Over fuelling

Post by **Vanny** » Fri Aug 10, 2007 4:09 pm

Almost have a 16v again, catch up on the full build story here ;

www.bxproject.co.uk

took it to MOT a few weeks ago and the MOT tester decided that the emissions where too low and took it upon himself to adjust the fueling! Since then i managed to get the car home as it was still warm (failed on minor issues, twisted brake hose, missing wheel bolts) but have been subsequently unable to start the car!

Engine turns over fine, has fuel (albeit not the greatest fuel!) has spark, ecu seems okay. Found out the tester adjusted the biasing potentiometer on the AFM and trying to adjust back to the correct settings totally failed, have subsequently changed the AFM to one which came from a perfectly running car.

Unfortunately i haven't a lot of time to spend on the car at the moment, i've had huge amounts of help from Doc Chevron (pretty much built the car back up) but i'm driving 300+ miles a week and the girlfriend is not happy about me putting the miles on her new ish corsa!

Have also changed the spark plugs (NGK), ht leads (BOSCH Silicone), coil pack thingy (looks like a transformer, swapped a working magnetti marelli one for a Bosch one), there are new jubilee clips on all pipes on the inlet tract including those to the ICV and to the oil breather circuit. When trying to start the car the cylinders/plugs are getting flooded almost within seconds and thus never getting ignited.

I'd be grateful for any and all suggestions as I'm desperate to get the car MOT'd and back on the road!

Timmo · Post by **Timmo** » Fri Aug 10, 2007 4:25 pm

you may have already done it matey but have you checked the earth ont he gearbox?? (box to battery, box to chassis and box to battery clamp) my old 8v 309 earth went and we tired everything! only to find that £5 cable would have sorted it!
may be totally unrelated!

Also, when i built mine back up after the cambelt snapped, i put on a new arm and cap but when the engine had run up to temp it would cut out and wouldnt restart, checked the itming over and over, plugs, then swapped the cap back over with the one that came off th eold head and it was fine!

Post by **Vanny** » Fri Aug 10, 2007 6:30 pm

the cap is a ducellier one that came with the engine (and at least looks to be in good condition) and the problem is that it wont start at all let alone get hot. I do have an intermotor arm and cap but i'm reluctant to fit second rate parts!

As for the earths, lots of care was taken to ensure the earths where looked after (scrubbing the connectors back to shiney and vaselining them up before connection), the clamp is also a good quality aftermarket jobbie with new high capacity low resistance earthing from the clamp to the box. I will however check the earths and make sure there isn't something up with them.

It seems more like the injectors are injecting tto much fuel and leading to the flooding.

AlanS · Post by **AlanS** » Fri Aug 10, 2007 9:06 pm

Last 2 I've had doing this were a TZi and an Mi16 and in both cases it was the pins jamming open, one partially, the other fully, on the injectors.
The BX just ran like sh*t, blew black smoke and then just wouldn't start and the Mi16 went out with a bang and took a liner with it just for good measure.
If one gets as bad as the Mi16 did it could hydrolock although mine just dieselled and then exploded which wasn't good but at least didn't bend any rods.
I'd be whipping the injectors out and getting them to someone who can do a test. I suppose you could do an optical test by spinning it over with the rail out of the car, but be sure you aren't having a puff at the time and the coil is disconnected.

Alan S

csg100 · Post by **csg100** » Fri Aug 10, 2007 10:09 pm

Sounds a bit like my XR4x4 - which was caused by leaking injectors. Definately worth trying some spares if you can get hold of some

Post by **Vanny** » Sat Aug 11, 2007 8:07 am

well that sounds like a nice easy one to try as i have a full set of injectors (i've also got a spare fuel pump and fuel rail and plenty of glass jars so i guess i could test them that way.) The spare injectors have all spent some time in the ultrasonic cleaner so might well get on better that the existing ones.

Just have to get home and try it out (probably on thursday). Does anyone know of an injector specialist in the northwest?

Timmo · Post by **Timmo** » Sat Aug 11, 2007 8:11 am

Vanny, Most lucus shops (lsuk as is now known!) can do ultrasonic cleaning if thats amny help??

martyn · Post by **martyn** » Sat Aug 11, 2007 2:04 pm

Looks like the Liverpool branch has the ASNU cleaning kit.
http://www.lsuk.co.uk/branch.asp

or mail order
http://www.injectorcleaning.co.uk/index.htm

Post by **Vanny** » Sat Aug 11, 2007 3:14 pm

hmmm, Vandaries Street, thats where TaxiFix is down on the docks, know it very well, shouldn't have a problem finding it. I don't have a problem getting access to an ultrasonic bath (i have almost exclusive access to 4 litre one at uni) however there are all the seals and caps to consider. As i have a spare set of injectors i guess getting a set stripped cleaned and rebuilt would be the obvious thing to try, might ask if i can watch. The more i think about it, the more obvious a cause a sticking injector could be so has to be worth a try.

Anonymous · Post by **Anonymous** » Tue Aug 14, 2007 11:07 pm

Sorry to hear that AFM didn't cure it. If you can get car over to me in Burnley on I have a full BX 16v and another AFM. Maybe we can put our heads together and try swapping some bits? I have 27 year's experience of motor mechanicing behind me & a lot of spare time (waiting for a back operation). My 17 years of working on BX's & Citroens (I'm a little rusty brainwise) should mean I can come up with a solution. Or if you can pick me up and run me over to where car is?? Thanks Ian.

docchevron1472 · Post by **docchevron1472** » Wed Aug 15, 2007 12:04 pm

I think I know whats wrong here....
But I shant know for sure till I get a meter on the injector leads....

Are you around this weekend Ian?
Maybe we could all have a massive blitz on Vnaster's motor!

Do or die kinda thing!

Post by **Vanny** » Wed Aug 15, 2007 11:46 pm

i've got a tank of 200 litres of parafin! Pretty sure i can do the 'die' bit!

stupid car

want to give me a clue on this miraculous idea doc>?

docchevron1472 · Post by **docchevron1472** » Thu Aug 16, 2007 1:04 am

It involves a test meter, and "live" duration of the injecters....

AlanS · Post by **AlanS** » Thu Aug 16, 2007 2:12 am

The plugs are properly connected to the injectors I presume?

I've seen heaps who just pushed the plugs on without first lubing in one way or 'tother and the pins push back up inside the plug. Then wonder why all of a sudden they have rough running, intermittent running or no running at all.
A mate of mine rang me from down south a couple of years ago after he's just done a top end job, very concerned at why the engine was stuttering and then stopping, followed by no starting at all; turned out to be this problem and as soon as I mentioned it, the penny dropped with him. He went to the car with the phone still in his hand, relocated all 4, gave it a flick of the switch and away she went.
Regardless of how certain you might be that they are right, give them a check by disconnecting and carefully reconnecting before you get too involved in the technical sh*t.

Alan S

docchevron1472 · Post by **docchevron1472** » Thu Aug 16, 2007 12:33 pm

The injectors are definitley working, they're just MAHOOOSIVELY over fuelling..
Being nearly 200 miles away from the car right now it's not certain, but I'm fairly sure I know whats happening here...

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Over fuelling

Over fuelling