Citroen ZX - Please Help

c_k_b_69 · Unread post by **c_k_b_69** » 29 Nov 2003, 07:16

Hi all,
This board seems like a godsend to me. I love my ZX more than I loved my old AX, there just isn't a car quite like it. It was £675 well spent. However ever since I bought it, it hasn't been without it's problems. I've searched to board for soloutions but to no avail. They go as follow:
1.Clock only lights up when it wants to (not very often)
2.Passenger side cental locking only works when it wants to on both doors.
3.Sometimes the engine stalls when idle
But the biggest problem is the engine misfires and backfires regularly. It seems to always backfire at 3000rpm. And very recently the Engine Diagnostic light has come on.
Phew!
Any advice would be appriciated. I understand the best thing to do would be to take it too a dealer, but they'd probably charge more than the car is worth, so i'd prefer a DIY soloution if possible.
Many Thanks,
Colin

AndersDK · Unread post by **AndersDK** » 29 Nov 2003, 09:23

Colin -
I'd say your ZX problems are normal & simple service issues - as you may find on any other car with some years on the wheels.
1) Sounds like the bulb needs replacing - or the bulb holder or associated wiring has an intermittent connection.
2) Similar problem - but no bulbs of course. Cable/connector problem - in more severe cases one or both of the involved doors may have to be stripped for conclusion of the problem. Often one of the wires running in the door-to-pillar bellow is sheared/chafed.
3) Well - the engine management ECU has finally lost patience with your lack of service hours and the frequent stalling problem - and is now signalling a consistent problem somewhere - thus giving you the light [:(]
I'd start with the usual basic & common service issues : plugs, plug HT cables, air filter, any vacuum hoses for tightness etc etc.
If you do not allready have the Haynes ZX workshop manual - it's definately high time - as pages & pages could then be written here explaining details - without you having a clue [8)]
It's a cheap DIY must-have-item and available right here : www.gsfcarparts.com

c_k_b_69 · Unread post by **c_k_b_69** » 29 Nov 2003, 16:04

Thanks for the speedy reply,
I only purchased the car 6/7 months ago, and the guy said the car had been seviced recently. I took a look at the ecu this morning, it looked brand new. No dust on it, labels still fine.
I also took a look at the distributer this morning. Am I right in saying there is no high voltage wire running from the ECU to the distributer, which means the ignition coil and distributer are housed in the same component? Once again this looks like it may have been replaced, it's manufactured by Bosch, is that the factory fitted original?
Colin

Sl4yer · Unread post by **Sl4yer** » 29 Nov 2003, 20:43

It probably won't have a distributor as such. What model and age is it?

c_k_b_69 · Unread post by **c_k_b_69** » 30 Nov 2003, 02:26

1991 ZX Aura 1.6i Cat.

Sl4yer · Unread post by **Sl4yer** » 30 Nov 2003, 19:41

The 1.6i engines have a Magneti Marelli system according to Haynes, so I'd be surprised if the coil was made by Bosch.
Try the things Anders suggested (these are quick DIY jobs anyway) and check for loose connections around the engine. If that doesn't improve things, you will need to get it looked at by a specialist (not necessarily a Cit dealer). My local garage is a Bosch dealer, so they can test, supply and fit parts much cheaper that the Cit dealer. Try to find a Magneti Marelli specialist or even just an ignition specialist in your area. It shouldn't cost the earth to get a diagnostic check done.
There is some information relating to the system (albeit on a BX, looks like the Haynes manual) here: http://www.renaultfaq.ru/download/magnetti.pdf

oscarloco · Unread post by **oscarloco** » 01 Dec 2003, 02:21

About your car stalling, you should replace the idle step motor. It is a little expensive but it is the only cure for the stalling.

Sl4yer · Unread post by **Sl4yer** » 01 Dec 2003, 03:36

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

About your car stalling, you should replace the idle step motor. It is a little expensive but it is the only cure for the stalling.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I understand what you are saying (my stepper motor failed this year), but there are many other possible reasons for the problems described. If the stalling problem was from starting cold, or at a particular temperature range, I would suspect the stepper motor. But with everything else I don't think its the problem.

c_k_b_69 · Unread post by **c_k_b_69** » 16 Dec 2003, 04:25

Thanks for all your help so far, the problem however remains...
Update:
Took the car to an ECU specalist- Firstly they adjusted the fuel/air ratio as it was running lean when idle, since then I haven't stalled at all.
They also cleared the faults from the ECU, however one remains which is the Air temperature sensor, which needs replacing. They think the car isn't misfiring, instead it's the fuel injectors which just cut out at 3000rpm, but only when a load is applied (i.e when in gear). They think the cause is a faulty map sensor. (Without sounding too stupid I hope!) What is a map sensor and what does it do? Is it cheap to repair/replace?
And why 3000rpm?! The only thing I know that is special at 3000rpm is that that the engine speed that produce the maximum torque. Is there anything else special about it?
Thanks,
Colin

lhm_leak · Unread post by **lhm_leak** » 16 Dec 2003, 04:48

I'd look carefully at the idle speed control motor and its associated gubbins. Not sure about the ZX, but problems on other cars I've worked on with similar faults and diagnostic reports have turned out to be due to muck in the control mechanism, or dodgy gaskets/seals and even stripped bolts!
To answer your question, a MAP sensor is a "Manifold Absolute Pressure" sensor, and it does exactly what it says on the tin, i.e. measures the absolute pressure in the air intake. (Absolute pressure is a value with reference to a vacuum, as opposed to Gauge pressure, relative to atmospheric.)
You won't be able to repair it - unless you have a split pipe leading to the sensor. Don't know about replacement costs, but they should be cheaper than the old mass airflow meters!
Stu.

danny · Unread post by **danny** » 17 Dec 2003, 04:05

Buy the diesel version. less hassle, lol

wheeler · Unread post by **wheeler** » 17 Dec 2003, 04:57

check for oil in the small pipe that goes into the MAP sensor or in the sensor its self.if there is oil in the pipe you may have to modify its position so the sensor sits up higher.

Stuart McB · Unread post by **Stuart McB** » 18 Dec 2003, 00:53

Aha. MAP sensor my forte. They cost an arm and a leg but you can get the price down to £65 by buying direct from Bosch. Easyiest repair ever. When found remove the sensor from the vehicle carfully remove the small bore pipe that runs to it and clean by passing carb cleaener or white spirt through it. This removes any trace of oil. Now place your MAP sensor on a radiator over night with the heating on but place some paper towel under it so as to catch any oil that's lurking in side. In the morning if it's oil contamination of the MAP sensor there should be oil on the paper towel. Clean and refit. The Vehicle should now work OK. This pesky little unit was the cause of 5 yes 5 trips back to the dealer until he gave up looking there were no fault codes nothing. A mate who worked for Vauxhall mentioned it to me and hey presto done as above no problem ever again. What happens is oil vapours eventually turn to liquid and settle in the unit / sensor and block the little rubber diaphram in it this then send a signal to the ECU telling it that there's either to much or not enough vacume at the manifiold and hence rough ideling, stalling & too rich a mixture. To combat the oil entering fit one of though cheap petrol filters from you local motor factors they cost about £2 in to to the plastic pie leading to the sensor.