[my-tdi-nightmare]

2992 Jetta TDI , hard start even at 90 degrees air temp, after it starts which takes 2 or 3 attempts at 25 seconds each, it will restart in 2 seconds, i check for power at the #1 cylinder glow plug and nothing. glow plugs are new bosh same part # as i removed, Hard starting started about 60 days after changing them.
Does any body know where the fuse is ?? I suspect it to be a fuse over a relay . your thoughs.
Thanks

 

[pearlgolf]

I think it's on the back of the firewall. Have you checked the wiring? This is probably the reason for the bad glow plug but it should start completely fine even without the GP when it's warm. Do you have any codes? Clogged intake? Mine starts in a second. It could be the injection pump timing too.

 

[my-tdi-nightmare]

Yes, i have been through the mil with this POS, the intake is done,turbo was replaced 18 Month's ago and again 3 weeks ago with a clogged waste gate, tranny solenoids and wire harness replaced, timing belt complete with water pump and seals & idlers, cam & lifters, radio, N75 valve,about the only thing has not given me trouble is the license plate .

i dont see anything on the fire wall except the N75 & another vac type solinod that looks just like the N75 ?

 

[chittychittybangbang]

First off, there's no way your glow plugs are causing your starting problem if it's 90 degress out. The manual says that if there's no power at the glow plugs, check the relays and fuses. It could also be a bad wiring harness, a common problem. But that's not causing your no start.

Your 2002 has a wire to each glow plug. 2001 and earlier have all the glow plugs in series. If you still think it's the glow plugs, try unplugging the coolant temperature sensor plug behind and beneath the coolant flange on the driver's side head. This will cause the computer to think it's cold and run the glow plugs at max. If you do that, try probing the other glow plug holes. If you don't get 12V the relay or wiring is bad.

Did you change the relay 109? This controls power to the ECU. Look under the dashboard. If the relay is black, replace it with the updated gray relay 109. This would be a dealer part. Does the glow plug light on the dashboard light up when you turn the key on? While you're there, relay 180 is the glow plug relay.

Are there fuel leaks? If the pump loses prime it'll have air in the fuel lines.

The glow plug fuse is on top of the battery. Check them all for corrosion. The gasses from the battery or salt can cause corrosion.

 

[my-tdi-nightmare]

No visible fuel leaks,tightened all the fuel line clamps,as crappy as the car ran it always started excellent.Once i got it running good then its hard starting LOL
I'll check the solenoids in the AM.
The harness for the glow plugs is a single wire encased in a black hard plastic ( which is all cracked)
there are 4 connections run off this wire, I will look at that closer also.
Thanks for the help

 

[vw709]

The glow plug harness is a common problem. They shouldn't make any difference in starting when it's so warm. They're not even used during start unless it's cold out.