Hello,

My car failed emissions for ignition timing instability (passed all the emission BTW) - but failed overall as igintion timing is unstable.

I have a knock sensor code (have had it for years, but that has not caused it to fail emissions).

Any ideas - should I replace spark plug and ignition coils and retry before going to re-test.

Also, any ideas which scan tool I should get to monitor things like emission readiness and ignition timing.

Thanks in advance,

 

I think I know what may be going on. It is frustrating to deal with the smog guy - he hardly speaks any English - all he can say - go mechanic, get timing pulley fixed.

My car has had P0325 (knock sensor code) for 5 years. I have never had issues with getting the car to pass (I think, this code is not sufficient to indicate failure).

This idiot (the smog guy) is insisting it is ignition timing issue (with that issue, it would be a miracle that car would pass HC, CO, NOx etc).

If I run a DTC search on p0325 - I get ignition timing, and I guess that is how this moron has concluded that I have an ignition timing issue.

Anyways - I am biting the bullet - and replacing the knock sensor - with Cali spec - it is a pain to replace this (so that I get the free retest the smog place).

I have also ordered an Elm327 based reader (for data logging) to really see what is going on with my car - if ignition timing is not an issue, I am going to complain to BAR about this guy.

One lesson learnt - never go to a smog place where the techs don't speak your language. I guess - need to extend this to everything in general - never deal with mechanics, doctors, lawyers or any professionals, real estate agents - whatever - if communication is an issue.

In the SF bay area - the smog places are pretty much dominated by Vietnamese, Indian and Chinese folks - I will go to an Indian next time (as I can speak their language), or American (as I think I can speak english ;-) ).

I will keep all posted on what I find.

 

You may have to just put the 470k ohm resistor and put premium gas in if you don't use that already so you can pass the test. After the test just reconnect the ks.

 

Unlike WA, where it is a state agency (used to live in Bellevue) that does the emission test (at least, that is how it was, back in 1996/1997) - in CA, it is private shops that do it.

Uniformity and consistency, now that has become a real issue with these places.

 

I just recently hooked a code reader up to my car as well. It also has the P0325 code. The code is "Knock Sensor Circuit Malfunction." I looked further into my code and it turns out that my sensor has an open in it. So...using a scan tool, i looked at my ignition timing...and as it turns out...my ignition timing was between 15 and 22 degrees retarded. So i think that the Knock Sensor is having something to do with the ignition timing be instable...

 

The KS is definitely the reason for that. It has the car in "safe" mode.

If I were you, I would just do the 470K ohm resistor mod like I did and get your power/mpg back.

 

In CA you cannot have any stored error codes, same here in NJ.
You went for insp. tech found the code P0325, YOU FAIL.
Next he tells you it might be ignition,
KS does alter timing, so the tech was technically right.

So, why is he an idiot?

Replace the KS, clear the error code and drive the car around for a week or two so all of the emission controls hit a ready state. If you replace the sensor, clear the code and go immediately back to insp. you will fail for a not ready state.

There are tons of threads explaining all of this. I suggest you do some reading, there is an actual drive sequence that will help you get the emissions back to a ready state quickly.

 

In CA, knock sensor code (which does not cause MIL to light) is no grounds for rejection - and that is the only thing he was finding.

I have a Nissan Quest with same code, and it has passed twice.

My maxima has passed 2 times in the past with the same code.

My cars have passed, and I have used a different shop in each instance. I went to this one as it was very close to work - and I run into this. Not sure if tech is right or not, but it sure is very difficult communicating with him (that is my fault, I should have picked a shop where I could at least communicate with tech).

I have a code scanner, but it does not giving timing stats. I am going to get an Elm scan and log the timing.

If the timing is indeed an issue, I will have to admit that I was being an idiot.

I will replace the knock sensor nevertheless - should have done it a long time back, but California spec car has so much emission stuff blocking access, that I had been putting it off.

 

My 99 is a cali spec. Take the air intake tubing out and loosen the actuator for the swish valves, move it aside, then there's plenty of room to get at the KS. Use a 1/4 drive w/extension to get at the bolt. Took me all of 15 minutes to change mine.
I have no idea why people complain about changing that sensor, it's very simple.

 

Because if you have big hands it is impossible to get to.

 

I don't even have big hands or a 99 cali spec and I had trouble with mine. It wasn't too bad, took me like 20 minutes, but still it is a tight squeeze.

 

it will cost less to replace the knock sensor, buy a ratchet extension and a flexible joint, cheaper than a scanner.

 

Any excuse to buy new tools - I am a sucker for that.

Scanner has been shipped by Elmscan (I already have DTC scanner, but that only retrieves fault codes).

Ordering Knock sensor from DPartsUSA on ebay next (will order Monday - my contribution towards any improvement in sales stats for cyber Monday :-) )

 

Hello All,

I got the Elmscan tool - and at idle, in P or N (I have an auto), my timing advance is 9-11 degrees. This is with the P0325 code.

I then tried replacing the knock sensor, after a few hours, I gave up - Cali spec, too hard to get to, even with swivels and what not. I went to Fry's and got myself some 470 K resistors.

Put the resistor in - and cleared the P0325 code. The timing at idle is identical (smog test is supposed to test timing at idle).

The only difference I notice is under hard acceleration - without knock sensor, the timing was retarded to around 45 degrees, while it is retarding around 40 degrees with the resistor mod.

I called up a friend who has a Maxima (and BTW - found out that he has the P0325 code - car passed smog 2 months back). The readings of my Maxima and his are in the same general range.

I will go to the smog place in the next few days (my computer has to relearn as I have cleared all frame freeze and PCM data) and see if I pass (I suspect I would, as the moron probably failed me for the p0325).

I dunno if I should complain to BAR about the smog place - I know that cars are supposed to pass with P0325 code as that is considered a 'passive code'.

 

i'd report him and drop a dime to INS just for the heck of it. I firmly believe one should adapt to the country, not vice versa. You're in America, by the way, speak American. Ha!

 

Obd says timing fine as per scan tool - smog guy says crankshaft pulley indicates timing is unstable - darn.

Need to find a timing light and figure out what the heck is going on. Harbor freight, here I come.

Will try to inspect and test the sensors (crankshaft position etc).

Car runs so smooth, emissions are well below max - I don't know why on earth timing is unstable as per crankshaft pulley (BTW, I also replaced knocks sensor finally).

As far as talking American - I only drink coke - "in red coloured aluminium cans".

 

Well i must add in that you will NOT fail CA smog for P0325 knock sensor stored.

As far as the guy telling you to replace your crank pulley is because the outer pulley spins on the cracked/worn out rubber between the 2 peice pulley so that will sometimes throw off the pulley timing marks however you shoulda need to get timing checked anyway as these are computer controlled.

BTW its impossible to have your timing 15-22 degrees RETARDED just fyi.

 

Yup, I used "retarded" by mistake - I really meant "advanced" .

 

This ignition timing post is coming up high in google if you searched on "timing smog nissan" - so I will post so that nobody fails our 4th Gen (post 1995 cars) for ignition timing.
BAR - Smog Check Inspection Procedure Manual States on page 22
http://www.bar.ca.gov/80_BARResource...08-09%20V3.pdfNOBODY SHOULD BE FAILING 4th Gen Maxima's for timing issue in California smog tests as these cars are exempt from ignition timing test (based on timing being non-adjustable).

BTW - besides the point - but I went to another smog place, got my car passed, as this guy is refusing to pass it, even when presented with evidence that our cars are exempt from timing test. Further, my harborfreight timing light indicates that my timing is correct - so this test only smog guy probably does not know how to read timing - or has a bad timing light.