V6 Running Problem., starts but......

[carlos774]

Hello again, Finally got the XM out of the field and drove it back here. The car actually ran for about seven or so minutes before it stopped again. So possibly the petrol filter ..... ?. Which brings me to the next point. I've cast the runes , and sacrificed a small creature to the Design Gods of Gaul, rattled any number of chicken bones but so far enlightenment is not forthcoming.....
So can anyone on the forum tell me, is it really the case that half the car has to be dismantled to get at the fuel filter, and even more taken apart to change the thing .
I can barely get a hand to the strap much less actually do anything with it....... !
Or maybe a hole cutter could be useful on the boot floor???
Any advice gratefully recieved
Cheers Carl.

[UFO]

I have found that to give a little more access to the filter, it is best to drop the spare tyre cage out of the way. It gives your arms better access. You will more than likely get splashed with petrol anyway.

A couple of other things you could check:

Is the fuel pump providing pressure? Could be a dud pump.

Is the fuel stale? If the car has been sitting for a long time it might be off.

Is the ICM (Ign Control Module) gone to meet its electronic gods? The ICM in a V6 12v sits on an aluminium panel (its heatsink) in the side of the battery frame. The thermal paste can disappear meaning the ICM becomes overheated. First test is to get some new thermal paste (local electronics shop) and remove the the ICM, clean away the old paste and apply some new paste and reattach the ICM.

Better still if someone nearby has a similar car, see if you can do a swap. If there's runs your car OK and yours fails in their car, you have the solution.

Just my few cents worth.

[DerekW]

I would support Craig's suggestion that the ignition control module is at fault. These are similar to the symptoms that I had on two 2.0 XMs. The first one never actually stopped but went on the miss and lost most of its power - I never did solve it. The second one left me stranded on two occasions. Following advice fron the rescue service I changed coils, plugs and ignition leads and it let me down again. This time I tried to start it after 20 minutes or so and it started and ran perfectly, to stop dead again a couple of miles nearer home - and again - and again.... I changed the module and problem solved.

A couple of years later my wife's then Pug 309 had the same symptoms and change of module cured that too. Fortunately they aren't too expensive.

Derek

[Auckland Al]

good morning team - had the same problem a few weeks ago. It appeared to be a fault in the start from cold fuel delivery ( choke in 1960's terms) I found that the car was OK until running temp reached and then cutting out until cold with the same start up run cycle!!!! This implies that the fuel delivery change from a rich mix to normal when the engine heated up was not happening - yes the engine is OK now - the remedy didn't find one but I persisted with starting up etc., along with "tapping" the injectors with a small spanner and cleaning all electrical connectins arond the engine the fuel delivery eventually righted itself!!!

ABSOLUTE ROCKET SCIENCE!!!!!!!

Incidentally I had a similar issue with the ignition amplifier and had it replaced by the local Citroen garage - I am almost positive that your problem is not an ignition one as the car does not run long enough to heat the unit enough to fail

regards Alan

P.S. didn't them All Blacks do well

[carlos774]

Good Morning All.
Dropped the spare wheel cage off ,much improved access ,struggling to get the front pipe clip off but I'll beat the little **** in the end. I'll pick up a filter in the week now I know which one it is .(the guy had two listed for V6 and one was a lot smaller than the other) Once I get the new filter on I'll see what pump pressure is like and post again.
Many thanks for the help so far everyone.
Cheers Carl.

[carlos774]

Hello again , just as a matter of interest ....what sort of pressure should the petrol pump be giving ?. I only have access to the 'finger over the pipe' method of testing at the moment . So, on a scale of easy to stop, hard to stop, or ****** impossible to stop , or, oh lor' I'm drowning !!. Where should I be?.
If this isn't the best way to do the check .......... What should the pump deliver?
Cheers, Carl.

[carlos774]

Hello again,
Changed fuel filter and the symptoms have changed a little. The car now starts very easily, comes in on six immediately instead of lighting up on two or three then working upto six. It will run now for a longer period of time (around 15 minutes or so) then, as before it simply stops. I held it steady on 1800 revs for a while and noticed that just before it stopped the revs picked up very briefly by about 200 rpm . Mixture leaning out as it starved maybe ?.Can it do that with injection?. Could I be looking at a relay or pump fault ?
Over to you ............
Thankyou all for the assistance thus far.
Carl

[Jan-hendrik]

Isn't it time to have the fault codes read out? But I bet it's the ignition

[carlos774]

Hi Jan , tried the codes earlier and it wasn't showing anything.
If it was the ignition module would it not feel hot to the touch,assuming it was not losing heat through the sink plate ? . I tried for a sparks after it had stopped on one of the previous occasions and got a reasonable result. Though, to be fair I have seen better on other motors in the past. When it does start to die if I attempt to blip the throttle to keep it running it feels much like a major 'flat spot' on a carb engine with a bit of 'popping' as it dies anyway.......
It's possible that I might get access to a code reader in a couple of weeks but till then........

Cheers, Carl

[carlos774]

Hi Everyone ,
O.K. Got fed up fiddlin' and faffin' about and tried the Aukland Al school of mechanicin'.
Now, got the old beast up to around 3000. 3500 rpm and just kept it there. The motor lost 500 to 1000 rpm a couple of times but I was able to pick it up on the throttle where I think on low rpm it would have died. So, after that I just left it to tickover for probably 15 minutes or so and it never faltered. Did the same the next day and it only lost 500 or so rpm once . today I went and started it up and with no throttle, it ticked over for 35 minutes and never faltered once. Turned it off, had a coffee and took it for a run 15 kilometers or so with absolutely no problem with the engine whatsoever. It ran sweet as a nut, clean as a whistle right through the rev range in any intermediate gear and rather well at illegal speeds in top.
The only thing I found was that the ride seemed a bit hard and there was a graunchy sound seemed to come from the rightside footwell area when driving with a bit of steering lock on.
So something else to investigate.
Thanks to everyone for the help and advice, and, if anyone has any idea what the problem might have been with the engine I'd love to know.

[techmanagain]

Dirty plugs?
Patially blocked injector?
Clogged silencer (LOL)

[demag]

Isn't it a fact that these modern unleaded fuels "go off" quite quickly? They go waxy I think if left for a while and dry out like a laquer. I know they can completely clog a carb if not drained and cleaned. Pampered bike engines are a classic case when they only have light(ish) summer use. If not drained properly for the winter lay up they can be a nightmare to get going in the spring.

So possibly a combination of old filter and waxed injectors? Maybe the new filter and extra revs managed to break down the deposits and blast them through the injectors.