Missing sensor?

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Jona2487
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Missing sensor?

Post by Jona2487 »

Firstly merry Xmas,
I've spent 2 days searching the Internet and can't find an answer .my van has struggled to start since the weather has got colder,
I think it is missing something. the blue and white wire isn't connected ImageImage

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Jona2487
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Re: Missing sensor?

Post by Jona2487 »

Sorry should have said it's a 1.9 1y engine was a 1.6cs :lol:

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Oldiebut goodie
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Re: Missing sensor?

Post by Oldiebut goodie »

Looks to me like someone has used the 1Y spigot on the rear of the head which doesn't have positions for the temperature sensors instead of swapping over the one from the previous engine. Wild guess - that blue/white wire is for the glow plug sensor ( can't be a***ed to look up the wiring diagrams to check and can't remember) although with it disconnected all that it should do is make the glow plugs stay on for the maximum length of time.
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quattrodave
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Re: Missing sensor?

Post by quattrodave »

Oldiebut goodie wrote:Looks to me like someone has used the 1Y spigot on the rear of the head which doesn't have positions for the temperature sensors instead of swapping over the one from the previous engine. Wild guess - that blue/white wire is for the glow plug sensor ( can't be a***ed to look up the wiring diagrams to check and can't remember) although with it disconnected all that it should do is make the glow plugs stay on for the maximum length of time.

As above, the blue/white wire on diesels goes to the temp sensor on the rear of the head which determines how long the glow plugs are on. With it disconnected the plugs will stay on for max duration, engine hot or cold.
Are your starting problems hot, cold or both ?

Jona2487
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Re: Missing sensor?

Post by Jona2487 »

When it's cold at the moment ,turns over, loads of smoke but won't start ,it has a new battery ,glow plug relay ,I guess glow plugs next step ?

MGP
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Re: Missing sensor?

Post by MGP »

Probably best to start doing some diagnostic work before spending more money, check that you actually have power getting to the glow plugs, if you have remove the bus bar from the glow plugs and check each plug with a multimeter.
Have you got the clear fuel lines in and out of the pump, if you have check for air bubbles whilst your trying to start it.
If the glow plugs check out ok and you have no air in the fuel system then check valve and pump timing.
Glow plugs normally fail one by one causing the engine to smoke and miss on start up which gradually gets worse.


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quattrodave
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Re: Missing sensor?

Post by quattrodave »

Yes it could be, or pump timing out of spec.
I haven't had my diesel long and had a similar problem, the main wire to the glowplug busbar was hanging on by a thread and the pump timing was retarded. It starts much better now, a small amount of smoke but only for 5 secs or so. I really need to change the glow plugs though but it looks pretty tight!
Search 'jx cold start problems' on hear or google, there's a few threads around.
Good luck!

Jona2487
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Re: Missing sensor?

Post by Jona2487 »

Just a follow up changed glow plugs starts fine , I guess will have to live with with glow plug light staying on longer than needs to be :D

quattrodave
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Re: Missing sensor?

Post by quattrodave »

Jona2487 wrote:Just a follow up changed glow plugs starts fine , I guess will have to live with with glow plug light staying on longer than needs to be :D

Out of interest, how easy did you find changing the plugs?
Access looks pretty poor, I've been meaning to change mine for a while now.

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