98 Camry Engine Revs Loud When It Starts

[numberforty1]

Noticed for about a week now, the engine sounds like it is working noticeably harder right after the starter turns over, and it stays that way until I put the car in gear. It also sounds like it is working harder when I accelerate in 1st and 2nd gear. Once I get the engine warm and over 30mph or so it is not so noticeable anymore. I've read everything on this, from exhaust leak to timing belt (the timing belt was replaced about 30K ago).

When it starts the engine seems to idle at about 1500-1700, then drop to about 1000 when I put it in gear. I'm not sure but isn't 1500 a bit high for idle?

Anyone had direct experience with this?

98 Camry V6 with 193K

Thank you!

[Yuko]

The idle speed sound correct for a cold engine. This is known as "fast idle"; a function to get the engine warm up quicker and into a closed loop for emission reason. Not sure about why it's working harder. A problem with the IACV usually cause a lower idle speed.

[projektvertx]

That sounds normal for idle speeds to me. 1000 rpm when in gear right after starting? That's normal As for the "working harder", do you mean it won't shift out of second until pretty late? I'm pretty sure that's normal open loop behavior

I'll continue down the road of inquiry nevertheless What is the remaining maintenance schedule of the car?

[numberforty1]

Originally Posted by projektvertx

That sounds normal for idle speeds to me. 1000 rpm when in gear right after starting? That's normal As for the "working harder", do you mean it won't shift out of second until pretty late? I'm pretty sure that's normal open loop behavior

I'll continue down the road of inquiry nevertheless What is the remaining maintenance schedule of the car?

Thanks...the details of closed/open loop function are too complicated for me, so I don't know how that plays into it, but I suppose I could have a bad sensor or something that is messing up the transition between the two.

As to your questions - when I say "working harder" I simply mean that it sounds like the engine is at a higher RPM than usual, as if I am giving it gas, but after having checked it the RPMs are normal, and of course I'm not giving it any gas. This is all before I even put it in gear. I have had this car 13 years, so I know the difference in sound when I hear it.

Not sure what you mean by "remaining maintenance schedule", but if you mean what maintenance it currently requires, it is pretty up to date. As I said, the timing belt (and spark plugs) was replaced about 30K ago, just had the transmission flushed 8 months ago, coolant changed just 3 months ago, changed oil about 1500 miles back. It still has the old water pump though, and I've been thinking of having the fuel system cleaned.

My parents have the same car, and they just had to repair a hole in the exhaust pipe, so I was wondering if I had the same problem, but it seems to me that the issue is with the engine itself, not just the exhaust. I'm inclined to believe there is an electronic system error telling the engine something wrong, but of course what would I know.

My engine light is always on, but I've had the diagnostic run on it a million times, including recently, and it always comes back as an emissions sensor issue which I've always been told does not affect the operation of the engine.

Thanks for the help! Interested to hear what you think.

[projektvertx]

Originally Posted by numberforty1

Thanks...the details of closed/open loop function are too complicated for me, so I don't know how that plays into it, but I suppose I could have a bad sensor or something that is messing up the transition between the two.

As to your questions - when I say "working harder" I simply mean that it sounds like the engine is at a higher RPM than usual, as if I am giving it gas, but after having checked it the RPMs are normal, and of course I'm not giving it any gas. This is all before I even put it in gear. I have had this car 13 years, so I know the difference in sound when I hear it.

Not sure what you mean by "remaining maintenance schedule", but if you mean what maintenance it currently requires, it is pretty up to date. As I said, the timing belt (and spark plugs) was replaced about 30K ago, just had the transmission flushed 8 months ago, coolant changed just 3 months ago, changed oil about 1500 miles back. It still has the old water pump though, and I've been thinking of having the fuel system cleaned.

My parents have the same car, and they just had to repair a hole in the exhaust pipe, so I was wondering if I had the same problem, but it seems to me that the issue is with the engine itself, not just the exhaust. I'm inclined to believe there is an electronic system error telling the engine something wrong, but of course what would I know.

My engine light is always on, but I've had the diagnostic run on it a million times, including recently, and it always comes back as an emissions sensor issue which I've always been told does not affect the operation of the engine.

Thanks for the help! Interested to hear what you think.

If your check engine light is on, I would drop by Autozone, they can read the code for free for you I'd look into that and report back once you have a code

[oopssorryy]

Definitely get the check engine light checked out, and I would get your exhaust looked at. If your RPM's are staying stable, but the noise is up that's what I'd look to. Does it feel as if you've lost power or the engine is bogging down?

