Is there any harm in ignoring EGR and Knock Sensor codes?

Here's the story...My SES light was on for over a year. The code saidf something was wrong with my EGR valve. I just let it go for a while and during a very cold week here in NJ, my SES light went off and I was able to take my car to inspection and it passed. Just today, my SES light came back on with both the EGR valve code AND a knock sensor code. I'm strapped for cash and can't afford to fix it through the dealer.

 

welcome to my world my friend......

 

No real harm, no.

 

Same here. It's probably been over a year I've had those codes. No problems.

 

my check engine light has been on for so long my bubl burnt out, seriously it did

 

the EGR valve code AND a knock sensor code. I'm strapped for cash and can't afford to fix it through the dealer.[/QUOTE]

I don't know about the EGR, but the knock sensor will knock lotsa mpgs off. It won't hurt anything else, as long as you run Premium gas. If you use cheap gas, you'll get knocks when you punch out, which [I]could[I] damage the engine.

 

Not very likely.

 

's right, but depends on the driving. I just did the resistor KS bypass, and don't use cheap gas. been OK for over a year.

 

Doesn't even really depend on the driving, either.

With the P0325, it won't advance the timing for more power. You'll be at a 'safe' level.

Even with the KS bypassed, I've never once had knock with low octane.

 

Get the EGR fixed when you can but otherwise P0325 knock sensor won't set a check engine light thus won't cause you to fail emissions either. The EGR will set the light and will cause a failed smog test.

 

knock sensor is a common problem for gen4 maximas, fix egr, most people dont bother with knock sensor. i did cuz i hate to see the check engine light

 

Why did you post that random picture?

If you want to show a pic every time you post, just use your sig like everyone else.

And the KS will not light the CEL.

 

Thats what I said, i don't know why the other poster said he changed his for a SES light. Its very tought trying to sell a $200 knock sensor to most customers since they don't actually see a check engine light. I usually gotta tell em "for improved performace and fuel economy, we strongly recommend replacing your detonation sensor, this sensor allows the ignition timing to advance which equals to more performance/economy but if it goes bad then those are greatly reduced". Most people are like whatever, i don't feel anything.

 

Yea, I can only imagine trying to sell the KS work (especially at book time, and at retail KS price). Most people probably think you're just trying to rip them off.

 

Well I prob shouldn't be saying this but since i work in Berkeley and the majority of customers are all about being green and clean (tree huggers) most do go for it. All you gotta do is tell them they're not burning the fuel as efficient as they could be thus increasing a little emissions. But we usually cut them a break and only charge like an hour and sneak the sensor out. Sometimes ill throw one in on a major service or something, just charge em like an extra half hour if they do spark plugs and maybe a combustion chamber cleaning (seafoam).

 

You don't got $50 for a KS? That's how much I paid on ebay. There are some cheap ones for like $30 shipped, but I went with OEM for a bit more for piece of mind. It came with dealer packaging and it works great for me. I installed it within an hr or so cause I needed to run to the part store to get tools I didn't have to make it easier.

As for EGR I have no clue. Never messed with it, but I highly recommend you replace your KS asap for better performance and most importantly better mpg.

HAHAHA! I thought I was crazy or something, but I guess your right he does post random pics and its just weird, but funny lol.

 

Thanks for all of your responses. I'm gonna keep my eye on my fuel mileage and take it from there. Like I said before it was weird, me SES light was on for a year and then one frigid week it went off and I was able to get through inspection. I don't have to go back until 2011 so I'm good with that.

 

honestly if ur **** about gas mileage like i am....change the knock sensor....with mixed driving i used to get 24-26mgs....with the knock code i went down to 18-19...and a full tank doesnt last me a week anymore....look at it this way for 50 bucks or so its almost (mind the almost) like getting an "awesome-kick-in-the-pants-my-car-feels-like-its-on-caffein" feeling....its like night and day....i would look at it as a cheap and cost effective power adder lol

 

Yea when you accelerate from 1st or 2nd gear and don't feel and hear your car's wheels are spinning you know you needa change your KS. Once you change that you will kick yourself for not changing it sooner. For a cheap fix like this you should change it ASAP!!! I'm glad I did. Then again to each their own.

 

 

The knock sensor wont cause the CEL to come on, but it does affect the gas mileage. I find a front O2 sensor affects the gas mileage more though.

 

Yea I've been driving with a faulty knock sensor for years now, and still no problems...Just worry about proper maintenance of your max and that's it...tune up, and no cheap gas etc...

 

I found the KS from the scanner (no CEL), and replaced it with one from eBay ($50). This was about a year ago, and so far so good. The mileage improved from 18 mpg to 23 , that alone probably paid off by itself when the gas was $4/gal.

 

My KS has been out for over 4yrs. and EGR code for over 2 and I have not noticed any problems. I'll still get 21-25mpg with daily driving. It wont hurt your engine

 

doubt you had much luck geting it inspected. it wont pass with c/e light on. least not here in pa..

 

I had noticeable increase in performance, and no more surging acceleration after replacing my ks.

 

fix the knock sensor u could kill your motor with a bad knock sensor mine use to knock hard when i jam the gas the sensor is about 150$ could get it on ebay for about 40$

 

My KS went because of my coil and after replacing the coil I am getting 18mpg so I can't wait to change the KS. When I had the bad coil in there and cheap gas it would run like crap. Better on premium so that's all I run in there from now on. If I'm going to be spending money on good oil and filters, plugs etc. then I figured I should do the same with gas.

 

i have a stock maxima and always fill up with premium so i just put a resistor in the KS and no more code

from what i've read it's ok to do if you're stock, else it's not very safe as someone already said having a KS can save your engine.

 

correction

Welcome to everyone's world. Owning a Maxima with a Po325 and po400.

 

When my coil crapped out it was pretty bad so I don't know if I'd want to not have a working KS.

 

 

[quote=petro2342;6861304]You don't got $50 for a KS? That's how much I paid on ebay. There are some cheap ones for like $30 shipped, but I went with OEM for a bit more for piece of mind. It came with dealer packaging and it works great for me. I installed it within an hr or so cause I needed to run to the part store to get tools I didn't have to make it easier.

Knock Sensor $50 on Ebay or you can pay about $130 at Auto Zone...

 

It's amusing to read that people can go years with a CEL, yet regularly do performance upgrades.

 

It's all in your priorities.

 

knock sensor is $12 on ebay

 

+1

I cant stand seeing the CEL on.

 

My knock sensor went bad awhile ago and have no plans on fixing it soon

 

I used to always race a tundra on to the freeway after our classes ended with my stock 99 i30. I lost 100% of the time. I had an egr and Knock sensor code that I always put off. Repaired (Cleaned) the egr to get rid of the light and still lost a few more times. Got kragen to price match autozone's $75 to their $200 KS and installed it. The next few races I tied but lost in the game of chicken due to the lanes joining.

That alone tells me that the ks affects the performance.

 

To be honest the EGR only cools the cylinders by injecting exhaust gas (Which does nothing) back into the cylinder at specific RPMs and whatnot and so, if it gets stuck OPEN then that is a huge problem and exhaust gas is entering your cylinders all the time, but if it gets stuck closed then to be honest the only thing that can go wrong is your NOx emission will go up because combustion temps are going up, and pre-detonation which is caused by excessively high combustion temps.

EGR is a emissions thing and doesn't do anything for performance.

Or so I've heard.