Worn injectors can cause rough idle, as well as low fuel pressure(failing pumps), clogged fuel filter, bad pressure regulator, bad spark plugs (did you change these also?) Distributor cap can cause problems too.

Does your economy gauge work properly or seem to behave normally? I had a rough idle one day and it was because the line to the econo gauge fell off the engine.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Yes I changed the plugs, and the fuel filter. I will check the economy gauge but it appears to be working normally.

I have thought about injectors - maybe that's another avenue to pursue, along with a new compression tester!

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Simon Shearer

1986 420SEL

2000 Porsche 911 Millenium Edition Carrera 4
2010 Lexus RX 350
2002 Kia Rio
2002 Hyundai Accent