CJW_TL07

I own my 05 TL, live in MD, always use 91-93 octane gas from the major suppliers and get on average 27 MPG. You can guess my driving style. However on 3 different occasions, winter, spring and just last week (70C) I've floored the gas pedal and heard a loud pop/bang.

Naturally I eased up on the pedal, the engine after its momentary hiccup, continued pulling as normal. It doesn't always happen either.

My other observation is frequent, low but discernable valve chatter when gentle gas applied or incline encountered.

What do people think is the underlying problem? Engine Management Processor, VTEC or O2 sensor problem? Thanks.

01tl4tl

How many miles do you have? What brands of gas do you run?
are they Tier 1 level- 76 Chevron Texaco etc, they use different stuff in it that helps keep things cleaner- nothing keeps the engine spotless, so it does need some extra care-
we have hi compression engines after all!

If it were my car, and based on recent reading of gen3 Throttle Body problems and replacements, I would read the gen3 DIY on Seafoam and do a cleaning with the gas tank method, and the intake vac port to clean buildup from the valves and piston tops, the gas tank method gets the fuel injectors clean

After that and a few days driving to burn off the loosened crud, get the codes read at most parts stores for free.
Report back here with any the car is giving - the codes are ~clues~ not diagnosis

Normal operation of the engine causes bad stuff to build up on important parts-
carbon crust on the piston top will cause detonation- premature ignition of the gas/air mix- results can be the noises you describe
Lets hope its the 15 dollar cleaning fix not the 300 dollar parts replacement fix!~

Will Y.

It sounds like you've covered the variables, so try adjusting the valves. Valve adjusts are an "as needed" on the TL and not part of the normal maintenance minder/schedule like most cars with adjustable valves.

See if there is still a problem after the valves are adjusted.

Welcome to AZ, and G/L!

CJW_TL07

My car has 36,000, so I'll also check with dealer as I've got warranty left.

Btw, what are your thoughts on:
1) periodically accelerating hard, to keep deposits down?
2) Is there an advantage between buying premium 93 gas at a generic station versus same cost 89 at say an Exxon, Chevron etc. which provides assurances for cleaning additives? I know the best answer is Exxon and 93, but depending on location that means $4.40...

Thanks Gents for the quick info, looking into these remedies.

01tl4tl

there is a warning label on the gas cap door 91 octane minimum for a reason
Yes you can get away with 89 but its not good for the overall health of the engine!
Hi compression engines need the proper gas to prevent detonation- thats bad!!!

Just flooring it wont clean things out- you can add a cleaner to the gas tank or use seafoam- wynns- or honda fuel induction cleaning system to get everything really clean
What comes from gas station is a maitenance low dose- not a super duty cleaning.
Chevron says that regular use for 5000 miles will slowly clean everything.
Some of us like to get it done now, and be running better today

PhilB81

Alright I tried the Key Pause method, I actually waited till my seatbelt warning stoped beeping and then I started the car. The pinging didn't completly go away, it was still present at around 3700 rpm (exterior temp 81F according to the thermometer in the car). This result was much better than yesterday when I my valve chatter was absolutely none-stop, and in Vtec was the worse. I'll continue playing with this.

I hate cars

Popping back through the intake is a symptom of running lean. So is pinging.

More octane will help the pinging but won't change the popping.

Running lean can be fuel pump/injectors/02 sensors/fuel filter. Get the car on a scanner and see what it looks like.