Alright, I've got a 2000 se manual and I've got an emission test due in a week. I'm getting these codes p1320 (came twice), p0300 and p0171... I got these from autozone... I recently moved and my old mechanic is 70+ miles away and I don't want to get riped off by some here cuz the codes aren't really giving me much insight to what's wrong..... after reading some of the post on here I feel it may be the MAF senson since the car stops kicking after like 3500 rpm..

Can any of you pros help me out?

Thanks

 

And I cleaned the maf sensor but that didn't help much

 

go here http://www.nicoclub.com/FSM/maxima/2000.5_Maxima/ec.pdf

you can do a search for your codes and check the diagnostic proceedure.

it looks like you either have a bad coil or injecter in bank 1. Which is the three cylinders closest to the firewall. follow the diagnostic proceedures on the FSM linked above, and you'll find your problem. OR, If you're loaded, replace all of your coils and injectors on bank 1. that can be pricey though.

Also, this happened to me once, and it turned out that the rubber duct connecting the throttle body to the air intake had a huge rip in it. pull the duct off and inspect it.

 

Hey thanks.. i changed my maf sensor and wow it runs great but i still have the p1320 light for the coil.. I read the coils with a multimeter and this is what i got

Well here are my readings not sure which ones coil 1 2 3 4 5 6

But ill begin with the the front of the car going left to right

+1, -2

Left: 1.52 Middle: 1.55 Right:1.41

Back of the car

Left: 1.33 Middle: 1.41 Right: 1.47

I think its the back left one... but id rather get some advice

 

I had coil problems and all 6 coils read similiar to what you got. But then I reversed the ohmmeter connections and found 2 coils really out of range.

 

which ones were they and what did you do the ohmmeter if you still remember..

 

If you read the plugs are all the plugs burning the same? Inspect the coilover plug igniters for carbon trails/cracks visually. If you can't find anything reaasemble everything and place a inductive pick up around the wire harness of each plug and shine the timing light somewhere you can see it real good at and look for any misses and uneven ignition thru the timing light image! You might find the defective missing coil this way.....

 

hey thnx guys.. I fixed them .. i replaced coil number one which is back left and after that i went to autozone and they ran my car again and this time i got a code for cylinder two misfire so i replaced coil number two drove it llike 38 miles and took it too emissions and passed .. lets see if the light comes back on im at 45 miles right now .. THANKS FOR ALL YOUR HELP!

 

(Sorry, I don't know why I am not allowed to post in a new thread. )

My 2000 failed emissions test yesterday. I was wondering if it is possible to tell what is the most likely cause...

The car (In Canada) has 86,000Km (about 52,000 miles), had all coils replaced back in May, but not the spark plugs.

The readings of the test were:

HC ppm 40Kmh: 5 (pass) - idle: 6 (pass)
CO%: 40Kmh: 0.01 (pass) - idle: 0.00 (pass)
NO: 40Kmh: 1273 (fail, limit is 450) - idle: no measure (why, don't know)
RPM: 40Kmh: 1723 - idle: 799
Dilution: 40Kmh: 15.01 (valid) - idle: 14.90 (valid)


Can bad spark plugs cause these bad "NO" readings? That is my suspicion (or hope). The car hesitates when accelerating and there is a general lack of power, although gas mileage is great.

Thank you.

 

Ursus-do you have any current SES codes showing?

 

The infamous P1320, that's why coils were replaced with brand new ones. Thanks.

 

Anyone? What is the most likely cause of these readings (failed emissions test)...

HC ppm 40Kmh: 5 (pass) - idle: 6 (pass)
CO%: 40Kmh: 0.01 (pass) - idle: 0.00 (pass)
NO: 40Kmh: 1273 (fail, limit is 450) - idle: no measure (why, don't know)
RPM: 40Kmh: 1723 - idle: 799
Dilution: 40Kmh: 15.01 (valid) - idle: 14.90 (valid)


Someone told me the 5 HC readings was too lean as well.

My suspicion is spark plugs, or timing, am I way off? what else ??

Thank you.

 

Car went in for diagnostics. They pointed out to a bad MAF sensor which would not give full readings. Car went for 2nd test, without any mechanical changes made. Here are the results for the 2nd emissions test (load/idle):

HC 2/0
CO 0.02/0/00
NOX 330/NA
RPM 2400/817
Dillution 15.8/15.6

Results: PASS, no mechanical changes made (I changed the oil and the air filter)

MAF sensor was not providing full voltages, recommended it to be replaced. I will try cleaning it first. P1320 still on, recommend changing coils (which were replaced in May... sigh). Also, controlling the egr valve manually reduced the NOX to 31, so egr was fine, but the ECM just does not want to open the egr for some reason (likely the MAF?). The thing is, nobody knows how the computer works and what exactly it does when it does not receive the readings it expects form the sensors. In my case it seems that it is not controlling the egr. Any options very welcome!

I have a number of interesting technical charts as well on the coils and the MAF. My coils are not producing the expected slopes, but more of a square wave. The result is a lean mixture and pinging when accelerating hard.

Car has 55,000 miles (a real lemon in my books).