Synerge 1.9TD excess engine noise

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
ebod
Posts: 124
Joined: 11 Dec 2004, 00:38
Location: United Kingdom
My Cars:
Contact:

Synerge 1.9TD excess engine noise

Post by ebod »

Hi All,
My Synergie has recently had a major job done on it ( clutch )and soon after I got it back I've noticed it now seems to have that cold start rattle noise all the time ( well at low gear / light load ).
I have messed about with a cable at the back the pump which was dead slack, and that seems to have calmed the revs done a bit...but obviously thats only a speed control.
I suspect its suffering from the petrol equivilant of running on choke all the time. Can anyone familiar with the late 98 spec 1.9TD engines explain to me where I should be looking and what to check in order to stop this pinking/rattling.
I've posted a pic of my engine bay for guidence.
http://freespace.virgin.net/ian.jarvo/IMG_0014.JPG
Thanks
User avatar
AndersDK
Posts: 6060
Joined: 21 Feb 2003, 04:56
Location: Denmark
My Cars:
x 1

Post by AndersDK »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by ebod</i>

... I have messed about with a cable at the back the pump which was dead slack, and that seems to have calmed the revs done a bit...but obviously thats only a speed control.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
It's exactly what you think - a diesel "choke" device. It alters the roto-pump's fuel injection timing with cold engine - for easier start an less prone to stall with a higher idle rev.
This document is for the common IDI XU diesels : Diesel coldstart device
ScottFromNZ
Posts: 116
Joined: 17 Feb 2004, 09:27
Location: New Zealand
My Cars:

Post by ScottFromNZ »

I had a look at the way my cold start device is hooked up on my BX TZD and it appears to do nothing but increase the idle speed by opening the throttle a bit when cold. It doesn't appear to change pump timing. Maybe some are different to others?
jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00
Location: Hampshire, UK
My Cars:
x 2

Post by jeremy »

Scott - there are at least 2 systems fitted to BX diesels. Originally both Bosch and Roto-Diesel had a cold start evice which simply increased the idling speed at cold. The roto - diesel pump was modified with the introduction of the TD and the pull wire now operates a switch which connects to an electrical unit on the side of the pump which advances the timing. I believe this modification was fitted to very late NA diesel BX and our ZX 1.9D has the same system (1994)
The purpose is to clean up the emmissions and it seems to work well. Amazingly the waxstat device seems to be the same for all!
Not sure when and if the Bosch pump was modified.
jeremy
Dave Burns
Posts: 1915
Joined: 14 May 2001, 05:30
Location: United Kingdom
My Cars:
x 2

Post by Dave Burns »

Almost certainly a timing fault, two things to try that may confirm this, firstly locate the cable coming from the timing solenoid valve towards the bottom rear of the pump, follow it back to its connector (usually brown) and with the engine running unplug it.
Now you should hear an alarming change in the sound of the diesel knock, very loud and metalic sounding, now you know what it sounds like with no electronic timing adjustment reconnect the plug, now with the engine still running unplug the injector lift sensor, if on doing this the diesel knock returns to exactly the same as with the solenoid valve unplugged, this confirms that the TDC sensor is off line for whatever reason, could be unplugged or have damaged wiring or sensor its self is damaged.
This sensor is usually located slightly rearward in the top of the gearbox bellhousing on later models, and because it has to be placed very close to the periphery of the flywheel is easily damaged during gearbox removal/refitting if not careful, idealy it should be removed before box removal to prevent damage.
Note: the middle of the three connectors on the pump goes to the immobiliser, do not disturb it.
Dave
ebod
Posts: 124
Joined: 11 Dec 2004, 00:38
Location: United Kingdom
My Cars:
Contact:

Post by ebod »

[quote]
It's exactly what you think - a diesel "choke" device. It alters the roto-pump's fuel injection timing with cold engine - for easier start an less prone to stall with a higher idle rev.
[quote]
Anders , although I don't have any english Synergie ( called Evasion in the rest of Europe ) manuals to prove it, I think in my case the hidden cable merely allows the speed to increase by maybe 200rpm. By the looks of it, the cable has been slack for a long time and my car has been idling at ~950rpm. Now the cable is adjusted, the idle is 750rpm when warm. Therefore, the timing must be controlled by another device on my pump and your article is not valid for me.
My car is registered in the UK at November 1998 so it is one of the latest 1.9TD designs before the HDI engine was introduced in 99.
ebod
Posts: 124
Joined: 11 Dec 2004, 00:38
Location: United Kingdom
My Cars:
Contact:

Post by ebod »

<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>

Almost certainly a timing fault, two things to try that may confirm this, firstly locate the cable coming from the timing solenoid valve towards the bottom rear of the pump, follow it back to its connector (usually brown) and with the engine running unplug it.
Now you should hear an alarming change in the sound of the diesel knock, very loud and metalic sounding, now you know what it sounds like with no electronic timing adjustment reconnect the plug, now with the engine still running unplug the injector lift sensor, if on doing this the diesel knock returns to exactly the same as with the solenoid valve unplugged, this confirms that the TDC sensor is off line for whatever reason, could be unplugged or have damaged wiring or sensor its self is damaged.
This sensor is usually located slightly rearward in the top of the gearbox bellhousing on later models, and because it has to be placed very close to the periphery of the flywheel is easily damaged during gearbox removal/refitting if not careful, idealy it should be removed before box removal to prevent damage.
Note: the middle of the three connectors on the pump goes to the immobiliser, do not disturb it.
Dave
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Dave, thanks for the reply. Your words do summise what I think is going wrong, but I'm not too sure where the timing solenoid is. Can you use that pic and guide me to it. Also, since the box has just been off, it looks higly likely that the real problem is the TDC sensor.
What can be done if the TDC sensor is faulty :-
1. If its broke, would the engine still be running ?
2. Can it be adjusted?
3. Where precisely should I be looking for it?
Dave Burns
Posts: 1915
Joined: 14 May 2001, 05:30
Location: United Kingdom
My Cars:
x 2

