2000 Camry tick tap ping only when warm

[Plaz]

My 5S-FE 2.2 2000 Camry engine make a lot of noise once it's warmed up. I've seen this noise described as ticking, pinging, and one colorful descriping that matched pretty well as "dropping marbles in a metal pan".

What makes this a bit unusual it that when the car is cold and first started, it is silent. Only the clean familiar whine of a healthy Toyota engine for the first 10-15 minutes. I can rev the engine fast or slowly, no noise. There is not even a hint of tapping that some describe at cold startup when oil needs a few seconds to circulate. I've also noticed the gas milage has dropped off, going from about 30-31 down to 26-27 in the past 18-24 months.

I take good care of it with regular server and even changing oil more frequently than required. Durning one service visit I had them check for sludge. They told me it probably wasn't necessary, I said check anyway, and they said it was clean.

This ping, tap, tick is heard throughout my normal rpm band (700-3200rpm). It's intensity will rise and fall as the load changes will throttle, and hills. It will remain pretty steady if the load and rpms remain so.

At first I was leaning towards valve clearence issues. After more reading on ToyotaNation, I can't find an exact match, but I'm beginning to wonder if my issue might be more related to a pre-ignition problem due to timing or sensors (O2 possibly) since it runs like a charm for the first 15 minutes before it reaches normal operating temperature.

My timing belt and water pump were changed about 15,000 miles ago.
I have about 140,000 miles on it.
I had the plugs, wires and air filter change 7-8000 miles ago.
Oil at about 1500 miles and it was clean.
The Transmission was flushed (not just changed) about 22-24,000 miles ago
I've owned the care since 2001 and bought it with about 25,000 miles on it.

There is no engine light, but I am off to get the codes read in a few minutes to see if there are clues there. I'll post the results when I return.

Thanks for any feedback. I want to narrow this down so I might repair it myself or at least know what I'm talking about if I have to take it in for service. I don't want to be told I need an expensive valve job, engine rebuild/replacement if all I need is an O2 or knock sensor replaced.

[Plaz]

There is no engine light, but I am off to get the codes read in a few minutes to see if there are clues there. I'll post the results when I return.

Well no codes were expected without an engine light, and none were found.

[Punks_Not_Dead5]

2000 Camry = Gen 4, not Gen 5 or Gen 6

[Plaz]

Originally Posted by Punks_Not_Dead5

2000 Camry = Gen 4, not Gen 5 or Gen 6

Sorry, any way for moderators to move it to the proper thread?

[Plaz]

BTW, when I last had the timing belt replaced, I had the water pump replaced too. I was told that the noise was the water pump and it would be elimintated. It wasn't of course.

Plaz

[BlueFusion6851]

Have you tried changing the grade of gasoline you put in to see if that helps? Have you tried seafoaming through the brake booster line?

[Tom 2000]

Sounds like you have carbon deposits in your combustion chamber. I had the same issue with my 1988 and my 2000 when it was newer.

The carbon deposit is increasing the compression ratio in your engine and the air/fuel mixture is pre-igniting, hence the sound you get.

There are some things you can do.

1) Fill it with Super Unleaded. This is a temporary solution as the higher octane fuel will reduce the tendency to pre-ignite. Soon as you fill it with regular, the sound will come back.

2) Use Fuel Injector/Combustion Chamber Cleaner. Chevron Makes a Good Fuel Systems Cleaner forumlated to clean combustion chamber deposits. I've used it on my car with good results. The link has some details. You can pick up the fuel system cleaner at most auto parts stores and Chevron gas stations.



http://www.chevron.com/products/ourf...tives/tcp.aspx

Needless to say, 2) is what I recommend. Use it, and after 1 tankful, it should get better.

[lenjack]

Yes...preignition = spark knock. It's an octane problem.

[Plaz]

Thanks for the feedback all. I will definitely try your suggestions starting with a tank full of premium the next time I fill up. If I see (hear) a signifigant improvement, then I'll move on to the other deposite cleaning solutions. I actually bought a bottle of seafoam a couple of months ago, but hadn't used it yet. When the Toyota tech told me it might be lifter adjustments, I thought "seafoam won't help that".

I've read that seafoam will clean the topend, does it do the job in the cylinder too?

I'll post updates as I work on this.

[BlueFusion6851]

Yes, if used through the brake booster, it cleans carbon deposits out of the intake, cleans the injector, and carbon deposits out of the intake and exhaust valves.

If used in crankcase, it cleans some sludge deposits out of oil passageways

and last but not least

If used in gas tank it helps the gas from breaking down over long periods of time.

[Plaz]

I've been running 93 octane this week and the noise has improved, but not completely disappeared. My performance is noticeable better too.

Where before the noise was constant and non-stop once the engine reached normal temperature, now the tapping seems to come an go depending on my throttle and acceleration/deceleration. Also the noise seems to be only half as intense as it was when running on the regular 87 octane.

If I can find a way to NOT irritate the neighbors with the expected large cloud of exhaust smoke, I'll attempt to use the seafoam this week end and see how things change or improve further.

Plaz

[Plaz]

Here's an update on my issue....

I've been running high octane the last couple of tanks and that helped some a little. I also sea foamed through the brake booster and that also improved the noise even more. It also seems to run a little smoother with slightly better throttle response after the sea foam. Over all the noise is better, but still not gone. The noise is less and happens over a slighly different rpm range than before. But still basically the same symptom... quite when cold, tapping when hot. It's definitly improved though.

I also found another problem that may or may not be related to this one. I have a split hose at the intake manifold causing the air filter to be bypassed. The hose was split on the backside, so it wasn't visible. It wasn't until I had grabbed it and felt my finger go through the hose on the backside that I relized it was broken. I can't identify the part or hose to get a replacement. I've posted a new thread about it here..

http://www.toyotanation.com/forum/sh...58#post2575858

Could this problem be messing with the mixture or computer to cause my noise and drop in MPG/performance?

Plaz

[Eye8Pussies]

^ depending on where the split is, yes. if it's before the MAF sensor, then it won't make a difference, but if it's after the MAF sensor (between the MAF and the throttlebody) then the engine will be taking in more air than the MAF is telling it that it is

also, don't forget to change your fuel filter. not a bad idea if the problem is apparently related to pinging

[DFBonnett]

You might also check the EGR system. If it is obstructed to some degree you would get elevated combustion chamber temperatures which could produce that ping you noted. Just a guess but worth mentioning as a possibility.

[Plaz]

Bit of an update:

Though the diagnostics wasn't showing and trouble code, I went ahead an replaced the knock sensor on the chance it might be going bad and confusing the timing. With out too much suprise, it made little or no difference in the ping. Though after replacing the knock sensor, the performace seems a little better when accelerating.

This morning a new thought occured though..... Around the same time I first notices pinging, I had the Camry in for service to replace the water pump, timing belt and oil change. Just what if the new belt was put in and was a notch or tooth off from where it should be? I did some searching and though I didn't find camry specific references, there were other people who had ping problems after a timing belt change. Could that be the root of my problem?

Can any one tell me the easiest way I can check to confirm that my belt is aligned and installed properly? Maybe the new belt is just off by a bit.

Plaz