Smoking TDi 75

simufly

simufly

A2OC Donor
United-Kingdom
Although it passes the MOT emissions test, if I leave my car for a while say a couple of days, it smokes very badly for the first few miles. ( It was flagged on an mot a couple of years ago)
Possible leaking injector?
 
Or Glow plugs need replacing, as the chamber doesnt get hot enough on start up, I changed mine smoking went away as its very cold at the moment.
 
If its smoking for a few miles I would say that isn't glow.plugs, as surely they've done their job and the engines warming up. It could be over fueling because of coolant temp sensor perhaps? Maybe it thinks it's colder than it is.
Any idea what colour smoke?
Grey (diesel) blue (oil) white (water) etc?
 
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does it ever do the "Friday night carpark meet" revving for a second after startup? That's the classic indicator of injector wear. Went away when I fitted as set of refurbed AMF injectors.
 
CrispyEdd said:
If its smoking for a few miles I would say that isn't glow.plugs, as surely they've done their job and the engines warming up. It could be over fueling because of coolant temp sensor perhaps? Maybe it thinks it's colder than it is.
Any idea what colour smoke?
Grey (diesel) blue (oil) white (water) etc?
Click to expand...
Certainly not white, more blue/grey.
 
Great suggestions made. I'd like to add the following.

1.Injectors - possibly
2. Sensors - coolant temp, radiator lower hose temp, Maf - test with a multimeter and vcds
Valve stem seals - maybe
Turbo oil leak- maybe
Vacuum leak - maybe
Torsion value - maybe

Air in fuel - possible, by adding a clear hose just before the tandem pump using an 8mm straight connector (copper pipe) to join to the existing fuel line at one end of the clear hose and jam the other end where fuel line was disconnected. (You'll have to loosen both 10mm bolts to temporarily release the metal fuel lines).
Go for a drive park up overnight.
Get an assistant to start the car the next day while you video the clear section of pipe with your phone.
Hopefully no bubbles.
Best of luck.
This is a super low cost diagnosis technique.
A totally sealed fuel system is required on a tdi.
 
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If the fuel has no bubbles the next step would be a service. A fuel and air filter plus an oil change. Followed by removing the fuel pick up in the tank and giving the basket a good clean.
 
simufly said:
Although it passes the MOT emissions test, if I leave my car for a while say a couple of days, it smokes very badly for the first few miles. ( It was flagged on an mot a couple of years ago)
Possible leaking injector?
Click to expand...
Hi there
Both my tdi 75 and my T4 Transporter 2.5tdi had blue smoke on start up because I filled them up at the supermarket. Switched to using Esso BP or shell and both vehicles run much better with little to no smoke.
 
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