Post by Dave Burns »

This is a typical 1.9td box, look at the two large holes near the ventilation slots, the TDC sensor occupies the one opposit the short slot.
In your picture the solenoid valve is directly behind the bracket supporting the lower fixing of the accelerator (looks like a small shock absorber) lever damper.
Yes the engine will run without the TDC sensor but not properly and no it is not adjustable.
Dave
Image
ebod
Posts: 124
Joined: 11 Dec 2004, 00:38
Location: United Kingdom
My Cars:
Contact:

Post by ebod »

I've had an attempt at tracing through wires and connectors and took a few snaps. I think I've found the TDC sensor but it looks connected okay.
One thing that might explain things is the bloke who did the clutch also took of the flywheel to change the crank seal. I always thought they had a fouling peg fitted ...but wondered if its possible the flywheel is on the wrong position.
Pls check the enclosed pics and help me figure out what the components/connectors are that I've numbered as follows:-
1. Cold start device ?
2. Dunno ?
3. Dunno ?
4. Connector to something underneath pump
5. Connector to item 11
6. Connector to item 3
7. Dunno ?
8. Dunno ?
9. Connector to No2 injector
10. Dunno?
11. Shut-off solenoid ?
12. Dunno?
13. TDC Sensor ?
14. Dunno?
15. Cylinder device on accelerator cable ? what for?
http://freespace.virgin.net/ian.jarvo/top-bay.JPG
http://freespace.virgin.net/ian.jarvo/side-bay.JPG
Many Thanks
IJ
Dave Burns
Posts: 1915
Joined: 14 May 2001, 05:30
Location: United Kingdom
My Cars:
x 2

Post by Dave Burns »

A different gearbox is fitted but the TDC sensor looks to be in the same place.
Forget all the other clobber for a moment, you need to carry out the test that I have described earlier, when its back together again pull plug No.4 (timing solenoid valve) off while its running and note the change in diesel knock, if the car has a rev counter also note if it stops reading with this unplugged.
Plug No.4 back in and unplug No.9, if the heavy diesel knock returns as with No.4 unplugged, and if fitted the rev counter stops then you need to concentrate all your effort into finding out why the TDC sensor is not working.
Come back with the results of these tests.
Dave
ebod
Posts: 124
Joined: 11 Dec 2004, 00:38
Location: United Kingdom
My Cars:
Contact:

Post by ebod »

Doh..the wifes gone out and took the keys for the car so I can't look tonight.
All this about the TDC and rev counter does bring back a few bad memories during a holiday in France this summer. We took the car to the Vendee and it started playing up in the hot weather. It wouldn't start and occasionally the ecu light flickered on. Then we made it back to the UK and the problem disappeared, but for a 3wk period the rev counter died, then its been okay since September. I'm starting to think this clutch change has disturbed an old bug.
Anyway, I'll do this no4 ~& no9 plug check through the week and revert to this post.
Ta
ScottFromNZ
Posts: 116
Joined: 17 Feb 2004, 09:27
Location: New Zealand
My Cars:

Post by ScottFromNZ »

I have had another look at my BX TD pump and it actually appears to have two devices for cold start.
1. The much talked about "waxstat" device which joins the thermostat housing to the rear of the pump via a cable - this appears only to adjust the throttle and hence idle speed.
2. At the front of the pump is another coolant actuated device connected by a short cable to a lever on the front of the pump which looks like it may change the pump timing?
What I noticed with the engine hot is that this front one was not returning against the stop all the way and the cable was not loose either. I have adjusted the cable slightly so that when hot the lever just touches the stop. I suspect that this device on the front which I assume advances the timing when cold may not be releasing all the way when hot. I will check the clearance between the lever and it's stop later when it has all cooled down to see if the position has changed.
ebod
Posts: 124
Joined: 11 Dec 2004, 00:38
Location: United Kingdom
My Cars:
Contact:

Post by ebod »

...okay, I got a chance to look at it tonight.
I just pulled plug no4 when luke warm ( advance solenoid ) and it went even more rattly....the rev counter kept going but the engine management light came on.
After plugging no4 back in , I then pulled the plug on the top of the pump to the injector ( no9 ) but nothing noticeable happened and the rev counter stayed on.
So I'm guessing that the advance solenoid is okay but somehow recent the clutch change had affected the TDC sensor.
Please advise a next step..
Thanks
NiSk
Posts: 1422
Joined: 24 Jan 2002, 20:11
Location: Sweden
My Cars:
x 1

Post by NiSk »

Seems the nerds who changed the clutch must have wacked the TDC sensor or knocked it out of line. Either get them to fix it or do it yourself. I guess you could check the continuity of the signal from the sensor (stick a DVM across it on AC mV) and see if you have a signal. Or even something as simple as just pulling it out and checking if it looks damaged. I had a similar problem with my first XM (petrol) a bit of swarf from manufacture got dislodged, swung round with the flywheel and knicked off a corner of the sensor = no start. So they are sensitive.
//NiSk
ebod
Posts: 124
Joined: 11 Dec 2004, 00:38
Location: United Kingdom
My Cars:
Contact:

Post by ebod »

Okay, so please explain how this thing works if its a single M6 screw holding it on. There doesn't appear to be an adjustment of any kind.
How does the TDC unit work ? Is it reading light / ultrasonic / magnetic ? How can it be adjusted ?
..and finally, how does it effect the timing of my fueling ? If the car was common rail electronic injection I could understand, but how does it interact with a Bosch mechanical IDI diesel pump ?
Post Reply