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Discussion Starter #1
Hi everyone, I don't post on here very often, but am usually on here quite regular following build threads or looking at pics for ideas etc.

Anyway for the last few weeks my diesel 1.9 T4 800 Special (aka Bertie) has not been starting when cold, which has resulted in my using Easystart fairly regularly! Not a thought I relish to be honest. In addition, my temperature guage doesn't work.

Anyway, from readiing the forums, it is very clear that the coolant sensor is faulty, so from advice I was given, I ordered ordered a new one which was a 4 pin and then attempted to match it up.

Now this is when I got in to a spot of bother, because the new 4 pin sensor does not seem to match anything on the engine or hoses? In fact the only sensor I can see is a 2 pin one.

So I spent quite a bit of time on the forums today, trying to find out which sensor it is, but am now totally confused... :eek:

I understand there are different sensors for different engine types, and I understand mine is going to be an ABL or a 1X....

Looking for the part numbers of the sensors which match up to these engines appears to still give 4 pin sensors?

Before anyone suggests it, I can not take out the sensor and check the part number, because of it's location, it would mean moving the rad forward to put it back in again!

Could someone shed some light on the following for me?
a) how to I find out my engine code? It is NOT stamped on the side, however under Engine Number on my V5 there is a 1X as a prefix, so I'm going to take an educated guess that this is the Engine Type unless told otherwise.

b) the type of sensor I require is either 251919501A or D (I believe they are interchangable).

c) this is the only sensor I need to change and that it is likely to cure the faults with starting and temperature guage?

I've added a picture to show where it is, just for clarity.


 

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Hey bud,

Mine is a 1.9td ABL... when mine went it was a 4 pin sensor, its located BELOW the sensor your pointing out!

The one you show faces front To back, below it is a sensor (if yours is the same as mine) that faces right to left (as you look into the engine bay)

You need to ensure the engine is COLD as there will be a loss of coolant when you change it, so dont be an idiot (like me) and do it when its warm!

Ok to remove the sensor, unplug the electric socket to the sensor, then there is a PLASTIC! BE GENTLE! horse shoe shape clip that you need to gently prise upwards, i found if you push the sensor into its socket a bit it relieves the pressure on the clip to make life slightly easier in removing! i used a flat head screw driver to prize the clip, please just be gentle!!

ok, as you release the clip make sure you grab both the old sensor and the rubber washer, you want to make sure at the very least its not still in situe once the sensor is removed, otherwise you have no chance of getting the old washer, new sensor and new washer in aswell!


At this point you will loose the coolant in the filler tank, so have some spare and ready to replace it afterwards. as well as ensuring your not on the driveway as it will go everywhere... yes i also did that too!!!

Now, replace the new sensor and New washer and push it home (quite hard) and pop the retaining horse shoe clip back in to hold it.

One thing to also note, the sensor has specific way round it needs to go, in order for the retaining clip to go home all the way... its pretty clear when you look at the sensor as it will line up with the slots the horse shoe clip goes through... Sorry that is a pony explaination, but it is clear once you have the sensor and try to put the horse shoe clip back in........

ensure the clip has gone all the way down and that the sensor is properly fixed.

Top up the coolant and replace the electric plug ensuring no leaks from the sensor area

Start the van and make sure you have no leakage from the sensor, if you do, remove and refit.

Now cross your fingers and you should now have Glow plug lights on the dash, a tempurature gauge that works and NO MORE EASY START!

Any problems PM me, im rubbish and keeping up with threads!!!

Good luck

Dan
 

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Discussion Starter #4
Upspex, Bertie is a 1996 on a N Reg.


Dan,

much respect for the help mate, I had seen the same advice in various forms on here already, but from reading your reply I decided to go out and check for the elusive sensor one more time, and guess what? I found it!!!

The reason I couldn't find it before is because it was UNPLUGGED!

In fact if you look at my photo above you can even see the blue plastic connector lying further down in the engine bay. :eek:

I couldn't see this before because I was standing slightly further back from the angle the photo was taken, and the connector was hidden from view.

