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!
Got a 2007 hhr 2.4 and have a p1174 code and something to do with fuel trim .. just asking if some had a fix for it .. car runs good starts up fast when I clear the code it comes back in about 60 miles .. so is it a sensor or any suggestion..
The dreaded P1174! :lol: This code is kinda a pain, TBH.
The code definition is Fuel Trim Cylinder Balance Bank 1. The PCM is using the upstream O2 to detect lean running cylinders, and flags this code when one or more cylinders reaches a calibrated threshold.
To be clear, this is NOT a fuel trim issue. You can have excellent fuel trims and still flag this code. Basically, anything that can make the engine run lean (without setting a lean code) , or anything that can cause a misfire (without setting a misfire code) is fair game. Even the O2 itself can cause this code.
The calibrated threshold that the PCM uses to flag this code isn't in the scan data, so you're on your own to figure out which cylinder is causing the issue. Use the freeze frame data as a guide to when the code sets, and monitor the misfire counters to see if one cylinder or another counts up.
Yes it might be the o2 or maybe vacuum leak or a injector .. going to shop in two days and replace plugs there dew and then check exhaust for leaks before bank o2 and scan the car .. it’s a pain but got to nail it ..
Maybe ask them for the spark plugs - in order, so you can see if any are a different colour. I normally poke some holes in a box and number them when I remove spark plugs. Perhaps give them a box with holes to insert the plugs in line with the relevant cylinders to aid diagnostics.
Getting involved in discussions because I have a lot to learn still.
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