Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
This is sort of a general question on this dtc since I see it a lot and really hate seeing it, ha. Here's an example...
A few weeks ago I had a pathfinder in with this code. There is a bulletin for it that includes an ECM update if there are no drivability issues. I applied the bulletin, road tested, shipped it. It came back yesterday with the same code. I looked at ffd, checked scan data values, nothing seemed abnormal.
I don't like that this code has "circuit" in the name, because it sets anytime the signal value is outside of the expected range. What I usually find with this one is a vacuum leak, but fuel trims were fine. Another issue I see is dirty throttle body,where the plate might be sticking.
I tried the wiggle test and didn't see any drop outs. I ended up cleaning the throttle body but I'm not really sure what else I could have done here, and I hate not finding a definitive issue. Service info isn't very helpful here. It says to check for air leaks and provides MAF voltage values at idle, 2500rpm and 4k, and looking for a linear change with rpm, which I had.
I also opened a case with our tech support to see if they had any other info and they asked me to send ff data since they said that is helpful with this code and I'm waiting to hear back now. What would you be looking for there? throttle %, load, app, fuel trim?
Any egr present on this engine?koer with the egr signal circuit wire back probed,then turn engine off and look at signal return,i have carried out this test on the diesel engine and know that it works.
No EGR on this vehicle. I might just have to wait to see if it comes back. It had a small evap leak (p0442) that I found at the vent o-ring. I do remember service info staying that the evap pressure sensor could be an issue with this dtc. I'm not 100% on how that is, but I don't think the leak is related.
Yep I checked all of that stuff. I've never seen it actually be a circuit issue even though I know it could be. I've seen the signal voltage look crazy with an aftermarket air filter but this all looks fine and is seated. No exhaust restrictions. No drivability issues and alphas are very good. I thought for sure the update would fix it.
Tutti57 wrote: Yep I checked all of that stuff. I've never seen it actually be a circuit issue even though I know it could be. I've seen the signal voltage look crazy with an aftermarket air filter but this all looks fine and is seated. No exhaust restrictions. No drivability issues and alphas are very good. I thought for sure the update would fix it.
Nissan Technician
I actually just did the same update on a Maxima for the same code. :silly: Haven't seen it back yet? But now you've got me doubting. :lol:
I couldn't find anything wrong with that one, either. Checked pin fitment at the MAF, VE, alphas, intake boot, filter, all the usual suspects. Never could reproduce it on my own.
