Umer95SE

For all those of you who had posted messages regarding the Knock Sensor, Thank You. Your posts really helped me. My experience took about an hour but that was only because I had regular home use tools and not shop level tools. Once I got the bolt loose that holds the KS to the block, the rest took less than 15 minutes. I reset the ECU after I got done, No codes any more. Now my car definetly pulls stronger in the lower revs.

This coming weekend I will be replacing the fuel injectors. My car has 143K miles on it and I feel the idle is a little rough and its running too lean. Last time I had a Nissan tech hook up the Consult (Nissan diagnostic tool), whenever he increased the injector opening/closing timing interval, the engine would settle down and loose that slight murmur. That was when the car had 80K miles. I am thinking the injectors are up for replacement. I like to do preventative maintainence instead of repairs. I got the injectors at $75 a piece at www.partsbin.com

Let me know if you think otherwise or if you have had similar experience and you did something else pther than replacing the injectors.

Toolrocks

iTrader: (1)

Given the money of 6 injectors I would make sure I'd checked all the affordable stuff:fuel pressure and regulator, filter, cleaned iacv, throttle body, plugs, ignition coil packs, just to name a few. Also, to get to the left bank cylinders (by the firewall) will require removing the upper intake manifold - may as well replace it with a VI.

Umer95SE

Thanks, I was wondering what does it take to check and replace the fuel pressure/regulator. I just put in a brand new fuel filter a year ago. What is an IACV. I cleaned the throttle body a few months ago, replaced the plugs with NGKs this summer. Wouldn't the engine shake like a mad dog if the ignition coil packs were bad. I think its the fuel injectors because the engine murmur only occurs at idle or when the A/c is on. As far as I know, at higher rpms, the ECU adjusts the injector timing accordingly.

Dave Holmes

Not trying to sound smart, but considering the cost of a fuel filter, and you haven't changed yours in a year, I'd change it out just on principle. That could definitely solve a rough idle, or atleast be a contributing factor to it. I change mine about every 10,000 miles. It's a cheap enough item (like the PCV valve, air filter, oil filter, etc..) that I actually probably change them way before needed. Speaking of PCV valve, you may want to check yours (some people clean them with carb cleaner. For $1.99, I just replace it). The IACV is the idle air control valve. It fine tunes the amount of air allowed to bypass the throttle plates to maintain a smooth idle. When looking at the engine from the driver's side, it is just past (as air goes) the throttle body, towards the firewall. There are a couple connectors to disconnect in order to take it out. Pretty straight forward once you see it. There have been quite a few posts about cleaning it. With your mileage, it probably does need cleaned. Mine did, and my car only has 68,000 on it. Hope this helps.

Dave