Started the car this (very cold, frosty) morning and after running for several seconds, it stuttered somewhat and cut out, refusing to start again. I may have water or contaminated petrol in the tank, but aside from that, the engine wasn't turning over as quickly as I would have liked.

I swapped out the battery to a newer, heavier duty one and still no joy. I tested both batteries with a digital multimeter and they each showed around 12.05 volts, but when in the car, the gauge on the dash only reads around 9 volts. Might this be an issue when trying to start the car? What would cause such a voltage drop between the battery and the dash?
Can I easily check the voltage at the starter and if so, is there a correct procedure?
Any thoughts most welcome.

 

12.05v is no good, needs to be 12.6v for a fully charged one. Charge one of your batteries for a full 24hrs and then try again.

 

Many thanks for the quick response. Senior moment on my part, but the voltage on the batteries was/is 12.5 and 12.6 volts. My curiosity was aroused only because of my starting issue, which I've nailed down to water in my fuel, which I'd suspected all along.

I undid the fuel line at the fuel rail and the problem is very apparent! So, tomorrow I will be busy pumping, siphoning, clearing etc. and hopefully will get it sorted.

On that note, I'm fine with emptying the tank, clearing the fuel line to the fuel rail, but what's the recommended procedure for clearing out any bad fuel from there to the cylinders, ie. injectors, carb. etc.

Thanks again.

 

I would think that once you've cleaned out the lines and put fresh fuel in the tank it wouldn't take long to fire up. Once running get it nice and warm and then take it for a run.
Don't forget a new fuel filter.

 

Thanks for that. I have a new filter on standby and will pull the plugs and turn the engine to help blow out any unwelcome fuel/water.

 

Sounds like a bad battery. It might put out enough voltage just sitting there, but can't sustain voltage under load when cranking. If it's older than 5 years, I'd replace it.

Can you get gas line antifreeze in Ireland? It's basically pure alcohol, which absorbs any water. Very common here in Canada. I've never had trouble with water in my fuel though, I think that alcohol is added by the refineries as part of winter grade fuel.

I do know the fuel formulations here change from winter to summer. I had a diesel that wouldn't run once as we had a sudden cold snap and it had summer grade diesel in the tank. Once the tank was drained and winter grade diesel put in (less wax) it ran fine.

 

Thanks for the input, but just for clarification, one of the batteries is only a few months old, rated at 110ah, the other is about 9 months old, rated at 100ah. I've overcome any thoughts I'd had regarding their efficiency, after starting the car today. On that note, an update.
The water in my fuel, is real actual water, as opposed to any climatic influence. I had topped up my tank with fuel left in a boat fuel tank, which unfortunately had let water in via the vent, and so, was contaminated. This then finished up in my car.

Today I undid the fuel line at the injector rail and clamped a section of hose onto it, bridged the pump relay and pumped a lot of dirty, watery petrol from the tank. A little tip here, pull the fuses for the fans and you will save your battery from unnecessary drain while pumping out petrol.

Anyway, when the petrol got to the stage where it looked clean, I removed and cleaned the plugs and spun the engine several times (without fuel line connected) just to help clear the cylinders somewhat. Then put everything back together again and after some stuttering attempts, she fired up.

She ran rough and wouldn't idle at first and was pumping a lot of white smoke/steam from the exhaust. To be expected, I thought, especially as it's a cold frosty day here. Eventually, the steam cleared, but still running rough, like as though she's missing on one or more cylinders.

Then I noticed smoke coming from the engine bay and discovered that one of the cats was glowing red hot! I had to use a fire extinguisher (on standby) to douse it and cool it down.

I let everything cool down and tried again, whereupon it started right away, still running rough and soon after the cat started beginning to glow again.

So, any thoughts? What damage might have been done to the cats, and why?

My plan now is to drain the tank fully and start again with totally fresh fuel, but I'd like to remove any other obstacles or issues beforehand.

I have cats on my donor car if needed, so it's not the end of the world, but I don't want to ruin them too!

Any input much appreciated.

 

A catalytic converter glowing means a lot of raw fuel is going through it. Check your plugs, coils and the connection to the coil to make sure everything is correct. It's easy to get the connections to the rear 2 coils mixed up, make sure those are correct.

 

Thanks for that. I've since done some searching and it seems that a misfire will do your cats no good whatsoever. The coils can't really be mixed up as the wires are clipped down and don't allow enough room to get them wrong, plus I've had them off several times before and am always aware of their positions.

I think a total drain and flush is called for, so that's on the agenda for tomorrow. For what it's worth, some pics to show the fuel rail disconnected, with rubber hose attached. I ran the fuel into a clear container to see how it was looking. Also, the fuel pump relay in the boot is shown, with the bridging wire attached, at the " 3 O Clock" position, just for the benefit of anyone else having to drain the tank this way.

Thanks again for the input.

 

A little tip here, pull the fuses for the fans and you will save your battery from unnecessary drain while pumping out petrol.



Here's a tip for future reference. In your 2nd picture, the white plug with the white wire loop is the Jaguar "fix" for the constant running fans. You can just unplug that white plug to cut off the fans when you're tinkering.

I have actually cut the white wire and spliced in a simple rocker switch that I have fitted out of the way under the headlight switch under the dash so that I can simply switch the fans off when desired.


On the subject of the misfire, you will need to check the injectors as water/contaminants may have damaged them if you ran the engine with contaminated fuel and then left it for a while before draining/flushing.