the rubber intake boot that connects the fuel
injection body to the intake manifold. It connects to the Mass Air Flow Sensor If
it has a crack or tear, it must be replaced.
Question: 2002 Chevrolet Cavalier mileage: 80,000. If you like a good
mystery you'll enjoy this question. My Cavalier drives along smoothly at 55 mph
on level ground but as soon as I start to take it up a hill it cuts back to around
35 mph. I can even get a running start at 65 mph, but the car does the same thing,
it bogs down on the uphill incline. The following things have been tested or replaced
all to no effect. The engine compression is good, the vacuum is good, and spark
is good. A diagnostic machine shows everything is in good order. I have replaced
the fuel filter, catalytic converter, muffler, the map sensor and also the idle
air control valve. I changed the transmission filter and replaced the fluid. I replaced
the air filter. I check the egr valve to assure that it was functioning properly.
The computer has been replaced and that didn't help the problem either. Please help
before the guys in white coats come to take me away!
Answer: It sounds like a fuel pump is starting to fail. It is common for
fuel pumps to fail at the mileage your car has on it. Replace fuel pump and fuel
strainer (attached to the bottom of the fuel pump) with new to repair problem.
Question: 2000 Ford Ranger super cab mileage: 147,470. I have been driving
this truck for quite some time now. Up until recently, I have never had a problem
with power or acceleration. Even though this truck has a lot of miles on it, it
always had plenty of get up and go. Now it stutters, and almost refuses to go up
hill, no matter the grade. If the hill is too steep, I have to keep it in second,
and go 25. I just replaced the spark plugs, wires, distributor cap, gas filter,
oxygen sensor, gas tank fuel line, oil filter, and heater coil. So far, none of
these replacements have helped, but they were needed. Any idea what might be wrong?
Answer: It sounds like a fuel pump is starting to fail. It is common for
fuel pumps to fail at the mileage your car has on it. Replace fuel pump and fuel
strainer (attached to the bottom of the fuel pump) with new to repair problem.
Question: 2002 Volkswagen Jetta mileage: 45,000. Since purchasing
the vehicle in June 2002, I have never really been pleased with its performance.
It always felt more 'sluggish' than I had expected. In March of this year, we had
a new catalytic converter fitted, which improved the speed/power of the car for
a period of 2-3 weeks. It was like driving a new car...Gradually the power and the
performance of the engine deteriorated to the point where we now find ourselves
with a concentrated problem @ 2-2,500 revs. (The best way to describe the problem
is like a judder - almost as if the car is thinking about what it has got to do
for a second!). It has also been described as a lean stumble, hesitation...etc.
etc. The car has had new plugs, HT leads, ECU, Throttle switch, Air Mass Meter,
Full service and has been back to the Ford Dealer where we purchased the vehicle.
And to an Independent Engine Management Specialist! We are at the point that as
far as we are being advised every possible component has been checked / changed.
We have even put Silicon Grease on the plugs/lead at someone recommendation. Have
you got any ideas? I am pulling my hair out. Everybody I speak has got a different
opinion. Thanks Tracey
Answer: It sounds like a fuel pump is starting to fail. It is common for
fuel pumps to fail at the mileage your car has on it. Replace fuel pump and fuel
strainer (attached to the bottom of the fuel pump) with new to repair problem.
Question: 2002 Toyota Tundra mileage: 76,000. Problems started
at about 65,000 miles. The truck loses power, acts like it is not getting fuel.
Replaced oxygen sensor, fuel filter, and did tune up. Helped but still did not get
rid of the problem. Computer says the right side oxygen sensor is running rich.
Checked the EGR valve and it seems to be operating correctly. What could the problem
be?
Answer: This is difficult because the computer can't detect
the right problem, your car thinks everything is ok. In reality what is happening
is the electrical component inside the MAF sensor becomes contaminated by the impurities
in the air (heavies) These containments imbed themselves to 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
sensor and you're problem will go away, plus your car get better mileage and performance.
(Mass Air Flow MAF sensor or Air Intake Sensor AIS, depending on manufacture. It
does the same thing with different names).
