My 1997 Q45 won't start today. Yesterday I moved the car around in the garage and only left it on for a short time, turned it off and left it overnight. I tried to start it today, however when I turn on the ignition, I hear a loud sound as long as they key is turned, which stops when I turn it off, so it seems that the car is cranking but the engine won't turn over to start. This happened to me before and we thought I had flooded my car and had to have it towed to the dealer. The repair order said the AAC valve was out of range and the car was flooded, and the dealer reset the AAC valve as the repair resolution.

They also replaced the engine oil because I flooded it, however I didn't spend much time cranking the car this time, so I don't think it would be flooded again.

I have heard that starting this car without leaving it run for an extended period of time is a common problem with the Q45s and thought if it is the AAC valve again there would be an easy answer to resetting it, however we are not sure where to find the valve

Does anyone have any knowledge of this problem and if the AAC valve reset could be related and if it is something easy to do? I can't believe I will have to pay another tow charge and our local dealer moved out of the area but am uncomfortable trying another gas station for fear they will not have knowledge on what to do.

Any help or advice I can get would be very much appreciated.

My 1997 Q45 won't start today. Yesterday I moved the car around in the garage and only left it on for a short time, turned it off and left it overnight. I tried to start it today, however when I turn on the ignition, I hear a loud sound as long as they key is turned, which stops when I turn it off, so it seems that the car is cranking but the engine won't turn over to start. This happened to me before and we thought I had flooded my car and had to have it towed to the dealer. The repair order said the AAC valve was out of range and the car was flooded, and the dealer reset the AAC valve as the repair resolution.

They also replaced the engine oil because I flooded it, however I didn't spend much time cranking the car this time, so I don't think it would be flooded again.

I have heard that starting this car without leaving it run for an extended period of time is a common problem with the Q45s and thought if it is the AAC valve again there would be an easy answer to resetting it, however we are not sure where to find the valve

Does anyone have any knowledge of this problem and if the AAC valve reset could be related and if it is something easy to do? I can't believe I will have to pay another tow charge and our local dealer moved out of the area but am uncomfortable trying another gas station for fear they will not have knowledge on what to do.

Any help or advice I can get would be very much appreciated.

You were wise to change your oil because the fuel/air mixture is very rich on a cold start. When you immediately shut it off before letting it warm completely, the cylinder walls are washed of oil and thus there is no compression. Did they clean the AAC valve also? How about the line to the EGR valve? Replaced fuel filter within the last 12k miles?

Mis-adjusting the AAC valve is a common cheap fix for a dirty intake path.

You were wise to change your oil because the fuel/air mixture is very rich on a cold start. When you immediately shut it off before letting it warm completely, the cylinder walls are washed of oil and thus there is no compression. Did the clean the AAC valve also? How about the line to the EGR valve? Replaced fuel filter within the last 12k miles?

Mis-adjusting the AAC valve is a common cheap fix for a dirty intake path.

The only thing showing on the Infiniti work order is that the diagnostics said they found the AAC valve out of range and reset it, along with replacing the oil and oil filter. No mention of cleaning the AAC valve or the line...

Is the reset/adjust to the AAC valve very difficult to do; can it be done manually or do you have to use a device to perform the reset/adjustment?

Standard setting is 2.5-3 turns out from fully closed.

Unless it and the EGR valve are clean, the TB and intake path is clean, and the hose connecting the EGR valve to the plenum is clean, it may not work.

Adjustment assumes as new engine operating condition.

Should not eally affect starting, though. Mainly for idle compenstation when accessories cycle.

to start a 'flooded' Q45--floor the throttle--keep it floored until it starts. This turns off the fuel injectors. Crank no more than 15 sec per attempt, with at least 1 min between attempts. After 5 such attempts, wait 30 min to allow starter to cool off--keeping the accelerator blocked open. Use a watch to time all attempts. After 5 attempts, smell the exhaust pipes--if no odor of gasoline detected, you engine IS NOT flooded--other causes are possible: Fuel Pump not operating #1 camshaft position sensor #2

When you get it running, add a large can of TECHRON to the fuel tank to clean out the fuel injectors and intake valves.