mercury marquis pinging noise from engine?

Question

engine pings about 45mph under light load or going up small hill. ping will stop if i step down and it downshifts to lower gear. have tried additive: still pings. ping will stop if i use higher octane gas, but dont want to do this all the time. was told it may be air flow sensor. is there anything i can do to clean the sensor or otherwise fix this problem. dont want to take to shop and have them throw parts at the problem. thanks for any help.

Answer 1

If it's around a '95-ish, it's a common concern. Try removing the "SPOUT" connector in the engine compartment. It's two wires that run into a blank connector, secured to the left side inner fender close to the power steering fluid reservoir. Also, if it is a '95 or older, you should have the EGR passages cleaned of all the carbon that builds up. Whoever told you it may be a MAF sensor is on the right track. Hope this helps. Good luck. Note: Those other mechanics coming on here to advise to you reset your timing are incorrect. On your particular vehicle, there is no distributor, and therefore ignition timing is NOT adjustable. Your vehicle is equipped with eight individual coilpacks that sit on top of each spark plug. The MAF sensor can be cleaned, but ONLY with the RIGHT product!!!

Answer 2

It has everything to do with what year the car is, and which engine it is, to give you a correct answer. There seems to be a lot of speculation on here as to what the problem is, and some of it is right in line with what to look for. How many miles is on the vehicle? If it has a timing chain or belt also has a factor in this. I have worked on cars for over 40 years, and I can tell you; this is not something anyone can answer without knowing this other information!! If you don't want a shop throwing parts at it, you can just throw parts at it yourself, and spend more than what you would if you just took it to a shop to begin with. You say you want to clean a sensor or otherwise fix the problem, and you get 25 different answers on here, and I have to believe you are no futher ahead than you were when you started. I can tell you this and be honest; the pinging you hear is really bad for your engine, and is doing damage to the pistons. A good shop will not throw parts at it like you think. All you got to do is ask them what it will cost to fix it!! We would all agree that it sounds like a timing problem, and setting the timing would resolve the problem. I have had to remove a lot of stuff from the front of the engine (on Fords) and use a long bar to drive the distributor out, because it would not budge any other way. Pretty costly to have this done, but you may find that you really do need a mechanic. Sometimes setting the timing turns into a nightmare. Right now, some of the mechanics on here are scratching their heads, and rethinking their answers, as they will recall what I'm talking about. This is a problem that I have only saw on a ford. I would think it is caused by the timing chain getting old and stretched, thus needing the timing reset to spec's. Try adding this information and asking the question again, and you will come up with the right answer. My answer would be; take it to a reputable mechanic and find out what the problem is before it ruins a piston. Good Luck!!

Answer 3

About some of the earlier answers:

*No V8 engines have timing belts, the torque a V8 makes destroy
a timing belt. Not a very informed suggestion :|
*No Grand Marquis/Crown Victorias have been made with distributors in over ten years so HOW are you going to adjust the timing unless you have some way to re-program the computer. (No disrespect intended but you do not sound like you are about to reprogram the computer.)

You didn't specify what year your car is. You went to a higher grade of gas and the "ping" went away. If your piston compression is greater than 9.5:1 compression ratio you NEED high octane (premium) gas.

There's no way around it. That "pinging" is your pistons firing before they should. Lower octane grades are more explosive and when you combine that with a higher compression pistons it is much easier for combustion to happen when you do not want it to. So while your pistons are trying to "compress" the explosion that happens is trying to "expand" which will eventually RUIN YOUR ENGINE.

It's kind of like you swinging your arm (representing the piston) and Shaq O'neal (representing the early combustion) coming along and violently slapping your arm in the other direction. Do you want that happening to your pistons 350 a minute while you are on the freeway?

I have 2 cars now that require premium gas and my last 4 cars required it. Initially, I didn't know my Acura needed it but that was just ignorant to assume that it didn't. How else are you going to get 120 horsepower out of a stock 1.6 liter engine unless you have high compression pistons? I upgraded to premium, pings went away immediately. My 92 SHO and 97 SHO both require premium and yeah, it cost A GRIP to keep gas in both of them but they will be destroyed if I don't.

So you need to decide what is cheaper.

Answer 4

First have a dealer to clean the EGR ports, then remove the octane shorting bar, a 2 wire connector near the air box and power steering res. it has a green and grey wire going to it. Remove the grey plug and just leave it out.

Answer 5

Could be the MAF sensor, or something with the egr valve isn't correct.
Valve noise is caused by
engine overheating
lean mixture
cheap fuel
lack of egr flow
too much spark advance

Answer 6

first thing, put a code tester on it and see if you're getting any active or any stored trouble codes that could help lead you to the problem.
Engines these days run so lean that it seems most will ping eventually.

Answer 7

i own a repair shop,and what its doing can be cured by re-setting the timing on it,id bet it has never been set before,and slow timing will make it ping when in a bind,id take it and have it checked,and it could be the flow sensor like was mentioned ,but i been at this for 36 yrs,.and i have repaired a lot of those just by re-setting the timing back to where it should be set at,good luck i hope this help,s.

Answer 8

Dodge man is right on.set the timing.