My ZX has developed a cold start problem. It has gotten worse since I had the cambelt changed.
What happened this morning was I turned the key and the starter seemed to not turn over as positively as usual. I turned over again with a dab of throttle and the engine fired once and died (I had stopped the starter motor and taken my foot off the throttle on the first turn).
On the third turn the engine started OK.
I can't see any obvious deterioration in the fuel lines...
The fuel primer pump never seems to be absolutely firm - but not completely empty either.
I have a new battery. New glow plugs (bar 1).
Any ideas?
By the way - whta is the 'WAXSTAT' and where can I find it. Is it like a diesel version of the choke?
ZX Diesel cold start
Moderator: RichardW
I take it from "New glow plugs (bar 1)." that the one behind the fuel filter has not been changed. It is probably likely that if one were to fail it would probably be this one as because of it's location it would be the one to get left.
Check to see if you are receiving power to you glow plugs on initial key turn by connecting a lamp between the common glow plug rail and earth. The lamp should light to indicate the glow plug relay/timer is working.
Check the fuel return lines on the top of the injectors. If they are perished or hard they may be letting in air. This will cause an air lock preventing full fuel flow, and hence preventing a good start. The single blank found on the far right injector usually is the first to go because it is made out of a slightly different rubber ( and is hard to check because its behind the fuel filter again)
If the cam belt has just been changed and the problem has only appeared after the belt was done, it could be that the timing is slightly out - Either by the belt being fitted slightly out, or the pump timing may have been adjusted for the previous belt setting which was out.
Contact the garage that did it and check to see whether they pinned the pulleys in the right places to ensure the engine possition was correct before they fitted the belt. If they did and you can't find any other faults it might be worth getting the timing checked. This is a diesel specialist's job really, as it involves DTI's etc, but your probably looking at £30-£40 in reality to get it done.
I hope this helps, and I have no doubt more advise from other members will be forthcoming.
Andy
Check to see if you are receiving power to you glow plugs on initial key turn by connecting a lamp between the common glow plug rail and earth. The lamp should light to indicate the glow plug relay/timer is working.
Check the fuel return lines on the top of the injectors. If they are perished or hard they may be letting in air. This will cause an air lock preventing full fuel flow, and hence preventing a good start. The single blank found on the far right injector usually is the first to go because it is made out of a slightly different rubber ( and is hard to check because its behind the fuel filter again)
If the cam belt has just been changed and the problem has only appeared after the belt was done, it could be that the timing is slightly out - Either by the belt being fitted slightly out, or the pump timing may have been adjusted for the previous belt setting which was out.
Contact the garage that did it and check to see whether they pinned the pulleys in the right places to ensure the engine possition was correct before they fitted the belt. If they did and you can't find any other faults it might be worth getting the timing checked. This is a diesel specialist's job really, as it involves DTI's etc, but your probably looking at £30-£40 in reality to get it done.
I hope this helps, and I have no doubt more advise from other members will be forthcoming.
Andy
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Dave Burns
- Posts: 1915
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- Location: United Kingdom
- My Cars:
- x 2
Hmm..probably the plug not changed is the one behind the injection pump, especialy the Bosch pump, all the others are not too difficult.
The waxtat I suppose can be thought of as the diesel version of the choke in a way, though it doesn't alter the fuel air ratio for cold starts as with a petrol, it advances the injection timing slightly making starting a bit easier and low speed idle a bit smoother and faster so stalling is less likely.
The main component if it is screwed into the thermostat housing below the fuel filter, a cable runs from it to the injection pump where it pulls a lever, the cable should be slightly taught and the lever against its stop when the engine is cold, the cable is released by the expanding wax as the engine warms up, the lever should travel to its opposit stop and the cable go slack when the engine is hot.
Dave
The waxtat I suppose can be thought of as the diesel version of the choke in a way, though it doesn't alter the fuel air ratio for cold starts as with a petrol, it advances the injection timing slightly making starting a bit easier and low speed idle a bit smoother and faster so stalling is less likely.
The main component if it is screwed into the thermostat housing below the fuel filter, a cable runs from it to the injection pump where it pulls a lever, the cable should be slightly taught and the lever against its stop when the engine is cold, the cable is released by the expanding wax as the engine warms up, the lever should travel to its opposit stop and the cable go slack when the engine is hot.
Dave
Try changing the glow plug behind the injection pump, best to use a flexible socket spanner, this is a spanner with socket both ends and the
sockets are secured with a pin, hence the flex. I have just done mine
and this plug took 20 minutes to get the terminal nut on!!! as I had to
hang the nut from a piece of wire onto the thread of the plug and then
turn the nut using a screw driver! This was after a had tried everything else.
My 1993 ZX TD (250,000km)was slow to fire and even with a new battery it did not help a lot but in desperation I changed the plugs and it fires first time now.
Good Luck
Mike
sockets are secured with a pin, hence the flex. I have just done mine
and this plug took 20 minutes to get the terminal nut on!!! as I had to
hang the nut from a piece of wire onto the thread of the plug and then
turn the nut using a screw driver! This was after a had tried everything else.
My 1993 ZX TD (250,000km)was slow to fire and even with a new battery it did not help a lot but in desperation I changed the plugs and it fires first time now.
Good Luck
Mike
hi
thanks for all of your replies to my question in this forum. A great help.
To do with the ZX cold start...
I checked the glow plug power with my multi meter. It is providing a steady 12V and shuts off after 20-30 secs or so. I have checked the resistance on the old plug behind the pump (that can't be removed) and that seems to be ok (offering the same resistance as the other new plugs).
So that doesn't sound like the problem.
I have looked at the fuel leak off pipes on the injectors, but can't see anything as the intercooler is in the way.
