Technical Anybody see anything wrong + any suggestions???

[Greasytrucker]

Hi just wondered if anybody can help with a starting issue on my 2007 Sedici which I believe shares the same 1.9 Multijet engine as the Doblo. First start of the day is a complete pain up the a*se, you can heat it up numerous times and it’ll churn over, almost fire but then churn over a bit more finely starting with a big puff of white smoke. Once it’s warm it starts fine but then on tickover but only when warm it’s got a funny jingly misfire (sounds like a load of morris dancers) that goes away if you rev it slightly, also if you hold it at about half throttle when stationary and it’s warm it starts to slightly misfire, drives fine though. Have attached some fuel pressure readings when running and not running to see if anybody can see anything amiss?

 

[The Panda Nut]

It sounds like a preheat failure. Probably the glow pugs burned out. These can be tested to see if the resistance is right. The noise may or may not be connected butbmay be due to idle speed being wrong by a small amount and linked to the pre heat system. I have never replced glow plugs but they can require replacement from 30,000 miles up.

Re misfiring, have you checked for water in the fuel filter?

 

[Greasytrucker]

It sounds like a preheat failure. Probably the glow pugs burned out. These can be tested to see if the resistance is right. The noise may or may not be connected butbmay be due to idle speed being wrong by a small amount and linked to the pre heat system. I have never replced glow plugs but they can require replacement from 30,000 miles up.

I’ve tested the glow plugs with a multimeter (3 of them I could physically get to anyway) and 3 & 4 were fine but number 2 was completely dead so I replaced that one. The one to the left I couldn’t even get to enough to pull the plug off the top even with some injector pipes along with various other stuff removed. There’s no flashing glow plug light or anything. Was thinking about having another go at getting to the first one and also replacing the other 2 just to eliminate the problem. Any ideas how long the fuel pump should run for when ignition is turned on as mine hums for about 7-8 seconds before cutting out. Just seems fuel related to me

 

[Greasytrucker]

It sounds like a preheat failure. Probably the glow pugs burned out. These can be tested to see if the resistance is right. The noise may or may not be connected butbmay be due to idle speed being wrong by a small amount and linked to the pre heat system. I have never replced glow plugs but they can require replacement from 30,000 miles up.

Re misfiring, have you checked for water in the fuel filter?

No I haven’t checked for water in fuel filter in all fairness

 

[jackwhoo]

Leak off test the injectors

What is rail pressure when cranking but not firing?

How many miles vehicle covered?

Use meter to check glow plugs get power when meant to - report result.

Yes the in tank electric lift pump sounds correct running for 7 or 8 seconds at key on.

Read rail pressure when lift pump running - report result

 

[Greasytrucker]

Leak off test the injectors

What is rail pressure when cranking but not firing?

How many miles vehicle covered?

Use meter to check glow plugs get power when meant to - report result.

Yes the in tank electric lift pump sounds correct running for 7 or 8 seconds at key on.

Read rail pressure when lift pump running - report result

It’s done 122000, will have to wait till it’s cold to check rail pressure when cold. Not sure how i can check for power to glow plugs as have to strip injector pipes and all sorts off to get to plugs on on top so gonna make a mess when I turn ignition on to check for power won’t it? Plenty to check though lol

 

[jackwhoo]

Have a look if you can get a volt meter probe on anyone of the plug wires without disturbing anything else or back probe one of the plug wires at the glow plug control unit.

 

[Greasytrucker]

Have a look if you can get a volt meter probe on anyone of the plug wires without disturbing anything else or back probe one of the plug wires at the glow plug control unit.

So follow the wires back to the control unit end and make sure it’s chucking power out to the 4 wires when ignition is turned on?

 

[The Panda Nut]

It ougt to go if three are working but while they may test up OK I have seen bad performanceon working ones. I have a feeling on some older cars if one doesnt work they may possibly all not work but wouldnt expect a newer car design to do this. I think there is a device on the pump that turns up the fuel and also increases idle speed for a couple of minutes fter starting and the control unit should keep, the plugs glowing at a lower level once started. I suppose the misfire could be a head gasket symptom so worth checking the hoses arnt over pressured once warm. I wuld be suprised if this is the case as at 122000 its now just nicely run in! It may be necessary to get the injectors checked of this persists.

What does the exhaust look like when its revving / misfiring are you emitting any smoke or steam at this point.

Whats the cam belt looking like too - if it has one.

 

[Greasytrucker]

It ougt to go if three are working but while they may test up OK I have seen bad performanceon working ones. I have a feeling on some older cars if one doesnt work they may possibly all not work but wouldnt expect a newer car design to do this. I think there is a device on the pump that turns up the fuel and also increases idle speed for a couple of minutes fter starting and the control unit should keep, the plugs glowing at a lower level once started. I suppose the misfire could be a head gasket symptom so worth checking the hoses arnt over pressured once warm. I wuld be suprised if this is the case as at 122000 its now just nicely run in! It may be necessary to get the injectors checked of this persists.

What does the exhaust look like when its revving / misfiring are you emitting any smoke or steam at this point.

Whats the cam belt looking like too - if it has one.

Cambelt was changed at 90,000 so thats fine, no smoke once it’s started. One thing i do know now that needs replacing is the MAP sensor in the inlet, I cleaned the EGR out a few weeks ago but forgot about the MAP, took it out today and it was totally blocked up to the extent that it didn’t want to come out of the hole so that won’t have been helping! Have cleaned for now but will be replacing. If i can eliminate glow plugs then injectors will be the next place i’ll be looking!

 

[The Panda Nut]

That MAF may explain all as far as running is concerned. I know from out Panda (petrol) that these things make a significant impact on such things. At leat with diesel you really have only timing, compression, injection and fuel quality plus of course the myriad of really useful sensors to deal with.

 

[jackwhoo]

So follow the wires back to the control unit end and make sure it’s chucking power out to the 4 wires when ignition is turned on?

Yes

 

[Greasytrucker]

Yes

 

[Greasytrucker]

Results of leak off test. First picture is 3mins on tickover, second picture is 1min at 2000 rpm. Does that help anybody? Obviously on the 2000 rpm test cylinder number 1 was considerably lower than the rest

 

[jackwhoo]

How much does each bottle hold in mililiters?

 

[jackwhoo]

Initial thought is they look ok , unless the bottles are able to hold a lot of fluid

 

[Greasytrucker]

How much does each bottle hold in mililiters?

I measured one of the bottles and confusingly filled up to 10 is approximately 50ml so have worked it out and posted pictures. Seems a bit high to me but not sure what maximum amounts are for this engine?

 

[jackwhoo]

There are different ways to interpret the leak off test.
I think they are fine.

 

[jackwhoo]

Rail pressure when cranking?
Power getting to glow plugs?

 

[Greasytrucker]

Rail pressure when cranking?
Power getting to glow plugs?

I’ll check the rail pressure when i get a chance. Want to stop it ticking over like a bag of crap when warm as my first priority as i think it’s all linked to the starting problem. Tickover is fine when you finally get it going but once up to full temp it’s got a miss on tickover, also got a miss if you hold it at part throttle when warm. I’ll post a video when i get a chance