Engine pinging noise when shifting gears on highway

[Midnight]

Hello all! I am hearing a drastic engine pinging when shifting gears on the on ramp of a highway... Only when the transmission is lowering the RPM due to the transmission change.

Ideas? Only use premium fuel.... So it's not that.150K miles.

[RF Overlord]

Nowhere near enough info for an internet diagnosis.

Can you make a recording?

[Muddflapp]

I haven't driven enough miles on an OBD II car to experience it.
They say that when it starts to ping the computer takes care of it.

Too hot or too lean (which means too hot). Injectors dirty, fuel quality, EGR malfunction, computer timing based on bad info, air charge too warm, water leak, vacuum leak, thermostat, dirty or low oil that can't transfer out heat, plugs too hot, not enough ice in the air cleaner. I've heard about dirty air filters (but that would be rich but maybe the computer compensates with less fuel). I've heard theories about oil ping where oil gets past the rings or the valve guides (but that would seem to cool the combustion chamber, but it might interfere with the flame propagation).

I've had a 71 LTD 400-2V, 68 F-100 360-2V, 93 CV 4.6L-2V, and they all eventually get heat soaked and start pinging and burning oil on long idle (except the truck didn't burn oil). The 71 had the tops of the cylinders wallered / mushroomed out from piston slap? or picking the right engine speed between acceleration and deceleration (floating)? while not having enough top cylinder lubrication? I guess it's like multiple points of failure where any one of them can start the overheating. My 93 doesn't ping until the temperature gauge goes from N to O and finally up to the R in NORM. All the gauges use to ride on the O of norm, with not ping, but the temp gauge has been creeping up. Then it pings mostly between 2nd and 3rd and 3rd and OD. I just get out of the gas or hold it in the lower gear until the engine can pull quietly unless I'm stacking up traffic.

[martyo]

Can you datalog it?

[LANDY]

Sounds like not enough octane= too much timing. Should be fixible in the tune. Its been hot down there, what plugs are you running?

[Midnight]

Hey all! thanks for the responses. it doesnt do it all the time...

im running the Reinhart tune.. new autolite double platinum plugs. (just changed them) 93 octane BP, Chevron or Shell fuel (no cheap stuff)

Big 3 inch K&N cone filter to a (advertised on this website) intake.

i keep everything clean... MAF, PCV, idle control..

156K miles and counting... shes a good car.

no pinging or rap when starting up (timing chain) so that sounds good.

never been raced... (couple hard accels on the highway, perhaps i floored it) never been on a track. never will. (not worth my repaircosts)

I treat my MM well. like a princess really.. Showroom.

it doesnt ping all the time, perhaps on a hot, dry day it pings... wet cool days, nothing but power.

Fuel pump not providing acceptable rate? ill find a guy with a gauge.

thanks, if anymore ideas, let me know.

[RacerX]

new autolite double platinum plugs. (just changed them)
How was your car before the last thing you changed? ;)

[Comin' in Hot]

sounds stupid but i had a belt tensioner make that noise

[lifespeed]

disconnect the battery for 10 minutes to make the computer forget any "learned" timing adjustments. Also double-check the plug heat range is correct.

[JohnE]

You need to put proper plugs in those double platinum plugs are likely your issue. Either use Motorcraft AWSFA-22C or a good aftermarket one like brisk from a performance shop.

Or you could just put the factory tune back in.



John

[babbage]

You need to put proper plugs in those double platinum plugs are likely your issue. Either use Motorcraft AWSFA-22C or a good aftermarket one like brisk from a performance shop.

Or you could just put the factory tune back in.



John

You are running a Reinhart Tune, he recommends running 1 colder plugs with his tune. NGK-TR6 for example. As JohnE and RacerX already said
it's the PLUGS.

Side Note: Ever change the anti-freeze in 150K miles?

[MOTOWN]

I had the worst luck with those Autolite plantinum plugs, nothing but junk imo.

[RF Overlord]

Either use Motorcraft AWSFA-22C That's an old number. Motorcraft updated their spark-plug numbering scheme and the new number is SP-505, one step colder than the stock SP-493.