Problem with Cx

I have a 1984 CX2500IE pallas auto.
I have been having an intermmitant fault for several months which has eluded my fixing.
I get the motor cutting out. It does not miss fire. It can occur at any speed and at any temperature and even when the car is idling.
Sometimes the motor will cutout then continue running or it will stop all together which means pulling over and it usually restarts immediatley.
I have replaced ignition pickups, most of the relays involved in ignition or fuel management. I have cleaned and tightened ever connector in the engine bay. I have removed both injection and ignition ECU'S.
I have pulled and twisted ever cable that I can get my hands around and I still can't get the beast to cut out.
I have tried disconnecting plugs while it is running and it may stop completely or just continue running but roughtly but not stop and then continue.
Has anyone had a similar problem and found the cure.
My car has key operated central locking. Does this system include an engine imobiliser. I am guessing that this may be faulty but do not know if or where this is mounted.
I have traced the fuel pump wiring but this is OK.
If I disconnect the fuel pump power feed the motor justs slows down until it runs out of fuel. Not the sudden cutout I am experiencing.
Any ideas Please would be greatly appreciated

Hi Vince,

have you tried cleaning the connections to big blue?? Try wiggling the connector to this relay. If you suspect it may be the fuel pump, hot wire it & go for a drive. If the problem still happens clean the earth to the fuel pump, if it still happens, the power feed to your fuel pump isn't the problem.

Sounds like your having fun anyway roll_lau roll_lau this sort of stuff is enough to drive you to a_drink a_drink

seeya,
Shane L.

AFAIK the central locking doesn't connect to an immobiliser - certainly on my key operated 81 model it doesn't.
This may be a really silly question, coz I can't remember if anyone asked or you commented about this on the CX board, but have you had a look at your concertina to the air filter? Usually a hole in this will only make the car cut out when the motor moves sufficiently (eg changing gear).
Again, I wish you well.

Hi
Thanks for the replies.
I have replaced the blue relay for the fuel pump/injection system.
I have traced the wiring all the way back to the pump and found no breaks.
I located the pump power lead connector under the centre console.
If I disconnected this lead with the motor running all that happened was that the motor slowed down as the fuel pressure dropped until it ran out of fuel.
This is different from the sudden cutout I am experiencing.
I have also taken every connector apart and cleaned and tightened each one as well as recrimping the wires to the spade contacts.
Today I went for a long drive and it cutout then continued running about 4Kms form home and ran without cutting out again for the rest of the trip.
Regards
Vince

Hi
The concertina is not split.
I have even pulled the cover off the air flow sensor and cleaned the potentiometer contacts.
No change.
Regards
Vince

Vince,

I have had this problem not on a Cit but on other vehicles.
How many keys do you keep on your keyring? If it looks like a jailer, get rid of them all bar the ignition key & see what happens. I have seen the weight of a bunch of keys or emblems cause the problem. Even if you don't have a big bunch, there's a chance that someone in the past may have and this has created the problem you now have as it tends to cause the lock part of the key to not run true on the electrical contacts in the rear. It used to be a fairly common problem in used car yards.

Alan S

Vince,

Had a very similar symptom on a CX 2500iE Prestige I once owned. I'd have a very close look at the fly wheel ignition sensors and/or at the points on the flywheel these sensors read. Replace the sensors and thoroughly clean the contacts they read from.

Extracts from useful site

<a href="http://w1.840.telia.com/~u84003985/CITROEN/CXTANDKOND.HTM" target="_blank">Mekartips CX 25</a> Worth a bookmark wink

Frank (NL): The purpose of the mentioned sensors is as follows: The initial ignition timing is determined by the synchronization sensors, which are mounted close to the flywheel. one sensor responds to the passage of a slug fixed to the flywheel at the static or idle firing point for cylinders 1 and 4. The second sensor detects engine speed by the speed of the starter ring gear teeth passing it: this information is used by the computer to determine speed-related (centrifugal) advance. On 1987 models year vehicles there is only one dual function sensor, which picks up from a datum tooth on the starter ring. The vacuum sensor enables the computer to read inlet manifold vacuum and make an appropriate correction to the ignition timing.

Bob R: Right you are, Alan. As usual, I dropped a word in my last post. I meant to say that the initial failure mode is SOMETIMES a short! For those suffering with a car that likes to cut out or otherwise misbehave, take note! The most common causes of ignition misbehaviour on a CX are cross-talk between the leads to the coils and the flywheel pickups, and RF interference from improper (very low resistance) spark plug wires. If you have a problem after ensuring that these issues have been resolved, remove the ignition computer and open the case to inspect the circuit board. We have seen one that had significant damage to the printed circuit.

Cheers
Chris

Hi All
I did a long trip yesterday and the car ran fine with no cutting out.
I did a second trip and on the way home it cut out.
I stopped and it took 3 tries with the key to get it going again. Did not miss a beat for the rest of the trip.
Still trying to find cause.
regardfs
Vince

I still don't think a bookie would give you odds on it not being related to the ignition switch.

Alan S

Alan S:
I still don't think a bookie would give you odds on it not being related to the ignition switch.

Alan S

Click to expand...

My money is still on the the ignition pickups or leads wink
As quoted above....
"For those suffering with a car that likes to cut out or otherwise misbehave, take note! The most common causes of ignition misbehaviour on a CX (fuel injected) are cross-talk between the leads to the coils and the flywheel pickups"

My car would behave just as Vince describes his, it might be good for three or four days and drop out on the next drive, good for a 100k or so and drop out again no rhyme or reason. Once the pick-ups were replaced the symptom never reappeared.

Cheers
Chris

Just a quicky as I'm passing through.
Had problems with the c-matic the other day. I lost the ability to put into or change gears as well as the intermittent starting problem becoming terminal & it just wouldn't start at all.
As it was always going to be a two man job, I have just parked the car up until I could arrange for the second set of eyes & hands to get on the job. I was thoroughly convinced that it had to be related as both were total power losses & whilst I'd lived with & worked around the intermittent starting, it went totally dead at the same time as the gears went walkabout.
It happened tonight & for the record, we found a relay that had got water in it & was badly corroded; that fixed the gears up & after much weaping & wailing & gnashing of teeth, discovered that the back of the ignition switch had partially moved & was not connecting properly internally. Removed & refitted it is now working like a top. Just thought I'd toss this in to show how even those aware of this problem can still be caught out with it.
Incidentally, this was sheer coincidence not accident by design
So the big blue beast is back on the road...you beauty!!
Could I ad something to Chris's suggestion? Check the actual leads to these sensors also as it is quite common for CX wiring to go absolutely rotten internally & this will cause problems exactly like a sensor or item connected to these wires behaving as though the actual component had failed.

Alan S

<small>[ 03 March 2003, 11:21 PM: Message edited by: Alan S ]</small>

Hi
I checked the ignition switch and found no problem.
Yesterday when I drove the car it was fine when I left home but it got worese as I drive it.
It would not accelerate from start and ran roughly.
Once moving it went OK.
I fitted a new set of spark plugs.
When I removed the extensions from the plugs one of the plug terminals unscrewed with the extension. This must have been a faulty plug causing the problem.
The car did not cutout once even with this problem.
Need to drive some more to see if cutout problem recurs.
Regards
Vince
Z