I noticed a metallic ticking sound during acceleration uphill last night. 98,000 plus miles, with no problems. The noise seems to stop when there is no load on the engine, going downhill or on a relatively flat road.

I have seen comments where people say this could be gasoline? I don't think that is the issue. It is a very metallic sound, doesn't seem to be an acceleration ping. I have also seen comments about valves or timing chain problems. Thoughts anyone?

Thanks all.

P.S. Glad to see you back GeorgiaHybrid.

 

You might need to reset the ECM computer but there are a couple of things that will cause this. A lower grade of gasoline than the car is used to seeing or bad spark plugs (have you replaced them yet?). What is happening is the engine timing is set too high and is causing "pinging" under load. It will be a very metallic sound and if you drive your car with an easy foot on the throttle, the ECM will learn your patterns and increase the timing curve.

Once that occurs, heavy acceleration or heavy load conditions (climbing hills) will cause the valves to ping or rattle. If you have changed your gas source lately, switch back. If you still have your original plugs, change them. If it is a learned driving habit by the ECM, reset it.

 

If it is only acceleration under load, I would agree with the pinging theory. If valve clearance it should be there most of the time.

One potential cause of pinging is carbon buildup on the cylinder and piston heads. You may want to try some fuel system cleaner to see what it does. One of the most effective ingredients of these cleaners is PEA or polyether amine. About the only product I can buy and has an MSDS that verifies it has it in significant quantities, is Gumout Regane Complete Fuel System Cleaner. See this MSDS. I would get a couple of bottles, and add it to two tanks of gas in a row. Burn nearly the whole tank before you fill up and add it to the second tank.

On a preventative basis you may want to consider using a Top Tier qualified gasoline. List of companies qualified are here. They have to prove their additives work in preventing fouling of the fuel system and cylinder heads. Costco also claim they use 5 times the minimum regulated EPA detergents in gasoline pumps designated with the Kirkland Clean Power logo. Probably not by coincidence that Shell V Power contains 5 (Roman numeral V) times the minimum required detergent also. However, at least in Canada V power is only available in premium grade, while Costco does it in their regular. Also Shell says there is nitrogen in their gas. Amine is made from nitrogen... Nothing new, other than the marketing spin. PEA has been around since the 80's and Chevron pioneered it. What differs is how much they put in.

As a last resort, you may want to try a higher octane gasoline. However, your Camry hybrid should run fine on regular.

Edit:

Most engines have ping detectors. They should detect pinging and retard timing to stop it. There is a possibility the detectors could be defective.

 

Metallic ticking sound, could be a weak CV joint. This is easy to prove. I go to a empty parking lot, football stadium of any paved area where you can safely turn a tight circle in a S shape.

I do my test at dusk or at night when their is less traffic and wind noise. In this safe area I stop and roll down both front windows or half way if their is any wind. You can do this with the engine warmed up and idling in drive. Turn the steering wheel to full lock make a few rounds to the left then turn it fully back to the right. Listen for any clicking or popping sounds. If you have a passenger with you, they can listen to the passenger side so either of you can tell which side may be causing the problem.

You can carefully do some slight acceleration while doing these turns. This would defiantly prove you CV's are ok.

CV joints do normally wear and will wear really fast if a CV boot is torn from a glancing rock from a front tire. These new boots on cars are thicker and resist being torn so easy compared to the boots used in the 80's and 90's.

Car appraisers/mechanics do the quick test which I don't recommend. They stop in a clear area, with the car in drive, they accelerate moderately while pumping the brake on and off at the same time, listening for clicks or popping sounds. To me this could abuse the 4 CV joints, but also may show up a defective inner CV where my test is for the outer's.

I will add I had a loud rumbling/vibration sound in my '94 Corolla when it had 150,000 on the clock. When accelerating at 45 to 60 the front doors would vibrate so bad you could barely talk over the noise. It would drive me crazy trying to climb any mountains even at 35 mph. I like to do my own work and read it could be the inner CV joints as they can cause this same accelerating vibration.

