Knock with a rich mixture?

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I am getting two codes off of my parents 2001 Altima. One is a P1126 and the other is P0325. On is a knock and the other is a faulty thermostat or temperature sensor. The t-stat has been replaced within a year so I'm leaning toward it being the faulty two wire sensor on the back of the block. My question is would it be basically running open loop would a slightly rich mixture cause it to knock over time, causing the knock code to come up with the temperature code?? Thanks
 
I don't know, I am just wondering why the knock code is showing up.
I think my scan tool said it was pending though. I am going to replace the temperature sensor later today and see if that fixes things. From what I gather the computer thinks the engine hasn't reached 195*F in a certain amount of time. Coolant is good and I would expect that a t-stat would go out in a years time so it leaves the sensor and/or wiring harness. I have had to replace the sender for the dash gauge so I suspect the other sensor to be bad too.
 
Check the temperature on the scan tool early in the morning after a cold soak, should be within a couple degrees of ambient. It could still easily be a bad thermostat.

You may need some high-test gas and an "italian tuneup", you sound a little carboned up. Especially if it keeps running cold.
 
Those knock sensors throw codes all the time on Nissan either from the sensor being bad, or some actual mechanical or spark noise. However, that sensor does not do anything to the car. It does not adjust air/fuel or even turn the SES light on.

The p1126 temp not reaching specfified temperature is very rarely a temp sensor problem. It is quite possible that your thermostat is not opperating correctly. Did you replace it with an OEM t-stat??
 
While there's never a full guarantee even on OE thermostat, I have no faith on aftermarket thermostat and won't be surprised if it failed.

So, to sum it up nicely: check/replace your thermostat if it's deemed faulty, and seriously consider factory OEM thermostat.

Q.
 
Originally Posted By: Quest
While there's never a full guarantee even on OE thermostat, I have no faith on aftermarket thermostat and won't be surprised if it failed.

So, to sum it up nicely: check/replace your thermostat if it's deemed faulty, and seriously consider factory OEM thermostat.

Q.


I used to have no problems with aftermarket thermostats, but over the years I've seen them go bad, or causing other problems such as this. In fact I just installed a aftermarket thermostat in my Toyota about 2 months ago, and a couple of weeks ago while driving to work I noticed my temp gauge was not rising and I was freezing! Sure enough, took that thermostat out and tested it, and it would take about 10 min to close, and not even seat correctly.

Most times the OEM stat is only a few bucks more than the aftermarket. I'd say throw an OEM thermostat in and try again.
 
@Johnny248:

"Used to be" aftermarket thermostats were ok quality, but not anymore.

Also: most of the aftermarket thermostats may not be designed to bear the thermal characteristics that the engine manufacturers had in mind, even though the opening temperature may be the same. As a result: it's not uncommon to see weird issues from engine management/control perspectives where the culprit lies within a faulty/intermittent/lazy aftermarket thermostats.

While many ole-tymers may argue that aftermarkets worked fine for their vehicles (prolly over 10 yrs old? still back in pre OBD-II days or even older?), this observation no longer holds true due to the fact that (a)with the ever-demanding EPA and emissions control and engine management systems (OBD-II), thermostats play a vital part of the game for being able to regulate the water jacket/cooling temperature; (b)aftermarket thermostats quality no longer holds up especially when most of them are now built in the far east, and quality has been mediocre at best.

Q.
 
In my Jeep, the cheapo Stant ran a little cold, and wasn't 100% consistent. However, the more expensive (bigger mechanism) superstat works great, and holds rock steady temp at 195 - 200* when cruising (195* t-stat).
 
well i changed the temperature sensor took it for a drive (20MINS) and no codes yet. Will take it for a longer drive tonight. I did use an after market thermostat as our closest dealer is 85 miles away and the oreilly's 8 miles up the road had one. If the code comes back then I know its the thermostat.
 
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