Monday, 17 September 2012

A glow in the dark before you start.


Glow plug not working. Note the reading on the meter.
The glow plugs are a preheat device allowing the engine to start more easily from cold. There is an icon on the dash to show that this is in progress when the light go's out the van is ready to start. This sign does not tell you that the glow plugs are in working order. Most people only notice there is a problem when they have trouble getting the engine to start and stay running first time which is something I have been experiencing with the van.

 

It is a quick and easy test to do with a volt meter if you have one. The air filter housing needs to be removed first.  Set the volt meter to resistance (ohms) on the meters dial. Touch the two probes to gather, this will give you a reading which will also show that the meter is working. Remove the wire connection from the top of the plug place one probe on the top of the plug where the wire was attached. It does not matter whether it is the black or red probe. Then touch the other probe to the hex nut that is part of the plug. Be careful not to touch the same area the other probe is already attached to as it will give a false result. If the meter gives a reading the heater element is OK. No reading means that it is a dud and needs to be replaced.
Working glow plug. note the reading on the meter.

 

Be careful when removing the glow plugs from the engine. Remove any debris from around the base of the plug before  removal otherwise it will fall into the cylinder. If you have trouble loosening the plug try not  to be to heavy handed you can round the nut off or snap the top off (they are made from aluminium) leaving the rest of the plug stuck in the head - which will be a whole lot of trouble. If the glow plug feels that it is over tight, spray some easing oil on the plugs thread and try again. If it still will not move, put it all back together and run the engine till it is hot and try again.
Tool for the job

 

To remove the glow plugs you will require: a 10mm deep socket, Wobble head extension bar - at least 150mm long, a ratchet and or tee bar. The glow plug at the front of the engine (left hand side) may need the top engine mount removed to allow proper access to the plug this depending on engine fitted. The torque settings for the glow plug are Fifteen to Twenty Newton meters.


Tuesday, 4 September 2012

Vivaro couldn't pull the skin off a rice pudding.


The van has developed a running fault that started a month or so ago and has become progressively worse. It has taken us some time to chase down the cause of this problem.


The symptoms:

 This fault shows it's self when you drive away from a stand still. You have to push down the accelerator pedal alot further than is normal to get it to speed up enough to change up to second gear. On lifting your foot off the accelerator pedal to change gear the vehicle speeds up while you are changing up. On pressing down on the pedal again the van struggles to gain speed. It feels like it is holding back.

 
Thought process and action.
 
This suggests that it is a fuel problem. But it has nothing to do with fuel, injectors, high pressure pump, fuel filter or related sensors. Another suggestion was the turbo but we could hear it spooling up. We checked the  turbo pipes, ducting were tight and not blocked. We found a couple of lose hose clips but not enough to cause power loss. Also checked to make sure the waste gate solenoid worked as it should.

At one point we thought the ECU needed a re-boot, again it did not seem likely. Thinking about it, it was a flow problem the only other thing that came to mind was the air flow meter. Before we paid out on a new meter we surfed some motoring forums for pointers but no one had this fault it would seem. We came across a thread that suggested the changing of the airflow meter would sort it out but this gentleman also had the crank sensor replace. After a short discussion we decided to go with the air flow meter. Bingo! got it in one and what a relief, it would have been an expensive mistake otherwise.


Air flow meter
 

Extra work.

 
While we had the air filter housing off,  which is a pig remove, we thought it prudent to check the glow plugs as it only takes a couple of minutes with a volt meter. We found that two of the plugs didn't work. The ERG valve drew my attention because the inlet manifold was covered in oil  suggesting the gasket had failed or the bolts were lose. You have to be patient when removing it as it has a build up of oil residue. On removal, it was found clogged with a thick coagulated oil  that took a bit of cleaning up.
 

It runs and pulls like a train now. The rice pudding skin doesn't stand a chance!