Club 80-90 Forums

My 1.9 diesel runs rough when I first start it up, like its only running on 3 cylinders.It also smokes, white i think, but its dark so I can't be sure.

After 30 seconds or so everything is fine and the van runs well.It will restart fine.
I'm thinking glow plugs but I only changed these earlier this year with a good quality set.
I've removed the two easiest one tonight and connected them directly to a battery. Both glowed bright red within a few seconds.
Is there an easy way to check if the other two are working without removing them?
If it turns out they are all OK where do I look next?

cheers

Gareth

Do you have an electrical test meter? Very useful, about a tenner at most tool shops. You can measure the resistance of the glowplug in Ohms with it in the engine. Good plugs are around 0.6 to 0.9 ohms. Knackered plugs are usually more than 100 ohms, measured between the threaded connection and engine body.

If you haven't got a meter, then you can check using a bulb. A 12V 21W indicator bulb will do. On a good glowplug the bulb should glow at more or less full brightness with one side connected to the battery positive and the other connected to the glowplug threaded connection. On a knackered plug it won't glow at all. Obviously test one plug only at a time with the busbar disconnected!

Is your air filter good and clean? Fuel filter too? Fresh winter diesel in the tank, not left over from the summer?

Both my cars are sputtering for a second or two at -4C the last few days.

Colin

Thanks for the reply, very helpful.
I do have a voltmeter but didn't know how to check to see if they where working or not.

Fuel filter change 6 months ago and just van most weekends so diesel is fresh.
I'll check the airfilter tomorrow along with testing the plugs

cheers

Right I've change the three easy plugs and check the one under the pump. The ones I removed where all OK but had already bought some new ones so replaced them anyway.Change air filter.
Still have the same problem

I checked that I had 12v on the buzbar but only had around 10v and then only until the light goes out on the dash.
I did check the voltage either side of the big fuse and this was 12.65 volts but dropped when glow plug light is on.
I thought that the glow plugs stayed on for a while after the light went out?
Is this time controlled by the glow plug rely?

The plugs take a load of current so your voltage measurements sound about right, allowing for volt drop along cables and connections. You are right in thinking that the plugs are supposed to stay on for a few seconds after the engine is started, and this is controlled by the glowplug relay. Not sure if ALL relays are the same though.

My son is complaining that his 2.5TDi has the same symptoms as you, so I'm going to have a go at the timing in the next couple of days, as I think it might be retarded. (No jokes please) and will post any astounding results here. Just my luck that the cold spell will end, so I won't know if I've cured it or not!

Colin

The white smoke is probably unburnt fuel get it up and running then take it out and give it a good drive to get everything moving and up to temp, we've just had a real cold spell, some people still have it and if the vans not getting used or just does short journeys it probably wants a good run, i only do 5 miles each way to work and back so once a week when i leave work i go the 20 mile long way home


You could also try some injector cleaner through the fuel system to

I've had this problem for a couple of weeks now but it is worse in cold weather.

Once the van is running everything is fine its just the first 30 seconds or so.
I've just ordered some Forte diesel treatment to see if that helps.
Going to Wales on the 28th so that will give it a good run.
I still think something is not quite right with the startup but not sure what

Have you tried giving the glow plugs 3 warm ups to get the chambers propper hot prior to start up ? it has been bloody cold lately

windysurfer wrote:I've had this problem for a couple of weeks now but it is worse in cold weather.

Once the van is running everything is fine its just the first 30 seconds or so.
I've just ordered some Forte diesel treatment to see if that helps.
Going to Wales on the 28th so that will give it a good run.
I still think something is not quite right with the startup but not sure what

Hi Gazz, Wouldnt really be tearing your hair out mate, trying to sort out yr cold weather starting, Mine does the same as your,s sometimes its like as if firing up on 1 cylinder (Diesel Knock on start up) Your AEF 1.9D. Alternative Engine. have you wired up - or connected the cold start Fuel pump advance. if not then thats the problem, My pump does not have any cold starting, Therefore I have to sometimes double heat the glow plugs, If and when she does fire it comes in on 3 cylinders, or so it sound like? a bit of white / blue smoke outa exhaust but only a few seconds, I ussually let her run for a minute or 2 before giving accellerator a small touch,
If its like mine on startup I wouldnt worry mate Seee you at Llangollen, Will be there on Monday,

