[Engine] Engine vibration at ~1,500 rpm (all gears)

[saskak]

Hi All,

I get this rather pronounced vibration at ~1,500 rpm in all gears. The car is a Pug Partner (a badge difference) 1.6HDi (M59; 2007; 9HXC engine; 90bhp; no DPF/FAP) with ~97k miles.

The whole car shakes. Maybe I am exaggerating a bit, but the vibration is pretty noticeable. Anything under and above 1,500rpm is very smooth. Power delivery is also as it has been. It is just that when it crosses the 1,500rpm the whole thing really vibrates. There is not anything out of the ordinary with the car, fuel, oil, air filters and oil replaced on a regular basis (~6k miles). No errors reported by the ECU/BSI. It does not matter if the rise in rpm is done slowly or very quick, i.e. flooring it.

AFAIK the ~1,500 rpm is when the turbo kicks/spins up. The turbo seems pretty healthy, no excessive shaft movement, no lateral or axial play in the shaft. There is a small amount of black stuff around the seat of injector 1 (most left one), but that has been there for quite some time and it is not chuffing/ticking, etc. I am thinking of a leak-off test to see if an injector under load is partially blocked or delivers abnormal amount of fuel. As far as I understand there is not a standard amount of fuel returned, but one should look at the variance around all 4 injectors. Potentially <25ml per min under idle or is it 30sec.

Would anyone know what could cause this?

Cheers,
saskak

[polar]

A decent diag would help to locate the problem, other than that its guessing.

So ill have to have a guess - the symptoms you have could be the EGR valve, but thats just could be? If you do have oil/tar round the injector you really need to get the seat recut and the seal replaced asap, the vehicle is relatively low mileage so its worth doing, no big shakes to a decent garage.

[saskak]

A decent diag would help to locate the problem, other than that its guessing.

So ill have to have a guess - the symptoms you have could be the EGR valve, but thats just could be? If you do have oil/tar round the injector you really need to get the seat recut and the seal replaced asap, the vehicle is relatively low mileage so its worth doing, no big shakes to a decent garage.

Thanks polar. I already cleaned the EGR valve and there was not much deposit anyway and it did not make any difference with respect to the vibration. I replaced it ~2 years ago, so pretty much brand new. I did notice a slight catch on the pin that rotates the actual valve shaft, so perhaps there might be a bit of a lag to close, i.e. to overcome the catch. I might have to investigate a bit more to see where the catch is, I think is in the spring mechanism in the electronic part.

I could potentially replace the injector seal myself, but was wondering if one really needs to re-cut the seat or just proper cleaning. That is, if the seat is not damaged of course.

[polar]

A decent diag would help to locate the problem, other than that its guessing.

So ill have to have a guess - the symptoms you have could be the EGR valve, but thats just could be? If you do have oil/tar round the injector you really need to get the seat recut and the seal replaced asap, the vehicle is relatively low mileage so its worth doing, no big shakes to a decent garage.

Thanks polar. I already cleaned the EGR valve and there was not much deposit anyway and it did not make any difference with respect to the vibration. I replaced it ~2 years ago, so pretty much brand new. I did notice a slight catch on the pin that rotates the actual valve shaft, so perhaps there might be a bit of a lag to close, i.e. to overcome the catch. I might have to investigate a bit more to see where the catch is, I think is in the spring mechanism in the electronic part.

I could potentially replace the injector seal myself, but was wondering if one really needs to re-cut the seat or just proper cleaning. That is, if the seat is not damaged of course.

Advise recut the seat (you can get a cheap kit off ebay) also check the vacuum pipework to the turbo - remember some kind of solenoid re wastegate and turbo boost fueling??? Someone may know what im thinking about and have the correct component parts, my memory is not the best at the moment!

[saskak]

Advise recut the seat (you can get a cheap kit off ebay) also check the vacuum pipework to the turbo - remember some kind of solenoid re wastegate and turbo boost fueling??? Someone may know what im thinking about and have the correct component parts, my memory is not the best at the moment!

The pipework looks pretty good, no cuts, nothing. I will have to investigate how to test the wastegate, in case it is somewhat partially stuck or slow to react.

[saskak]

It is not the EGR valve. Just fitted a blanking plate and the vibration was exactly the same. At least I know it is not the EGR.
Next is to check the wastegate and a leak-off for the injectors.

[polar]

It is not the EGR valve. Just fitted a blanking plate and the vibration was exactly the same. At least I know it is not the EGR.
Next is to check the wastegate and a leak-off for the injectors.

That was a good idea - any chance you could get some real time data from a lexia, as it may help.

[saskak]

It is not the EGR valve. Just fitted a blanking plate and the vibration was exactly the same. At least I know it is not the EGR.
Next is to check the wastegate and a leak-off for the injectors.

That was a good idea - any chance you could get some real time data from a lexia, as it may help.

Yeah, that is probably a good idea. I can get some real data to see what is going on.

[cancunia]

Yep, same as Polar has suggested, map some of the readings on a graph using Lexia or PP2000, or Torque. The ones that come to mind are RPM, Boost, Rail Pressure, MAF Airflow. As you've blanked the EGR, not too much point in looking at that, although you will almost certainly get an error code generated.

[saskak]

Yep, same as Polar has suggested, map some of the readings on a graph using Lexia or PP2000, or Torque. The ones that come to mind are RPM, Boost, Rail Pressure, MAF Airflow. As you've blanked the EGR, not too much point in looking at that, although you will almost certainly get an error code generated.

Thanks, I will see what I can log. I already removed the blanking plate once I saw that it makes no difference. I prefer the reduction in the nox.