AX 1.5D starting probs

[RussellF97]

It does seem a bit young to be needing the injectors sorted, but in line with my principle of trying the cheapest and easiest options first, you could always bung some injector cleaner through it to see if it makes any difference. It did on mine for a while, but the injectors were really too far gone for it to be any sort of long-term cure.

As others have pointed out though, the most likely cause of your problem could be a glowplug or two not playing the game.

When you do get to the bottom of it, it would be interesting to know what the problem was... Good luck!

[3ps]

Yes I had already decided to replace all of them if need be. They are cheap enough.

Not sure how to test them while removed TBH.

[JohnD]

.Not sure how to test them while removed TBH.

Use a pair of jump leads. Battery neg to body of plug. Battery pos to plug terminal. Should be an instant glow from plug tip.

[3ps]

OK so I tested them this morning.

4 of them, I started with the rightmost one, for no particular reason.

I got my son to flick the ignition on whenever I heard a relay click in the engine bay and the V went to 0.

Anyway

No 4: about 12
No 1-3: various readings about 8-11

I did a bit of faffing around and started to get lots of readings of 10.7/10.8

So I did another clean test and I got 10.7 / 10.8 from them all, consistently.

The ignition would have been on/off quite a number of times a that point.

[3ps]

TBH I don't trust myself on these things so I will probably repeat it this evening.

[RussellF97]

They are best tested off the car. You will need a lead (at least of the gauge of the wire feeding the plugs) with a large crocodile clip either end and a pair of mole grips (to hold the glow plug).

Attach the lead from the pos on the battery to the connection on the end of the glow plug. Then earth the glow plug on the neg terminal and note if - and where - the glow plug glows. It should glow at the tip. Anywhere else and it's duff. Do not touch the glow plug for a while afterwards - it will be HOT!

[3ps]

OK I think I can manage that. I hope it will be easy to take them out.

[Xantidote]

As previously said, you can't beat testing the glowplugs out of the car.

However, before removal, (and here I'm speaking from experience with my Xantia where it's a bit of a pain removing some of the plugs), where voltage testing suggests a problem, I check the resistance of each individual glowplug, using a multimeter. Do this with the common rail busbar/feed wire disconnected, so that you are only checking each glowplug individually. On the Xantia, I expect a good glowplug to give a reading of approx 1/2 - 3/4 ohms (yours could be different?). A reading of (say) 12 ohms would mean it's going high resistance, and no reading at all means its burnt out - either way, goosed!

If you find all readings similar, then I'd suggest your problem lies elsewhere.

Word of warning when you check for such low resistances. Make sure you make good electrical contacts, as a poor contact on your meter's probe will give you an erroneous reading, leading you up the garden path

Good luck

[3ps]

OK, but I'd have to fiddle/faff around a bit to see if I can do that.

[Xantidote]

Well, it's whatever you find easiest, and what tools you have to hand

[3ps]

OK so I had another go this evening.

I decided to repeat the voltage test of the morning.

So again, one by one, having hte ignition turned on and measuring each plug until the relay clicked off.... and just as this morning, I got very bad readings from them all, of about 8-9.

Then I tested one or two quickly again.

Then I repeated the test, and just as this morning, they all read 10.7/10.8 consistently.

I'm not sure what the significance of this is, but the fact it happened twice must mean something??????? Any idea what it points to?



I then tried to measure the resistance but got nowhere.

I then tried to remove the glow plugs, but my size 10 socket was not deep enough to fit on.

I then tried to measure the resistance again but got odd readings, so I tidied up.

After tidying up I realised that that I had not isolated each glow plug when checking the resistance.

So that was it.

[Xantidote]

Hope you have better luck tomorrow

[JohnD]

I then tried to remove the glow plugs, but my size 10 socket was not deep enough to fit on.

I.

Save yourself all this heartache and take out the plugs for a test. You'll need something like this to make it easy:-
http://www.ebay.co.uk/itm/3-8-Dr-10mm-D ... 3a78efe255" onclick="window.open(this.href);return false;

A lot of glowplugs are 12mm - but as you say I seem to recall the 1.5D being 10mm

[3ps]

OK so I repeated the test this morning. My reasoning was that if I tried it to the point that I was getting 10.7/10.8 on each, that it was then working properly and the car would start well.
Again, I got spurious readings and after a while got correct readings.

But the car still chugged for a while and failed to start.

I'm pretty sure that all my testing of glow plugs last night ran the battery down.

I now have it on a trickle charger.


Does anybody have any insight into why I always get low voltage readings initially, and then it seems to work OK?
Could it be that I have 4 dud plugs? It would seem odd.

Perhaps I should just replace all 4 and see what happens, but I'm trying to keep expenses down.


I wouldn't just have had a bad battery would I???????
I wouldn't have thought so as when the car was hard to start it was chugging away without sounding feeble.

[Xantidote]

Have to admit I'm not sure exactly how you are doing the voltage test. If you are sticking the meter's probe on to one glowplug, with the other 3 glowplugs still connected in the circuit, then it will only tell you the supply voltage. If this is what you are doing, then getting 10.7-10.8 volts at the first attempt suggests to me most of the glowplugs are OK, maybe 1 duff. You should note that once the glowplugs have been activated, and therefore warmed up, then if you try testing again immediately, you'll get slightly higher voltage readings, as the resistance of the glowplugs will have increased becaused they've been heated up during the first test.

Hope this isn't too confusing. At the end of the day, the sure way is to remove them, and test on the bench, but testing with the glowplugs in the engine saves the hassle of getting them out - isn't there always one awkward one.