rough start TD27T 91 terrano auto

[Koolbananass]

Hi

 

just looking for a little bit info, I am still new to diesel and for a few weeks now its been starting rough, takes a long or sometimes 2 cranks before it starts with a little bit off sputter and white smoke, but then be fine for the rest of the day or night until the engine is cold again.

 

I checked the glow plugs but they check out, tested them in the engine then took them out and they all glow red after about 3-5 sec, they do look black and crusted,

I also checked the glow plug relay which is providing about 10.5v. to the glow plugs the relay is active for about 5 secs before the dash light turns off

 

is there any other issue that could cause the hard start problem,

I know low compression can cause hard start but I would imagine that would be on every start not only the first start of the day,

 

can anyone confirm if the relay is only suppose to provide about 10.5v, every thing I Red and watched on the topic showed the relay providing about 12v or same as battery voltage, on mine that should be 12.67v.

 

there is a whole in the exhaust I am picking up a replacement part on Thur, but I somehow don't think that would be related.

 

if someone can show me which wires are for what on the relay I could temp by pass the relay and put it on a switch to see if a longer glow will fix the issue, if that fixes the issue would that mean the glow plugs are going bad?

 

thanks

Michael

[Slartibartfast]

I don't know diesels but I'll hazard a guess that you have a bad connection in the glow plug circuit. Check the connections going to the relay, if you can find them. I would imagine that they're grounded through the motor, like spark plugs. Look for loose grounds on the engine or from the engine to the body, look for corrosion at the electrical plugs, and maybe check for voltage drop across the relay.

 

Found this talking about it on VWs:

[Koolbananass]

thanks for the link, that is a good idea it might help with my problem,

 

it would be good if someone could confirm if there should only be 10.5v coming from the relay.

 

if anyone has a diagram for the glow plug circuit so I can trace back to make sure the glow plugs are at fault cause so far its breathy much just a hunch.

 

thanks

Michael