1999 Explorer clacking sound

Engine running to lean ??? pinging

Replaced fuel filter @ the intervals it suppose to be replaced ???????????

Or 1 of the other 50 reasons that can cause a pinging engine

check engine light on ?????????

Is this the SOHC 4.0L engine? If so then it could be the timing chain tensioners. As I said in the post a few below there were extended warranties on this engine w.r.t. timing chain noise, etc., depending on your mileage. Check with a Ford dealer.

As for the starting issue this is usually caused by a dirty IAC, you may need to clean or replace it. See:

I ran into our local mechanic today, we only have the one in our small town, he corrected my use of clanking to pinging.

He did say exactly what you are saying and also asked if check engine light was on. No, the check engine light is not on. He said it could be the fuel filter but was unsure. We tried to duplicate it at the time but putting the unit in gear, stepping on the brake and putting it under load, but no pinging sound rose.

Seems to do it more when up to operating temperature when travelling but then only when going up a grade. From a dead stop, no ping.

Being in a farming district with alot of gravel roads, it does get very dusty so I plan to bring it in next week for servicing. Can't hurt.

Thanks

Allan

JohanB wrote:

Hi Al,

Thanks for the reply. As I said in a previous reply to another gentleman that I ran into our local mechanic today, he did say that the starting issue was related to the IAC, although he pointed out another component that was on the air cleaner intake hose and said this could be the cause.

Going to bring the unit in for service next week, it's due. Been pretty much trouble free since we bought it, other than replacing the front driver side hub at 100,00km.

Thanks

Allan

Al Williams wrote:

Not sure why, but the last 2 Fords I have owned, including the '97 Explorer I have had since new, have developed a knock running on regular gas fairly early in their lifespan. My dad's Lincoln, while he was still alive, did the same thing. Switch up one grade of gas from what you are using and the problem will go away. Over the years the octane rating of regular gas has dropped a bit at the pump.

Note, engine knock or pinging is the symptom for predetonation, which is when the fuel/air mix explodes before the piston is on a down stroke. Lower octane fuels burn faster, so additives to slow the burn rate are what makes higher octanes. Predetonation IS destructive to the engine and should not be allowed to continue.

While buying a higher octane gas may reduce/eliminate symptoms of pinging, wouldn't fixing the problem be less costly in the long run? Here, 89 octane runs about $.22/gallon more than 87 octane. After a while, that price difference would start to add up. I have a 97 Explorer that has ran just fine on 87 octane and now has 130K miles. In higher elevation states like Colorado, they sell 85 octane at the pumps. My owner's manual says to avoid using gas that isn't rated 87 octane, even at higher elevations.

To the original poster, have you checked your spark plugs and wires? Spark plug changes are at 100K mile intervals for the explorer engines.

We plan to service the vehicle this coming week, part of that will be to change the plugs and check the wires and change fuel filter amongst other obvious things. We bought the vehicle used at 103,000km a year and a half ago and have put 12,000km on it since. There was no ping when we bought it, this started at about 115,000, hardly noticeable but getting worse as the mileage progresses. Unlikely it had a spark plug change since new. Still have the original tires on it, time to change them however;-)

We don't plan to change fuel, book says to run regular.

Allan

Capta> While buying a higher octane gas may reduce/eliminate symptoms of pinging,