2.4jtdm bad vibration after injectors removed and cleaned/refurbed
Hi – Sorry if this is a bit long-winded, any thoughts on this gratefully received. My 166 2.4jtdm has performed very well the last 4 years. Purchased at 120,000km when I put new Cambelt on and changed the brake discs, it is beautiful car to drive, comfortable, effortless, still tight at 187,000km and…….. until two weeks ago no major expense at all.
Last summer I began to feel a slight engine judder on acceleration from 1200 to 2000rpm so because they are cheap and fitted in minutes, on a hunch I put a new EGR valve on which did not change anything. I also changed air and fuel filter. Problem was not horrendous, still getting 40+ mpg and still quite driveable due to massive torque but I kind of knew it was getting worse.
A couple of weeks back I went a stage further and got the ECUMultiscan software and a wireless ODB2 unit to hook up with ECU. (Free download version of this Software is really good by the way). This showed no errors in ECU memory and all parameters, fuel rail pressure, mass airflow etc in spec, however driving around town with a laptop in the car, the injector corrections went from in spec (< +/- 1.0mm3) to up to plus or minus 4 or 5 mm3 on all cyls except 2 which was closer to but not quite in spec. I know these figures are like really bad, so I figured all was not well with the injectors. The vibration from 1200rpm was now very apparent when going uphill, on a cold morning – not nearly as bad when warmed up. Engine always started fine and economy still good.
Original clutch still going strong but the release bearing and DM Flywheel had been on the way out last 2 months so decided to get that and clutch itself done and had the garage take out the injectors so that I could send to a Bosch Specialist for testing whilst the car was on still on the ramp. Results came back that injector units for Cyls 1 and 2 were well in spec but 3, 4 and 5 were just outside limits, so I went with a recommendation to refurbish these three.
Clutch is now a dream, car starts instantly still, but unfortunately the engine runs terribly at all RPM with horrendous vibration like a misfire under load. ECUmultiscan shows that all injector corrections are even worse than before. Car is not driveable because I am sure I will damage the engine if this is not fixed. Spent some time at the workshop today who are v helpful and they confirmed no errors stored in ECU and all important parameters like air mass flow, fuel rail pressure, turbo boost pressure in spec. Obviously first thoughts were, did the injector test/refurb go bad somehow? but given the problem leading up to this beforehand we are wondering if the bad corrections are the symptom of some other engine issue? The technician removed the intake connection on the manifold and looked into the inlet with a torch. As expected it looks well and truly coked and the swirl valves are jammed moreorless in the middle opening position - so that needs to be addressed. Even so I still find it hard to believe that it would make so much difference and it does not explain the stark difference between before and after the injectors were removed and refitted. I know that they went back in the right order as the injector codes in the ECU are the same as before and are still allocated to the original cylinders.
Very next step will be to do a cylinder compression check before I remove and clean the intake which will probably take me at least 2 days and a lot of swearing besides. That provide a better starting point for a diagnosis but the trouble is, unless someone knows differently, I cannot imagine that this could make such a big difference. Hence my slight reluctance to take the plunge.
I love the car and would rely like to hang on to it if possible. Not expecting anything other than commiseration but any shared experiences ideas welcome. Cheers Phil