[numberforty1]

Originally Posted by oopssorryy

Definitely get the check engine light checked out, and I would get your exhaust looked at. If your RPM's are staying stable, but the noise is up that's what I'd look to. Does it feel as if you've lost power or the engine is bogging down?

Haven't lost any noticeable power, drives pretty well considering its age.

[numberforty1]

Originally Posted by projektvertx

If your check engine light is on, I would drop by Autozone, they can read the code for free for you I'd look into that and report back once you have a code

I have the code at home, I'll post it here later, and try to drop by Autozone to see if it has changed in the past couple months.

[numberforty1]

Originally Posted by projektvertx

If your check engine light is on, I would drop by Autozone, they can read the code for free for you I'd look into that and report back once you have a code

Code is PO446 - Evap Vent Solenoid Problem - Helpful at all?

[projektvertx]

Originally Posted by numberforty1

Code is PO446 - Evap Vent Solenoid Problem - Helpful at all?

So I did a little bit of reading up on that code, since I'm unfamiliar with it and here is what I was able to find out. It can be one of two things, the gas tank cap, or the the charcoal canister VSV. I read this up on how to test the VSV:

I have seen hundreds of P0446 codes on Camry like yours. 90% of the time it is caused by a bad tank by-pass valve (VSV) on the charcoal canister. You can check the valve by removing it and applying power to one pin and ground to the other. The valve should click... you'll hear it and feel it. Sometimes the valve sticks intermittently, and you may not experience it when testing it.

The P0446 can also be caused by a bad Canister Control Valve located on the air filter housing. You can test it the same way. This valve turns on and kind of clicks rapidly when power and ground are applied.

There can also be a leak in the evaporative system. This is very difficult to find, and you'd need special equiptment to test for a leak. Your best bet is the dealer. They see the P0446 everyday, and they'll be able to diagnose the problem relatively easily. Usually they charge 1 hour labor to diagnose it. From there you can repair it yourself if you want.
The EGR valve will NOT cause the P0446 code. The EGR system have a few codes specific to it, like P0401. Your problem is in the Evap. Emission System.

Since I'm unfamiliar with this particular code, I'll ask Mister_Perkins to chime in on this one

[numberforty1]

Originally Posted by projektvertx

So I did a little bit of reading up on that code, since I'm unfamiliar with it and here is what I was able to find out. It can be one of two things, the gas tank cap, or the the charcoal canister VSV. I read this up on how to test the VSV:Since I'm unfamiliar with this particular code, I'll ask Mister_Perkins to chime in on this one

Thanks, but I've had this code for years, and my problem just started now. It doesn't seem like they are related. I'm wondering now if my idle air control valve is really dirty, although again it does not seem like the actual RPM is very high, it just SOUNDS like it is. Ugh. Its never easy.

[Yuko]

Originally Posted by numberforty1

Code is PO446 - Evap Vent Solenoid Problem - Helpful at all?

Ahh, DTC P0446; brings back memories. I had that code for month and after test and cleaning, I just when ahead and replace the VSV. P0446 is strictly an emission code and should not affect the idle speed. The idle air control valve and throttle body might need a cleaning, as you suggested, .

If you want to take care of the P0446, here's a quick DIY on the charcoal canister VSV. The system has two VSV; one by the fuel tank and one by the air box. 9 times out of 10, the VSV under the vehicle jams up and fail, throwing that code. Other times it can be a clogged vacuum line or damage canister.

->DIY : P0446 Charcoal canister VSV replacement

[hill8570]

Have you checked the vacuum throttle stop (looks a bit like a bellows over by where the throttle cables connect to the throttle on the side of the throttle body? When you remove the vacuum line, idle should just up to the 1500+ range; when you connect the vacuum line, the stop should pull in and drop the idle to the 700-ish range (when warmed up).

[numberforty1]

Originally Posted by hill8570

Have you checked the vacuum throttle stop (looks a bit like a bellows over by where the throttle cables connect to the throttle on the side of the throttle body? When you remove the vacuum line, idle should just up to the 1500+ range; when you connect the vacuum line, the stop should pull in and drop the idle to the 700-ish range (when warmed up).

Hi, I'm not sure what you mean, what am I checking and what does it tell me? My RPM numbers are normal, it just sounds like the car is at a higher RPM than it is.

[Mister_Perkins]

Yuko is right, the p0466 has nothing to do with the idle speed.

You'll have to mess with the charcoal canister to correct this problem.

It sounds to me like your timing is slightly retarded or advanced. I would get the motor tdc and confirm the belt is lined up correctly