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.
