Engine ping

[Hauser717]

120,000 miles on the Merc and I'm starting to get some engine ping. Usually when going uphill or light acceleration. Sounds fine at idle/cruise/WOT. My only engine mods are a JLT cold-air and the SCT tune.

Any suggestions on what I need to do?

[fastblackmerc]

120,000 miles on the Merc and I'm starting to get some engine ping. Usually when going uphill or light acceleration. Sounds fine at idle/cruise/WOT. My only engine mods are a JLT cold-air and the SCT tune.

Any suggestions on what I need to do?

What octane gas are you using?

[Hauser717]

She only feeds on Premium.

[fastblackmerc]

Last time plugs were changed, MAF cleaned, air filter cleaned?

[Hauser717]

Plugs at 100k. Air filter about 6 weeks ago. Checked it this morning and it's still red.

MAF... Dunno that it ever has been cleaned.

[SpartaPerformance]

Sounds like you may have some carbon build up at that mileage.

[SID210SA]

Does it sound like a ping pong ball rattling around? Thats what I have, but only when its hot outside...and only going up a long hill....I have no idea what it is.

[sailsmen]

Try a bottle of Lucas Fuel Treatment.

[fastblackmerc]

Try a bottle of Lucas Fuel Treatment.

That ^^ and Seafom the engine.

[burt ragio]

At what rpm does the ping happen maybe 2300 ? Close plug gap to least range setting. As mentioned clean maf, seafoam engine, do a Lucas treatment in gas tank.

[vtwoodsman]

Carbon build up on the piston face retains combustion temps and causes pre-ignition.
Use fuel system cleaner over several tank fill ups.

[babbage]

At what rpm does the ping happen maybe 2300 ? Close plug gap to least range setting. As mentioned clean maf, seafoam engine, do a Lucas treatment in gas tank.

Agree, also look at getting a cooling system flush if you've never done that. Is the radiator clean, not clogged with debris?

[BODYMAN]

Try a bottle of Lucas Fuel Treatment.

+1 on that & also being in KC do U get 91 or 93? What is youre sct tuned for 91 -93? Just a thought but does sound kinda like carbon depositsCleaning a maf is simple probably has nothing to do with the problem but if never had get U a can of MAF cleaner and spray it when removed it's a breeze

[slickster]

Spark knock is bad for a motor. Deal with it very soon

[FordNut]

Sounds like carbon buildup to me. I think they used something from Berryman on the wife's car when it did that.

[burt ragio]

I've read a lot about Seafoam it seems to be the overwhelming favorite. Thing is, another board I'm a member of is staunchly Berryman's territory, so I decided to compare for myself.

I've found the Berrymans exhibits far less 'smoke' when utilized in the same manner as the seafoam for cleaning the intake tract. I wondered why, so I got hold of the MSDS sheets for each. Turns out the Berrymans utilizes more of the light hydrocarbon solvents than the Seafoam, tolulene mostly, and that makes it a better solvent and cleaner burning. It also evaporates more quickly because of this, but I just don't see that as a downside since you either burn it in your intake or dump it into your fuel tank and dilute it.

[Captain Dynball]

When cleaning the MAF do not directly touch it when anything unless needed. If you do need to touch it use a Q-Tip and be very light with your touch. Get some MAF Cleaner or Electric connector cleaner for the MAF element...should get it shiny again.

[mgmsleeper]

I've known seafoam to be good but also bad. Yes it'll clean your motor but at the same time itll reveal any issue that the motor has that may have not been present at the time.

My 95 SS had a seafoam treatment one afternoon after getting an oil change and mechanic saying car is strong as an ox and it uncovered I needed a new motor AFTER the fact of driving it from Baltimore. And running around town. After all the carbon and whatever else was gone the problems occurred. So I guess it's all about how good of shape you're in BEFORE the seafoam

[Hauser717]

Thanks for all the input! I'll head to Autozone at lunch and pick up the Lucas Fuel Treatment, a bottle of Seafoam and some MAF cleaner.

[RacerX]

As was said, carbon buildup. The carbon isn't flat or uniform at a microscopic level and the edges/points of carbon can start to glow like a diesel glow plug at heavy loads causing preignition. I'm not too thrilled with Seafoam after some tests I did.

[Phrog_gunner]

You can also do the "BG" fuel system cleaning. It does the entire fuel and air intake system, and most dealerships offer it. Lots of other mechanics have it as well.

[JoeBoomz]

Failing all of the above suggestions, it may be time to change the o2 sensors. If they are not reporting the air fuel mixture properly the car might lean out and this would also cause spark knock.