BX16V.com Forum

Hello chaps,

after my 4 figure repair bill, the BX has been sat outside.

Started fine on Tuesday, not taken out anywhere, but started perfecty.

Yesterday evening, Darren was going to take her over to Southend, but she would not start.

Battery is fine, was turning very healthily, but only coughing now and then, if about half throttle was applied.

Tried starting with full throttle, and then pumping it, but no joy.

We then tried GT85'ing everything, dizzy cap, proved the dizzy cap was working fine, and giving a good spark, also checked two of the 4 leads were giving a good healthy spark, and no probs.

Fuel is low, but the warning light is not on, and although it is not fresh fuel, it is not super old or anything.

Tried it again this morning, as thought it may well have flooded, but still the same, bit of a cough, but not really that close to catching.

Oh yeh, took the fuel pipe off as well, and proved fuel was coming out with plenty of force.

Anyone got any bright ideas?

Cheers

Dan

Two of my valvers have done this.

The first one had a problem with one of the fuel injection relays bolted onto the wing near the LHM reservoir. I cant remember what exactly it was called but it wasnt a regular relay though it looked like one. This one also used to cut out for no apparent reason at inopportune times, like when idling in a queue, and would fire back up again shortly after running out of curse words and phoning the RAC for a recovery.

Second valver refused to start, had good spark, fuel, fully charged battery, and the garage said it was spark plugs being old and manky.

Hi Rich,

thanks for the reply,

spark plugs might well be the next port of call.

Question for the techies out there, can anyone tell me if there is a specific sparkplug tool I need to buy, and also does it need an extension arm or something, I seem to remember they are a long way down....?

Anyone recommend an online retailer for this?

EDIT: Looking on ebay can see several offerings, of different sizes, anyone know what size I would need for the plugs in the BX?

How about this for example:
http://cgi.ebay.co.uk/16MM-FLEXIBLE-SPA ... 4153b805cd

Or this one - not quite seeing how this one works I must be honest:http://cgi.ebay.co.uk/Sealey-VS1591-Spa ... 1c16894eb3

Or how about this?
http://cgi.ebay.co.uk/1746-LASER-TOOLS- ... 3cb12cbd8a

Cheers

Dan

hi dan, spark plug i'm sure is a 16mm type. the plugs do sit deep so a 5" extension will be needed on your ratchet to get them out. you can get the correct bx 16v spark plugs on ebay for a good price, better than halfords etc. from my experience these cars get flooded very easily which causes big problems is its a slow starter. also these cars need a v strong v bright blue spark. i have had issues before where i have been chasing my tail for ages trying to get mine to start. i had fuel and what looked like a good spark, but it turned out the spark wasn't good enough and i needed a new coil after being sure for weeks it wasn't a spark issue. in my experience they are more particular about the spark they get more than anything else.

rossco

i use a 16mm plug socket and extension bar for mine although do have the t handled one as per the first link and can confirm they do work!!

when mine wouldnt start i charged up the battery as flattened it trying, took plugs out and cleaned them up one by one, then cleaned dizzy cap inside, scraping any cack off the electrodes, and same for rotor arm,
fired up a treat then!

the sealey tool iirc it a metal bar with a big rubber bush type inside which plugs onto the top of the plug, the tip is 'when loose' on the ad!

did you mean wd40 not gt85?? gt85's silicone based!

GT85's teflon based but it'd still do the trick. Personally it's spray on copper grease or totally dry (and clean) for me.

Is the fuel actually getting supplied to the cylinders? You've got it at the rail but is it getting injected? Download the PDF from this site and attack the ECU pins with a multi-meter to check for the obvious things.
You've got a fuel pump relay, which is obviously fine, but you've got the injection relay too which controls the firing of the injectors. They batch fire, so all at the same time. You can check the feeds to and from this using the PDF file.

Give the battery a full drop charge too....on some cars (like mine recently!) the starter draws such a current if the engine has improved earthing that the amp doesn't get a strong enough signal from the CPS (normally a weak battery, like 12.2v is noticable by slow turning on the starter, but this is usually only cars with tiny batteries or crap earths). This in turn was recieved as a weak signal at the coil. It did spark in atmosphere (plugs find it easier to spark when they're in clean air than under compression) but it didn't start until I charged the battery and used a timing gun to check I actually had a spark with the plugs in situ. Before the battery was charged it was just flooding. It was also only sending 8v to the pump, which was a tell-tell sign.

But run through that PDF, and download the CAPs demo too if you haven't already. It's invaluable to have a copy and top marks to Luke for it being there!

I once had a similar problem, good spark, good fuel supply, fully charged battery but it just wouldn't start. It would try now and then but wouldn't keep going. It turned out to be the Crank Angle Sensor (CAS), which is an inductive pick up sensor fitted in the top of the clutch bellhousing. It gives a reference to the ECU so it knows when to trigger the coil and give correct ignition timing.

Yeah that happened to mine, wouldnt start and just coughted and spluttered turned out to be the crank sensor.If the clutch is getting towards the end of its life and a lot of dust and fibre has been released from it,Then a lot seems to collect on the crank sensor aswell as everwhere else in the bellhousing causing a break in the magnetic signal to ecu causing starting problems.
Soulution is to simply clean the face and put it back in,although you will need to remove the HP pump and bracket to do it.