Glowplug override mod .. questions

[Mike Smith]

I'm considering trying to do a glowplug override mod ..
I'm experiencing starting issues, however when the car requests the help of the glowplugs it starts first time,
so my question.. is it feasible to use a simple push switch that sends a feed to the glowplug relay, and to just give it that little extra help to start, or would it be better to use another relay to supply the fuses under the ecu tray under the hood, providing these are on the output side of the glowplug relay.
Welcome your thoughts and help ..
Mike

[iwaters]

The glow plugs are only used when the engine is cold to warm the air in the cylinders. Because your engine starts fine when the ECU activates the glow plugs but doesn't when it isn't then it would indicate that you have a warm starting problem.

Activiating the glow plugs in this condition is unlikely to fix your problem, you need to tackle to root cause of the problem. A fault code scan would be a good place to start.

[Mike Smith]

Had a scan done, it threw up inconsistent readings on the mass air flow so that was changed and also the coolant sender was changed, still the problem persists..also changed 6 glowplugs, injector bleed off pipes (only the ones on the injectors though, the 2 long ones have small non return valves in them so wasn't able to do them.
New filter and top valve changed.. so not sure where else to look ?
Have noticed 1 small air bubble at the top of the clear fuel pipe near to the filter, and when I started the car a few more appeared ..
Regards
Mike

[iwaters]

I think your fuel system needs bleeding.

[Mike Smith]

Is that an easy job for a DIYer?
Regads
Mike

[iwaters]

You need someway of operating the fuel pump remotley, a switch into the fuse box will work and you will need some clamps to clamp the lines and depending on the enigne you may need a suction pump.

PM me your email address and I will send you the details from the workshop manual. You can decide yourself then whether you think you can do it.

[paul b]

So the actual problem is the car starts fine from cold, but struggles when starting warm?

I had the above issue with my old Skoda Octavia, which also had an air bubble in the fuel line, with more of them appearing when it went to start.

The problem was the battery. The battery was working properly but it was under powered, not the correct one for the car.

Maybe look into that, a local motor factor can tell you how powerful your battery should be, you can then compare that figure to the one on your car's battery.

[Columbo]

What's your mileage?

Could be a fuel pump problem. Seem to remember some else with a simular warm start problem.

I wouldn't even go down the glow plug mod route. The glow plug circuit is complex and still operates after the engine has fired up for a minute or two depending on the temp.

[Mike Smith]

@ Paul B.. had the battery checked by 2 garages and it checks out ok, it is the correct one too
@columbo..97,000 on the clock, cambelts done at 80,00 (previous owner who only did the belts!)

[A4 Lad]

I think your fuel system needs bleeding.

Dismiss this. Your fuel system does not need bleeding. When your engine runs, it means it is bled. You may possibly have air entering the fuel system though. If the car is sitting for a while, the fuel can return to the tank which then means it has to churn before getting up to the engine.

Lets start at the begining ;

Do you have power to your glow plugs ? You can force your engine to trigger the glow plugs for this test by removing the temperture sensor and with it connected, spray brake cleaner on it, making it very cold and indeed making your glow plugs power when the ignition is turned on.