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Service Engine Soon & Self Diagnosis

I have read in this forum about doing a self diagnosis if the Service Engine Soon Light comes up. Link:

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I have a 99 Maxima and the description found in Link 1 is slightly different on my car.

From the image below, at the top of "Hole 1" I see the wordings "IDLE

SPEED" and NOT "SELF DIAGNOSIS MODE SELECT"

My Car:

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's Car: (see the 3rd image)
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I am wondering if the IDLE SPEED in 99 Maxima is same as the Self Diagnosis Mode Select. Can you guys confirm if Hole 1 is the one I should be adjusting to perform the Self Diagnosis to determine the codes? What is Hole 2?

Reply to
survesh2000
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Hole 1 is the correct hole to use in your 99 Maxima. Be careful - the screws on the 99 ECUs are fragile. Use a small philips screwdriver. Be sure to return the screw to its original position (fully counter-clockwise) when you are done retrieving the stored codes.

Another, possibly easier option, is to drive to your local autozone- and have them pull the ECU codes- they do it for free in most areas.

Cheers.

Happy New Year!

Nirav

96 Max GLE, 127k
Reply to
njmodi

Thanks Nirav. Will check with the local autozone here.

Reply to
survesh2000

I did go to autozone and had code P0400-The PCM has determined that a malfunction exists in the exhaust gas re-circulation flow. BTW, the light started coming on the same day I had my oil + filter change.

The autozone guy told me that the problem could be at a couple of places, like the EGR valve itself and something else related to the sensor. Valve alone costs $290.

Can you suggest the sequence of troubleshooting steps I should ask the mechanic to do as I don't want to get ripped off when I go to the dealer or a mechanic.

(I read in another post the the Service Engine light came back 5 times and the dealer charged him each time to get the codes after he tried fixing the P0400 code)

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How often should these valves be replaced or do you suggest replacing the valve or sensor?

Reply to
survesh2000

P0400 most commonly occurs on the 4th Gen Maximas due to clogged EGR passages. That doesn't mean that it is definitely the problem in your case, but it's highly likely.

The fix is to pull the EGR guide tube - that carries exhaust gases back into the intake manifold, and clean it out and also clean out the port on the rear of the intake manifold that the tube connects to.

Cheers, Nirav

96 Max GLE, 128k
Reply to
njmodi

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