2002 Toyota Corolla mileage: 40,000. When I
bought this car 2 years ago, I noticed that
when the car had been run for 15 or so
minutes at regular operating temperature,
there would be a rattling sound, like timing
being off, under heavy acceleration. I've
had it in the shop several times, and gone
through a couple of entire tune-up component
changes, as well as had the timing checked
each time. Everything was said to be fine. I
tried a higher octane gas, fuel injector
cleaner, almost anything suggested, and
still the timing pinging continued, but over
time, has worsened. This spring, as warmer
weather has returned, the pinging has
worsened to the place that, once the car
reaches normal operating temperature, I
cannot accelerate without bad timing
pinging. I've frustrated my mechanic who's
even advanced (I think) my timing to get me
off his back. It doesn't seem to matter. Am
I dealing with an engine that has run its
course and needs to be changed?
Answer:
A non-functioning EGR valve is probably causing your ping
problem. Verify that the valve opens properly and the
ports under the valve are clear. Next recheck the timing
belt, if installed incorrectly it will cause the engine
to ping and have low power.
Question: 2004 Ford T-Bird mileage:
38,000. Dear Bob and Ken, I bought my T-Bird used with
7,000 miles about 6 months ago. Now it has 38,000 miles
on it. The car pings when you get on it hard. It
also only gets about 18 mpg overall. I checked over the
plugs and put a professional 3-part injector cleaner in
it along with a fuel filter. The car is still no better.
Also the car in 1st gear tachs up to 4500 rpm and shifts
and drops to 2900 rpm, which seems to cause the pinging.
Is this normal? What can I do to achieve good gas
mileage with using expensive premium gas to stop the
pinging?
Answer: This is difficult
because the computer can't detect a 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: 2001 Jeep Grand Cherokee
mileage: 75,000. I read about the "knock sensor" that
you have alluded to in answers to other questions. Does
my model have one of these? I am experiencing extreme
knocking when I use anything but premium gas! This has
been going on for a long time now, but has really only
hit home recently with the rise in gas prices. Would the
knock sensor be the only thing that could explain this
problem, because I have asked my mechanic before about
it and they didn't mention this?
Answer: Your car may not be
equipped with a knock sensor. Check the EGR valve
operation. If it is not functioning properly, it can
cause engine pinging.
Question: 2002 Ford Windstar
mileage: 48,000. Fairly frequent ping while under mild
to moderate acceleration between 1300 and 2200 Rpms.
Ford shop has done several adjustments in accordance to
Ford Tech Service bulletins. Have tried mid and premium
grade gas. All changes have made no improvement. From
the questions posted, this seems to be a common problem
with a lot of newer vehicles.
Suggestions/Recommendations? Besides, trading for a
different vehicle? Thanks.
Answer: Some Ford engines are
not equipped with knock sensors. Yours may be one of
them. Located in the wiring loom, close to the ECM, is a
"octain adjustment bar" that when removed retards the
timing 4 degrees. This should correct your pinging
problem.
Question: 2001 Ford E150 Van
mileage: 66,000. I've got a Ford Van - Australian car
but same set up as a F150 or similar Ford E150. The van
has started to ping very badly with even moderate
acceleration. Sparks seem fine, timing is spot on - van
could be running better, but it doesn't seem to be the
problem. A few friends believe it is the fuel filter. Is
there a particular part of the ignition, which would be
causing the majority of the problem, or something, which
I can replace myself? If not I'll have to get it
overhauled, but that's pricey. Thanks.
Answer: Your engine is
equipped with an EGR valve, check operation to replace
as needed.
Question: 2001 Mitsubishi Eclipse
mileage: 55,335. My eclipse pings when I accelerate, and
especially when I climb hills. It also tends to do this
when my rpm's drop after I shift the transmission
switches to a higher gear such as third or fourth. I've
already checked the ignition timing, and it's correct,
I've replaced my plugs and wires. My cylinder head was
just replaced in 1999. What are some of the causes of
this problem or can you give me any advice to aid me
with this problem? Also, as I replaced my spark plugs, I
noticed that they had carbon deposits on them thus
telling me that my car is delivering more fuel than
oxygen into the combustion chamber. The inside of my
exhaust is black and filled with carbon as well. My dad
is a mechanic, and he believes all this is caused by my
valve lash adjusters that tick like crazy. When we
replaced my cylinder head, I couldn't afford to buy new
adjusters, so we put the old ones back in. Could the
adjusters be the reason for any of my problems?
Answer: If the timing belt has
been installed wrong "off a tooth or two" it will cause
pinging poor mileage, low power and noisy cam followers.
Disassemble to recheck and adjust as needed.
Question:
2002 BMW 745i
mileage: 55,000. Had slight knocking or pinging
since new. Thought it might be oxygenated gas.
Tried mixing higher than 87 octane. Some
improvement. Didn’t want BMW service to fool with
new engine. Hoped it would resolve spontaneously.
Finally took to service, they said that computer was set
to 89 octane. and reset to 87. Got
back from service.... no change. Don’t know if
will improve. Know nothing about cars. Hate
this problem and am anal about it. Thoughts?
Answer: The pinging may be due to a
faulty knock sensor or possibly an EGR valve that is
malfunctioning.
Question:
2003 Honda Accord mileage: 44,000. I have a Honda
Accord 5-speed. I have had trouble with the engine
pinging since day 1. I have had the computer
checked constantly, the scan and nothing helps. It
pings a lot under load such as going up a hill or
accelerating quickly. I have had a couple
different mechanics look at it, but they couldn't find a
problem. Any suggestions you can give me are
greatly appreciated. Thank you for your time.
Answer:
Check the EGR valve to be sure it is opening. The
function of the valve is to stop engine pinging at the
mid rpm range.
Question:
2002 Dodge Dakota mileage: 49,000. You have
touched on the subject, but I wonder if you might help
me. I have low rpm spark plug knock in my Dakota 4x4.
The dealer says I need higher-octane fuel. In your
FAQ archive, I noticed that you told another Dakota
owner to check the EGR valve. Is 96 octane high
enough, or do I need an additive (102 boost, etc)?
This pinging is making me crazy. Thanks!
Answer: The EGR valve can cause the pinging
but also check the knock sensor. If the knock
sensor is functioning properly, it detects the pinging
and retards the timing.