I've just plugged it back in, and Bertie did start, but not as easilly as he used to, so coolant and sensor change this weekend I feel.

Thanks for your help.

Paul.
 

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Discussion Starter #6
Not quite, Bertie's still not starting, so I've still got to get the sensor changed, would you recommend buying and replacing both like some on here have recommended?

Also, I thought it was going to be a simple task of, buy new coolant and sensors, take out old sensors, put new ones in, refill with new coolant, but it appears I need to by the correct coolant, as in G12?

Oh well, a trip to GSF tomorrow it is I reckon.
 

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Not quite, Bertie's still not starting, so I've still got to get the sensor changed, would you recommend buying and replacing both like some on here have recommended?

Also, I thought it was going to be a simple task of, buy new coolant and sensors, take out old sensors, put new ones in, refill with new coolant, but it appears I need to by the correct coolant, as in G12?

Oh well, a trip to GSF tomorrow it is I reckon.
Just an idea but have you checked your glow plugs?

Si
 

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Discussion Starter #8
Yep, they were all changed about 1 month ago, the problem was "cured" for a few days then came back worse. I suspect that we loosened the connector for the sensor when we were changing them, and then it rattled loose, which is why it came back.
 

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Check the glow plug fuse and see if you have 12 volts at the glow plugs. To start a Diesel engine you need diesel,compression,heat and timing ,assuming the engine was running ok the timing should be ok, slacken off injector pipe to check for diesel,ok,check 12 v at heater plug ok,the temp sender will only stop it from heating up so bypass it by wiring directly from + on battery to glow plug for 15 seconds turn key and it should start
 

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Glad to hear you got it sussed!

Any issues give us a shout.

Defo change the coolant and sensor together, youve made the mess changing the sensor, so you may aswell tick another job off the ever growing list!

As people have said, check the glow plug relay, you'll also find the large one at the very top of the fuse box has something to do with the plugs as well (sorry to give you a whole new head ache! but its best to know!)

Id do the sensor, coolant, and then if you still have no joy, check the large fuses in the engine bay just infront of the battery, then the relays. if you cant find anything wrong and still having issues, borrow the glow plug relay and the large (137 I think) relay off a mate and see how you get on....

Make sure they come to you so the van is cold when you try to start it... its no good doing it when its warm... ;) (sorry if im teaching you to suck eggs!)

If your still having agro after that you can grab a multimeter and start testing voltages... I cannot and will not start talking you through that bit, as im clueless! but there is step by step on here somewhere!

Good luck bud

Dan
 

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Discussion Starter #11
Well the confusion has continued...? :*

Sensor and coolant changed this morning - no difference, came back on here and noticed, TimJBurrows post, thanks for that Tim sorry I missed your post before.

So far then;
Glow Plugs Changed -
Sensor reconnected - no difference
Sensor and Coolant changed - no difference


So relay checked, AGAIN! (Had checked this before but just to be sure) - Relay Fine
Checked voltage at glow plug fuse - and when relay active 12V, but 0V when inactive, again proving Relay is fine.
Oh and the voltage both sides of the fuse has been checked, just in case of any ambiguity with the fuse.

So why won't Bertie start?
Is it a case of changing the glow plugs again now? Surely not they were only changed 2 months ago, but I can't see anything between the fuse and plugs.

Also a friend of mine was showing me that if you turn on the interior light then rotate the ignition key to position 1 the interior light dims while the glow plugs heat up, which was happening when they were changed, but isn't happening now?

Any help would be great.
 

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Sounds like the plugs have burned out. Set your meter to ohms and see what reading you get across one of them with the cables disconnected.
 

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Sounds like the plugs have burned out. Set your meter to ohms and see what reading you get across one of them with the cables disconnected.

Thanks Upspex,

having spoken to a mate of mine this morning and being given the tip of putting a piece of wire on to the rail and then brushing it over the plugs to see if there are any sparks, I'm happy the plugs have all blown.

I'm going to guess the plugs were permanently on due to the sensor being unplugged and this has resulted in them blowing.

Looks like another set of plugs to be fitted this weekend.

Cheers for your help.

Paul
 
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