td4 engine shudder

Hi. I have a 2004 td4 auto that is shaking significantly when the engine is between 1500 and 1800rpm. It will shudder while driving and while parked. The engine is quite lumpy at idle but runs smoothly when the revs increase with the exception of the vibration in the 1500 to 1800rpm range. Is this possibly an engine mount issue?

Didn't even know there was an Otago in Aus! Looks like a nice place

Can't really help - but could it be the crank pulley?

have a look down at the pulley area not when the engine is running and look around the bottom pulley if you see metal swarf that looks like fairy dust then it is time to have a new crank pulley this can make the engine unsteady and noisy other than that it could be fuel related. hope this helps

Otago said:

Hi. I have a 2004 td4 auto that is shaking significantly when the engine is between 1500 and 1800rpm. It will shudder while driving and while parked. The engine is quite lumpy at idle but runs smoothly when the revs increase with the exception of the vibration in the 1500 to 1800rpm range. Is this possibly an engine mount issue?

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Hi, I too have a noise that sound very much the same as yours at approx 1500rpm, it does this when driving in any gear or if I rev the engine in neutral, recently had new auxilery and air con belts, mechanic could not find the cause, it seems like something reverberating at the front and when driving it can be felt when holding the gear lever.
Hope somebody has an answer as I won't have a chance to check it for a few weeks.

GrumpyGel said:

Didn't even know there was an Otago in Aus! Looks like a nice place

Can't really help - but could it be the crank pulley?

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Hi. There is some noise coming from the belts in that area so I will have a look.

I was also unaware of an Otago in Australia -until you mentioned it. I'm a New Zealander living in WA.

Thanks for the help.

get a torch and shine it down onto the bottom pulley area you will see the Fairy dust as I call it ,the problem is the bottom pulley is in 2 pieces and it is when these 2 pieces are coming apart it sounds a bit like a motorised lawn mower

Thanks. I will have a good look on Monday. I had a cursory glance from above yesterday and could see no dust. The noise coming from the belt area sounds more like a worn bearing than a lawn mower. I will report back on Monday.

I have had a look at the crank pulley and it appears ok. I think the vibration may be related to the fuel system. I have replaced the harness to the fuel pressure sensor. The very lumpy idle is intermittent -sometimes it runs smoothly when started. I am wondering if I should replace the sensor and if this may be the cause of the vibration?

Just wondering but does it misfire ?

I think so. It certainly has a very significant chug chug when it is lumpy and also pumps out a lot of smoke.

have a read thru these
( unless you've already done so )

td4 engine faults :
http://tuning-diesels.com/75Zt/R75faults.htm

about the 'maf' sensor :
http://tuning-diesels.com/75Zt/R75maf.htm

It certainly has a very significant chug chug when it is lumpy and also pumps out a lot of smoke.

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among other checks ..
remove the dipstick with the engine at idle
if oil pumps out .. it would point towards the crankcase breather system
( worth checking as if it's faulty it would lead to turbo problems in the long run )

I think the vibration may be related to the fuel system

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here's a test that's d.i.y for injector back-leakage

http://www.uniteddiesel.co.uk/docs/...ecking-back-leakage-1398762965-1401121695.pdf

Mine has that problem too. Misfire and plenty of smoke. Been told it's the injector. If not that then the valve stem seals. What colour is the smoke ?

Thanks for the information. I replaced the engine breather filter with the BMW upgrade a couple of weeks ago. The old filter was shot and there was a pool of oil on the top of the engine that had seeped out from under the pcv housing.

I tried disconnecting the maf sensor and this caused a large increase in the amount of smoke pumped out. The vibration also persisted while disconnected.

The smoke while chugging is white.

The smoke while chugging is white

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white smoke be unburnt diesel fuel .. usually has a harsh acrid odour ..
e.g. if an injector nozzle were not to shut in time .. and were to dribble fuel in late after the power stroke
that fuel wouldn't burn properly ..
or if the nozzle spray pattern was defective .. there could be unburnt fuel exiting via the exhaust.
any cause that would leave unburnt fuel in the cylinder would give rise to white exhaust smoke

put a drop of diesel on a hot surface .. like an exhaust pipe 'n see what happens ..
( inject some diesel into a hot exhaust .. and you'll have an effective smoke-screen )

the flash point and autoignition temperature of diesel can be found here:
https://en.wikipedia.org/wiki/Flash_point#Examples

Thanks everyone for their advice and suggestions. I have just this evening replaced the Bosch air flow sensor with a $40 job from China and this has cured the problem. I have heard poor reports about Chinese air flow sensors but thought that at that price it was worth the gamble. It will be interesting to see how long it lasts. I was quite surprised at how much an out of whack maf sensor affected the engine.

that's great news glad you found it