Xantia won't start

uhn113x · Post by **uhn113x** » 24 Jan 2005, 21:33

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by ACTIVE8

I am surprised that Citroen made it more difficult as you say, by not using a connector block.
<hr height="1" noshade id="quote"></blockquote id="quote">
I would think that the main reason is the heavy current in question - any connector would have to be a good one, and, anyhow, you can get at the timer and disconnect the lead there to make current measurements.

ACTIVE8 · Post by **ACTIVE8** » 24 Jan 2005, 21:52

Yes, I agree.
The make I was refering to is German, with Bosch components.
The block is well made, of durable plastic, and allows for easy connection, and is located under a cover in the heater plug relay timer.
I suppose with different manufacturers, and countries of origin you are bound to find many different ways of doing things, but of course it can also be a question of economics during manufacture.

Dave Burns · Post by **Dave Burns** » 25 Jan 2005, 01:34

Whats important as far as testing glow plugs goes is the resistance, should be around 0.5 ohm, if the plug is glowing in the middle or not glowing too well the resistance of it should tell the story.
These are post glow type plugs and stay on for up to 3 minutes, they typically consume some 12 amps apiece, one of the reasons a diesel needs a higher amperage battery than a petrol, the other reason being the higher compression ratio.
Anyone who thinks their XUD will start from cold without glow plugs especially in winter, try it, simply unplug the glow relay and churn away, have a new starter motor standing by though cos' you'll need it.
Dave

Wookey · Post by **Wookey** » 25 Jan 2005, 06:46

Resistance usually works OK for determining dead glow plugs. (dead ones will be open circuit (very high resistance)), but occaisionally you get one that seems to have OK resistance but is still dead/poorly. Measuring the individual current is foolproof so far as I know. As dave says 12A each, which means you need a meter that will go up to 20A (or a shunt), and you can only measure one at a time (all 4 suck 48A). Ohm's law suggets that their resistance should be about 1 Ohm in fact (12A @12Vnominal). The optimum test is take them out and connect them across a battery with chunky wires. See the end glow red after about 3 seconds.
In my experience if you have one dead glow plug then you may not notice most of the time but idle may be a little lumpy just after starting up. 2 dead glow plugs and the thing starts up significantly slower (how long depnds on how good fettle everything else is in) and idles noticeably lumpinly for first 30 seconds or so. 3 dead (I've never got this far except when testing) and it gets quite hard to start.

jakeuk · Post by **jakeuk** » 25 Jan 2005, 22:30

i recently replaced all four champion plugs with really cheap (i think) wellman ones.before i had to crank for 20 or 30 seconds quickly followed by plumes of smoke out of the back embarrasing at least.anyway did'nt do any tests on old ones exept visual, 1 was a horrible nicotine shade of yellow(dead?) another was covered in soot/carbon(dead?)and the other 2 i guess were the ones allowing it to start?
now it starts 1st turn of key with only the tiniest chuff of smoke...might treat it to a new fuel filter soon

ACTIVE8 · Post by **ACTIVE8** » 26 Jan 2005, 20:32

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by jakeuk
followed by plumes of smoke out of the back embarrasing at least<hr height="1" noshade id="quote"></blockquote id="quote">
I hope nobody was standing behind the car, when it did that !

jakeuk · Post by **jakeuk** » 28 Jan 2005, 13:36

only once or twice m8 but its ok,they did'nt half get out the way sharpish[:)]