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I have a 1998 Ford Expedition XLT with 2WD and the small V-8 engine, it has 97,000 miles on it. I am experiencing engine knock.
When I start the SUV there is a loud pinging noise as if someone is hitting the engine with a hammer. This lasts only a few seconds then stops as I drive a few hundred yards. It does not happen every time I start the SUV.
I have taken it to the Ford dealership several times about this problem and they put in a gas additive which seems to take care of the problem for a while but then it returned (after about two tanks of gas). The engine will also rattle when I accelerate. If I use high octane gas the probem seems to go away or does not happen as often. I have had two ignition coils replaced already, which caused a similar noise, however this time the Ford people say that all the ignition coils are fine. The pinging noise also seems independent of the weather, but will occur more often upon starting if the car has been idle for a long time.
Meaning overnight or sitting in the parking lot all day at work.
Answer -
Jeff first thing the morning knock will go away believe it or not with a ford oil filter i believe it is an 820 # what kind of gas are you using and i hope you don't tell me shell we have been having a lot of problems with this gas. is the ck eng light on if so what are the codes?
Follow up-
Ragu I always have the Ford dealership change the oil and use the Ford oil filter. The gas I am using usually is not shell, but usually is Wal-Mart brand or Hess. When I use the high octance gas the knock goes away. I had the oil changed last week and filled up with Wal-Mart high test and haven't had the knock since. Also the check engine light has not come on.
AnswerJeff you need to have the comp. ck to see if the timing is advancing to soon. which will cause a knock also a bad 02 sensor, egr carbon build up,a vacuum leak,coolant temp to high this are things you need to ck out .you could do this with a scanner if you have access to one. do this first and let me know what the readings are .
