If this needs to be moved please do so.

My wife drives and 03 Altima 3.5, VQ, any way there is some dieseling or knock when lightly applying the accelerator. It doesn't seem to occur if you get into the pedal with moderate or higher force.

She has been buring permium from shell, 93 octane, for at least the last two tank. I replaed the air filter about a two weeks ago but my wife claims these sounds pre-date the change. SHe says sometime it is very strong then there are times where it only occurs faintly.

I have heard both strong and slight today but it seems to sort of be in decline. I just checked idle, ignition timing and searched for any stored codes and everything sems to be normal.

I used the scan tool to check the ecm# and have the folowing digits 9J074 but I am not certai if that is complete. I checked alldata.com for any TSB and there is one that pertain to lost power:

Classification:
EC03-004

Reference:
NTB03-023

Date:
March 15, 2003

I really would appreciate any feedback/insight you can afford me. I do plan on taking it in to the shop but want to be armed with info first.

Regards,

Noah

 

Experiment with different makes of gas. I know that my G35 and old Maxima would ping when using Shell V-power fuels. With BP fuels, there is no pinging.

 

Sounds like you have some carbon buildup in there. Probably creating some hotspots and/or just increasing compression leading to the ping/knock. Some dealers carry the 44k http://www.bgprod.com/products/fuelair.html

Its about as good as it gets for cleaning up the innards. If you cant find it, then put 2 bottles of the Techron total fuel system cleaner or the Valvoline Synpower in a full tank. You might have to do it twice if its really bad, but it should help. I do the 44K every 15K miles before oil/filter change. Never a ping even on 87.

 

she has been pretty consistent on getting fule from the same shell but has deviated a few times over the past month.

I have heard the BG ads on AM talk radio but have not heard of anyone using it. I'll run this tank down and see if I can find a BP or Mobil around our house.

Thanks for the feed back.

 

I was back under the hood today to check the air intake and filter to make sure it was fitted properly. I figure ti would have thrown a code if it was getting unmetered air but what the heck.

More focused test driving, no wife and kids in the car , has shown that this occurs at 2000RPM +/-150. I reset the ecu and took it out for a test drive and it seems to have helped a great deal but I really need to have my wife drive as it seems more prevalent with her driving style or lack there of


Thanks again for feedback.

 

I retarded the iginition timing and it semed to help. I also reset the ecu and added some of the techron fuel additive. According to my wife the problem is gone.

She does a lot of stop and go driving so the carbon build up is a distinct possibility so I took it out on the I for some spirited driving to clear the congestion.

No I have to fix here squeaky seat.... another topic in itself but what is it with Niss/Infni car seats???

Thanks for the tech tips.

Have a pleasant weekend.