Being a rookie at CV's I took it to a axle shop here in town. The fellow had hurt his back and was retiring, closing down his business. He did put my car on a lift and showed me two small grease trails up on a metal cross brace that helps hold the engine transmission in place. He said this year Corolla I had was bad about throwing grease out of it's boot once it drys out. Replacements is the only answer and he named off some re-builders where he bought from. I bought used axles from one those suppliers that included all new CV's. After installing both axles myself the vibration was gone, but the axles seemed to cause a vibration when driving at 50 or 60. My thought was these were not spun balanced like the factory originals which after calling toyota parts found their's were rather expensive.

Lets hope you clicking sound is something else that's a easy fix.

 

I have been using BP, regular unleaded, gasoline and have recently (within the last month) used Techtron, Gumout with Regane fuel system cleaner, and some other fuel injection cleaners on a trip to VA. It doesn't look like they are listed on the top tier gasolines. I also changed my spark plugs recently.

I will try to check the CV joints as soon as I get a chance.

 

Top tier gasolines already contains a Techron type addative. That started with Chevron and they still add Techron to their gasolines. Other TT brands used a similar addative but uses a different name for it.

Your right, I don't see BP listed as a top tier gas. You would think such a large company would be listed.

Here is the list to look for a quality brand to use.

http://www.toptiergas.com/retailers.html

Use Gas Buddy below, add you zip just below the 'Search Gas Prices' then click Search to find a low price Top Tier station near you.

http://www.newmexicogasprices.com/GasPriceSearch.aspx

 

BP gas should not be a problem, they just refuse to pay for the "top tier" rating.... Ron, I should have mentioned that UWAdventurer has been here a while and I knew the type of gas he burns (the good stuff...) which eliminated that problem... The knock sensor "listens" for a resonance at 6400 hertz to pickup detonation in the combustion chamber. The light valve pinging we are talking about here will often escape that just enough to get by.

You can either reset the ECU using a bi-directional scan tool or by disconnecting the 12 volt battery for a few minutes. Once that is done, crank the engine and let it idle for a while to relearn its start state based upon the sensor data it is getting. This will reset the initial timing and the amount of fuel that is injected into the ports. A lean burn condition or timing too high will cause the symptoms you described but that should fix the problem.

I don't think a CV joint is the issue as they will normally sound off at low speeds while turning a tight circle. That noise is more of a "popping" sounds.

 

well, it's not high timing. it's advanced timing. for the record.
timing is 100% ECM controlled, nothing you can do there.
What you likely hear, and timing noise is very easy to spot - it sounds like a bunch of beetles crunching - is lifters tick. Or, you got rock stuck between treads.
As real preventative measure, pour can of Seafoam into crankcase, drive for about 500 miles, drain oil, refill with any cheap oil you can find in your weight, which is 5W20, run her for about 15 minutes, better off - drive around for 15 minutes, as engine shuts down and you can not idle it - drain THAT oil, and refill with good synth oil. I do Amsoil, but it's me.
As a result, you will have complete "natural" engine flush, and carbon deposits removed anywhere oil went during those 500 miles.
Be well, be happy.

 

BP is a very large company. If their gas met top tier standards, I'm sure they would get qualified.

Nothing you put in your oil will do anything for cylinder head deposits.

I recall somewhere in the Toyota information they say that under low rpm higher loads, it is normal/acceptable to have some slight pinging.

The quick test to determine if it is pinging is to put in an octane booster additive, or fill up with a high octane gasoline. If it still ticks during acceleration it is not octane pinging.

 

Ron, you need to remember where oil travels during engine operation. Cylinder head deposits ARE from oil. Oil goes everywhere, including cylinder walls. "Cylinder head deposits" is a very broad statement. The only area where you have no oil is combustion chamber, intake channels, and exhaust, and exhaust already has minute oil particles in it because it will get into cc-s from crankcase. Not a lot, but it will.
But it's idle conversation. Not such and idle topic is my years and years experience with Seafom. In petrol or in oil. Even better - though I wouldn't do it on a new car - even pouring it into CC-s and leaving overnight, to remove build ups on piston rings and restore compression.

PS. and not just from crankcase. Past valve stem seals also. Some makes, like MItsubishes, are "oil takers" because of poor seals design there. I know, we had 5 Mitsubishes - all take oil, all via stem seals.