Question: 1998 Mazda Miata mileage: 60,000. The car had a
new oxygen sensor installed at 50,000 miles. The check engine light came on after
that and the repair shop said everything was fine. After I disconnected the battery
to work on the radio (and reconnected it), the engine experienced major power loss
and hesitation, but the check engine light went out. The readings from the O2 sensor
and Mass Air Flow sensor are within spec, but if I unplug the MAP sensor, the engine
runs much better (although not perfect). I suspect that the MAP is bad and that
the computer was supplying a default value until disconnected the battery and now
that value is gone. I think that replacing the MAP will solve the problem but I'm
looking for some assurance that I'm on the right track before I lay out $190 from
the dealer. Thanks
Answer: From what you tell us, it would appear that the MAP
sensor (manifold absolute pressure) is causing your problems. Replacing it should
fix your problem. You can find that same part on eAutoPartStore.com for about $104.99
Question: 2001 Chevrolet 1500 mileage: 73,000. I have changed the plugs,
wires, throttle sensor and EGR valve. I also changed the oxygen sensor and had the
catalytic converter checked. The problem is that the truck loses a lot of power
when going up a hill and especially when I run the air conditioner. Could something
else need to be changed? No codes have turned up on the computer since the EGR code
and it was changed. Thanks!
Answer: It sounds like a fuel pump is starting to fail. It is common for
fuel pumps to fail at the mileage your car has on it. Replace fuel pump and fuel
strainer (attached to the bottom of the fuel pump) with new to repair problem.
Question: 1999 Honda Accord mileage: 119,000. The car is a Honda
Accord with Manual transmission. The problem is that when I accelerate with
the pedal about One quarter on the way down to full throttle it will start to hesitate.
Now this hesitation is like one of the cylinders is not firing. Which could
be possibly true. But this does not happen all of the time. Which is
becoming irritating. Sometimes it could do it when you startup and then for
a while it wont do it. I have replaced the spark plus and wires. Have
checked the fuel injectors with an ohm meter and they checked out o.k.
Because all of them have the same reading. This is the weirdest thing
that my dad has come a crossed too. He has been a mechanic for about twenty
years. I have heard that it could be an EGR Valve problem, but I think I checked
it out right and IT was fine. Another thing we checked was distributor cap
and the rotor. I don't know what else this could be. If you could be
of any help, it would be great. Thank You
Answer: Your problem sounds like a faulty distributor. Replace ignition
distributor with new to recheck system.
Question: 2003 Mercedes Benz, CLK 500 Coupe mileage: 42,000. Engine
runs wonderfully, and get awesome gas mileage (25-30 mpg), however, when accelerating,
the car will cut out for a few seconds, then suddenly take off very fast, all the
while my foot is holding the gas in the same position. The transmission and fuel
filter replaced about 20k miles ago.
Answer: Check the fuel pump pressure and the fuel pressure regulator.
Replace failed parts with new recheck system.
Question: 1999 Ford E150 mileage: 107,000. The vehicle lacks power,
especially when it is cold. It also has to downshift to maintain a set 65
mph with cruise on. This has gradually occurred over about 3 months.
I ran a self-test scanner on it, the response was code 225 "Knock sensor signal
not detected". I am not sure what that means. I recently put cap, rotor,
plugs, and wires on the van but this did not help. Thanks for any advice, Mark
Answer: Try replacing the fuel filter with new. Then check fuel system
pressure. The knock sensor code although active could not effect the performance
to that extent. The knock sensor is a problem but not thee problem.
Question: 2002 Chevrolet 1500 Z71 4x4 mileage: 80,000. It was running
rough very little power. Found low fuel pressure, so I replaced the fuel pump.
Now it runs great for approximately 5 minuets and quits. The engine turns
over but doesn't start. It will not restart until I wait approx. 30 minuets.
Then it starts, goes for a while then quits again. What is up with that.
Answer: If the fuel pump you installed was not OEM original equipment
manufacture, that is the problem. The fuel pressure it takes to run you vehicle
depends on 60 psi fuel pressure constant. Inexpensive fuel pumps are that way for
a reason, there are not as good and cannot hold pressure. Replace fuel pump with
OEM fuel pump to repair problem.
MORE: Engine low power questions
Repair Topics /
Vehicle Has Loss of Power-1
/ Vehicle Has Loss of Power-2
/ Vehicle Has Loss of Power-3
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