I have a Mitsubishi Montero sport 2003 with the 6g72 3.0l v6 engine. Recently it started to develop an issue where it idles rough for like 2-3 seconds only on morning cold starts. After that the car just runs and drives perfectly. Couple of months back, a tuneup was done with new plug wires, spark plugs, new top end seals (all genuine) and cleaned intake systems and injectors.
Would be great to know what maybe causing this issue and should I be worried about it.
Thanks alot.
The issue was fixed after replacing 2 parts. Since there was no error codes thrown, we followed the variables that require when starting up. Fuel, air and ignition. The spark plugs and the plug wires were replaced recently during the periodic tuneup. While doing that, the injectors were checked too. Therefore, those were eliminated and we also knew that the starter and the battery was good working condition.
Next we checked the airflow and its readings which was ok except for the barometric pressure reading. In this particular model, this sensor also resides within the MAF sensor assembly and the reading was stuck at 97. This should change according to the atmospheric changes (so I was told).
And the next culprit we suspected was the fuel filter which was not replaced since new and had about 100,000kms of service.
With these findings we replaced the
Now the car starts and idles just fine. Hope this helps someone else.