Hi Jeff

Cold start has never been connected but van has always started up fine without this rough running.This has only started the last few time I've used the van.
I now thinking it might be the glow plug relay.There is no voltage to the glowplugs once the glow plug light goes out, giving the light a couple of goes doesn't seem to help much.The rough running lasts 30-60 seconds.
I'm going to change the relay and see if that helps.
We should get to Llangollen by Monday dinner so cya there

Hi Gazz.
I did have a problem last week she would not fire at all and my glow plug light was flickerig on and off, and was getting a funny sound from engine bay. I checked all my glow plugs and and wiring connections, then went into the Black box, found some crud in ther, and like you I decided to change the 50amp Fuse and I replaced the 70amp relay for a new 1 I had as a spare, (bought from JK), Everything is back and it does start but loike as normal in cold conditions, like firing on 3 on start up. But I know I have now cold start on my pump So i accept that as normal.
See you Monday,
Jeff.

Well....number one son arrived Christmas Day, complaining of poor starting (2.5TDi). Below 4C he had to give the glowplugs 4 shots, then when started he got rough running for 30 seconds and whiteish smoke, before cleaning up and running fine all day.

I checked the timing and it was one-and-a-bit teeth too far retarded on the flywheel (About 7 degrees?) I corrected this yesterday and this morning at -1C it started on the button after 1 shot of glowplugs. Merest hint of splutter and no smoke. (well, just the usual little puff of black)

There's not much room on the V70 (Yes it's a VW TDi engine) to use a DTI gauge without taking off the vacuum pump so I made a cheap device to measure the piston position.



It is simply a long 4mm bolt (with the end filed flat) with a cut down biro spring and a nut and thick machine washer. I poked it in the end of the pump and ran the nut down to the washer which was against the end of the pump. Don't use anything thinner than 4mm as there's a drilling in the centre of the piston, so a thinner bolt won't register with the end of the piston.



Then I measured the position of the nut with an ordinary vernier caliper. With a little practice I got to an accuracy of +-0.02mm.

This is cheaper and easier than using a DTI gauge, can be done with all pipes in situ, and quite accurate enough for my purposes. It is relevant to all Bosch injection pumps but not Lucas (so the method is not applicable to AEF engines, but checking the timing definitely is!).

I hope it will prove useful to anyone wanting to check timing.

I've been having a play with mine this morning.
I added some Forte diesel additive and changed the glow plug relay.
On my van there is a resistor used instead of a engine temp sensor which causes the glow plugs to come on every time the van is started.I disconnected this which allowed me to leave the glow plug light on for 20 second instead of the 8 or so it has been staying on.
It started up right away with only a bit of a splutter so at least I know it is the glow plug circuit that's the problem. I've now reconnected the original engine temp sensor, cleaned all the connectors up and it now seems to be starting fine.The glow plug light stays on for around 12-15 seconds and the power stays at the glow plugs for a further 3-5 second after which the van starts fine, runs smoothly after a second or two.When the resistor was fitted my glow plug light only stayed on for 8 second and if I then turned the ignition off and back on again the light only stayed on for a couple of seconds,also the voltage was cut to the plugs as soon as the dash light went out.I've had the van for 4 years and have never had a problem using the resistor rather than the temp sensor so I'm not sure what's changed unless its just the really cold spell we are having.

I'll give it a couple of days starting to see how it goes but hopefully that's the end of this problem

Glad you got it sorted Gaz - like Jeff says, i wouldnt loose any sleep over it!

Colin - good post. There was similar tool shown on on vwdiesel.net a while back. One full turn is a millimeter of travel?

For some reason i think it got poo poo'd but i cant remember why. Looks perfectly adequate to me.

I ended up getting the DTI and adapter. Not the cheapest....

Ringo

Ringo

The tool that screws into the thread at the end of the pump (I think that's the one you are referring to) is indeed 1mm per turn, and looked like a good idea, until I made one from an old flywheel bolt with a 4mm pin araldited into a central hole. Then when I started to use it i realised that any mistake in forgetting to back out the pin every time before turning the engine would probably write off the pump. As an example, the previous mechanic had marked the pump pulley 180 deg out of phase when he changed the cam belt, so the piston initially moved in the "wrong" direction to what I thought it would! Mistakes like that shouldn't happen, but sod's law states quite categorically.........."Use it enough times and eventually it will happen"

The 4mm bolt is just any old thread pitch, and you actually measure the position of the nut in mm. The spring is just to stop the nut moving accidentally, so it's quite intuitive to use. And no damage done if the engine moves accidentally. I'm a convert.