Kevinmacd

Just curious, anyone have this problem. When the car has been sitting for a long period, cold start the smog pump starts up then I hear a moose type sound. Once the car is running for a short period, the moose noise never returns until it sits for a long time again. Any suggestions? I suspect te smog pump!

Land Jet

I just had this at start up. Made a 1 second moose sound and then went away. Turned out to be a loose top on one of my DV's. It was also throwing a CEL. Don't know if yours is the same but something to consider.

Kevinmacd

Thanks if it were the diverter valve would it only give the moose sound during warm up and not return until it cooled off? I tought divertor vaves would honk when relieving turbo boost pressure.
Please anyone?

Kevin

Is it the gurgling sound after you hear the air pump start? The added air into the exhaust valve/port will cause this sound. When the pump shuts off or when the engine is hot, the sound stops.. All normal..

Kevinmacd

Kev, yes when the pump stops so does the noise, and does not return until that time the pump starts up. You get the pump noise, which is the typical vacuum cleaner noise, and then you get the moose sound, almost sounds lik a diaphram is resonating.

Kevin

Kevin is the noise coming from the exhaust or from the engine compartment. The reason I am asking is> you have a EGT change-over valve. We are starting to see corrosion with the valve and piping. You have to pinpoint the source of your moose sound.

Kevinmacd

Kev It's from the engine compartment, and I think you hit it right on the head, its in the vicinty of the air pump but further down. I suspect the changeover valve, I just can't see he darn thing, even when I trace the input hose from the pump.

Kevinmacd

Cold start up last night no sound, cold start up this morning no moose sound! Go figure!

Last930

The temptation to make moose jokes is KILLING me !!

Kevinmacd

Go for it!

Macster

Shouldn't the urge be to kill moose (and squirrel)?

Sincerely,

Macster.

Kevinmacd

Well the moose is no more, way home tonight, got a cel, the moose sounded and sounded as though it was shot, 0491 secondary air injection valve. So now can someone tell me how long to replace, do you have to drop the engine, and where is it located. I know its on the right side, I suspect by the airepump?

Kevin

The basics are this.. When the airpump is on at start up air is pumped into the exhaust ports.

When the pump is shut off the EGR valve shuts so that you don't have hot exhaust back-feeding into a plastic electric airpump. The valve is located on bank 2 right in the intake/injector block. It is a Bitch to get out and remove. You will have to drop the engine to make enough room to get at it.

It's not a tough job, it will just take alot of labor. You will have to drop your engine and tranny.

Jdiesel

I have the exact same problem same check engine light code same symptoms, i have been driving it without fixing it however. how bad is it to keep driving with it like this? I assume other than an annoying check engine light its not doing any damage is it?

Macster

Hard to say but it is probably not good. May not cause problems right away but you really should consider getting the problem corrected.

If the secondary air injection system isn't working properly then upon cold start no additional air is being fed into the exhaust after the exhaust ports to help the converters burn the extra gasoline in the exhaust.

Over time (how much time?) this could cause some damage to the converters from gasoline being burned with insufficient oxygen.

One concern I would have would be the very fine passages in the converter might become partially clogged with carbon/soot build up. This build up could interfere with proper exhaust flow and if allowed to continue could cause uneven heating in the converter which could lead to mechanical failure. Even in the short term, the blockage may not clear up/go away after the secondary air injection system is fixed.

(I snuck a peek at my Boxster's passenger side exhaust manifold from the downstream end -- the exhaust manifold was removed along with the camshaft cover to replace a failed camshaft actuator solenoid) and could see the exit end of the converter. There are many very small openings through which the exhaust gas flows and it is in these passages heat and the catalytic material and oxygen combine to process exhaust gases properly.)

Sincerely,

Macster.