Volkswagen Mark IV Forum banner
1 - 8 of 8 Posts

·
Registered
Joined
·
84 Posts
Discussion Starter · #1 ·
Anyone experienced the above? Seems to be less prevalent when I fill her up with Ultimate Diesel etc.

Had a replacement fuel filter at the last service. Any suggestions?

TIA
 

·
Registered
Joined
·
119 Posts
Ours also suffered this so i replaced the glowplugs its much bettet now but it was not that bad to start with just a slight stutter or extra crank, dont fit copy plugs as they melt lol u can find a thread of mine about it lol. Get some new vw glow plugs in there and it willnprobably solve it. Have u vagcommed it ? Worth doing that too. It can also be caused by a lazy battery so check that out (voltage under load) not static voltage (you will need a good multimeter to record the lowest value) its a bit of a mission to change the glow plugs on the 170 about an hours work but fairly simple with a star drive 8mm long reach and a couple Of spanners let me know if u need and help as i have done two 170s glow plugs now both improved the cold start
 

·
Registered
Joined
·
78 Posts
Ensure you wait for the glow plug lights to go out. I noticed my car will let me start it while the light is still on but it will be rougher. Wait an extra second for it to go out and it's far smoother.
 

·
Registered
Joined
·
84 Posts
Discussion Starter · #4 ·
Never thought to check the battery, will do.

RE the glow light, always pretty anal waiting for that to go out but after the battery test will get them checked. Many thanks indeed.
 

·
Registered
Joined
·
157 Posts
pretty anal? thats the normal crack to wait until the glow plugs have heated up the cyldinders. sometimes, on cold mornings i will wait till the light goes out then turn off/ turn on again twice to get that bit extra heat, always aids the starting of a diesel
 

·
Registered
Joined
·
1,166 Posts
The glow plug light is paramount. The car is essentially pre heating the combustion chambers ready for fuel injection.

The problem posed is that in cold weather, if the engine has not been running (as is the case when the car is left to sit overnight), that large engine block becomes very cold; when one then attempts to start the engine, the cold engine block acts as a heat sink, quickly dissipating the heat generated by the pistons compressing air. The engine is then unable to start, because it can not generate and maintain enough heat for the fuel to ignite. For that reason indirect injected diesel engines are manufactured with glow-plugs in each prechamber.
 

·
Registered
Joined
·
119 Posts
In Short

1) check battery

2) try pre heating the glow plugs 2 or 3 time before starting

if you find that the battery voltage is low when cranking this will cause less power to glow plugs and a slightly slower crank speed = a not so clean start (you could try jumping it from a running car that will provide the extra boost to see if its the battery)

If you find that 2 or 3 glow plug cycles solves the problem i would look at replacing them. Some people say its not worth it and never have done it but i have taken glow plugs out that have been covered in soot and just a buildup of cr*p this will insulate the heating effect of the plug and like any component they do breakdown over time and become less effective. How ever if you plan on changing the plugs. PLEASE PLEASE only use genuine plugs with the part number ending 05 not 03 (the 05 partnumber is a revised glow plug when i changed mine the car was fitted with 03's and i replaced with 05's has made a big difference)
 

·
Registered
Joined
·
84 Posts
Discussion Starter · #8 ·
Didnt realise you could heat it up more than once. Will give that a go tomorrow.

Thanks again.
 
1 - 8 of 8 Posts
Top