<b>What I can see</b> is that there is an awful lot of what I suspect is old diesel fuel that looks like it is getting blown out of either the rightmost injector / or out of the top of it (as I can see fuel pooled around the base of the injector). I am pretty certain this isn't oil as the consistency is all wrong and the fresh stuff around the injector base looks very like diesel.
Is it worth taking the intercooler off to investigate? And if one of my leak off pipes is damaged, can I replace it? where is the best place to look for a replacement, and what should I ask for?
thanks again,
john.
thanks for all of your replies to my question in this forum. A great help.
To do with the ZX cold start...
I checked the glow plug power with my multi meter. It is providing a steady 12V and shuts off after 20-30 secs or so. I have checked the resistance on the old plug behind the pump (that can't be removed) and that seems to be ok (offering the same resistance as the other new plugs).
So that doesn't sound like the problem.
I have looked at the fuel leak off pipes on the injectors, but can't see anything as the intercooler is in the way.
<b>What I can see</b> is that there is an awful lot of what I suspect is old diesel fuel that looks like it is getting blown out of either the rightmost injector / or out of the top of it (as I can see fuel pooled around the base of the injector). I am pretty certain this isn't oil as the consistency is all wrong and the fresh stuff around the injector base looks very like diesel.
Is it worth taking the intercooler off to investigate? And if one of my leak off pipes is damaged, can I replace it? where is the best place to look for a replacement, and what should I ask for?
thanks again,
john.
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- Location: United Kingdom
- My Cars:
- x 2
Leakoff pipe is available on the gsfcarparts.com web site or just go to your local specialist and ask for leakoff pipe, try and steer clear of the braided fabric covered stuff, it doesn't seem to last to well, the gsf stuff is the real McCoy.
Get enough to do the lot (which isn't much) then take the intercooler off which is not difficult and get stuck in.
Either get a replacement blanking cap for the righthand (No 1) injector or cut a short piece of pipe and shove something down it like a ball bearing that is a snug fit to blank it off, there is no pressure in these pipes when the engine is running.
Be very careful not to drop anything down the open intake while its off, stuff some clean rag in to prevent it.
Dave
p.s whats this about a glow plug that can't be removed, it can be trying but it can be done and on a ZX isn't that bad, on a Xantia its bad due to ducting and other crap not found on a ZX.
Get enough to do the lot (which isn't much) then take the intercooler off which is not difficult and get stuck in.
Either get a replacement blanking cap for the righthand (No 1) injector or cut a short piece of pipe and shove something down it like a ball bearing that is a snug fit to blank it off, there is no pressure in these pipes when the engine is running.
Be very careful not to drop anything down the open intake while its off, stuff some clean rag in to prevent it.
Dave
p.s whats this about a glow plug that can't be removed, it can be trying but it can be done and on a ZX isn't that bad, on a Xantia its bad due to ducting and other crap not found on a ZX.
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tomsheppard
- Posts: 1801
- Joined: 19 Dec 2002, 14:46
- Location: United Kingdom
- My Cars:
It is the second glow plug from the left I can't shift. Unfortunately I have rounded a lot of it off. It wasn't particularly difficult to get to - it just appeared to be locked solid.
I haven't a clue how to get it off.
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Dave Burns</i>
Leakoff pipe is available on the gsfcarparts.com web site or just go to your local specialist and ask for leakoff pipe, try and steer clear of the braided fabric covered stuff, it doesn't seem to last to well, the gsf stuff is the real McCoy.
Get enough to do the lot (which isn't much) then take the intercooler off which is not difficult and get stuck in.
Either get a replacement blanking cap for the righthand (No 1) injector or cut a short piece of pipe and shove something down it like a ball bearing that is a snug fit to blank it off, there is no pressure in these pipes when the engine is running.
Be very careful not to drop anything down the open intake while its off, stuff some clean rag in to prevent it.
Dave
p.s whats this about a glow plug that can't be removed, it can be trying but it can be done and on a ZX isn't that bad, on a Xantia its bad due to ducting and other crap not found on a ZX.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I haven't a clue how to get it off.
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Dave Burns</i>
Leakoff pipe is available on the gsfcarparts.com web site or just go to your local specialist and ask for leakoff pipe, try and steer clear of the braided fabric covered stuff, it doesn't seem to last to well, the gsf stuff is the real McCoy.
Get enough to do the lot (which isn't much) then take the intercooler off which is not difficult and get stuck in.
Either get a replacement blanking cap for the righthand (No 1) injector or cut a short piece of pipe and shove something down it like a ball bearing that is a snug fit to blank it off, there is no pressure in these pipes when the engine is running.
Be very careful not to drop anything down the open intake while its off, stuff some clean rag in to prevent it.
Dave
p.s whats this about a glow plug that can't be removed, it can be trying but it can be done and on a ZX isn't that bad, on a Xantia its bad due to ducting and other crap not found on a ZX.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
have you tried shifting it with the engine hot?
I had similar problems with the first head on my BX - the plug didn't look to be in quite properly and wouldn't undo. I got it out by much turning small amounts ech way and it brought out loads of thread with it. Some joker had obviously put a spanner on it straight away rather than screwing it in by hand and then tightening it the last bit with the spanner. Luckily there was just enough thread for it to grip on and it lasted until the gasket went and the head was found to be cracked.
jeremy
I had similar problems with the first head on my BX - the plug didn't look to be in quite properly and wouldn't undo. I got it out by much turning small amounts ech way and it brought out loads of thread with it. Some joker had obviously put a spanner on it straight away rather than screwing it in by hand and then tightening it the last bit with the spanner. Luckily there was just enough thread for it to grip on and it lasted until the gasket went and the head was found to be cracked.
jeremy
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- Location: United Kingdom
- My Cars:
- x 2