This one is a short case study, but it shows that, with the right steps, you will find the task easier.
The challenge, in this case, is a Renault C460 lorry fitted with a D11 engine. The customer complained of poor performance and vibration which feels like a misfire. There were no warning lights on the dashboard, which is interesting, as you would assume a misfire would log a DTC. The complaint was verified and we moved on to testing. For misfires, one of the quickest tests you can do is a relative compression. While not conclusive, it can be used to determine which path to take in the testing and the best part is the fact that you don’t have to remove any parts to perform it.