Hi all

I saw a couple of threads already describing similar issues to mine but none of it were exactly the same so I thought I'd post my own

I have had a 2010 1.6 petrol/LPG Focus (I'm in Italy, so the LPG system was added from the factory, it's not an aftermarket kit) for about 10 months and, except for June-August, when the temperature basically never falls below 24°C, has a very long crank if you let it sit for more than 6-8 hours I have to hold the power button for at least 5-6 seconds of continuous cranking to get it started, instead of the usual half a second. I've noticed that it happens more when the temperature when I start it is significantly lower than when I turned it off.

I tried to do a bit of troubleshooting myself, I replaced the LPG ECU because it had issues which are now fixed, but it wasn't the cause for this. Last year I drove on petrol only, with the LPG system completely turned off, for about a month, and it would still do this, so I'd definitely rule it out.

I also swapped out the 60Ah, 540CCA battery that came with it with a 72Ah, 680CCA Varta battery, thinking I had something draining it too much, still no difference in the cranking time.

I also tried, instead of the usual "press the button - wait for the lights to go out - press the clutch - start the car" routine, just pressing the button (basically the equivalent of turning the key to ACC) 3-4 times to prime the fuel pump, because I read around the forums that that might be the problem, but it still cranks long. Pressing the throttle while it cranks also makes no difference.

It has never failed to start, it just takes longer, and once it starts it has no problems idling regularly and it runs perfectly, so I'm not that worried, but it's still pretty annoying so I'm wondering if any of you has got a similar issue? Can you suggest anything else I can check? I'm not really in the mood of throwing money at it until we find the problem but if there are any simple checks to do I'd love to know them.

Thanks in advance!

I had a very similar long term problem on one of my previous non Ford cars. Long crank then started up and ran fine.

After checking that it was actually sparking at the plugs, I finally pinned it down to leaking petrol fuel injectors.

I removed the fuel rail and injectors and had the complete assembly set on top of the engine. Primed the fuel system to have pressure in the system. It didn't take long to spot the one which was dripping petrol.

You could still have this problem with no actual drip being visible, since the leak could be small enough to dry up before forming a complete drop. Indeed 2 other injectors in my rail were visibly wet only.

I don't know how your LPG system works but you could have a gas leak when the engine is shut down giving the same start up problems.

Let us know how you get on.

ScaniaPBman.

 

2 minutes ago, ScaniaPBman said:

I don't know how your LPG system works but you could have a gas leak when the engine is shut down giving the same start up problems.

 

I have owned (and very much enjoyed) an LPG car. When cold, the car starts automatically on petrol, it's only when it gets up to temperature that the LPG system will seamlessly kick in, so I would doubt very much if it had any effect on the long starting crank.

It could be a failing crankshaft sensor.

Ok so I'm resurrecting this thread after nearly a year because it looks like I might've finally figured out what the problem was!

(TLDR at the end)

A couple months ago, while running on LPG, my car threw a CEL because of a misfire in cylinder 2, so I swapped injectors 2 and 3 around to see if that was the problem

Note that the car was running pretty fine, or as well as it'd ever ran whilst in my possession, so I didn't make much of it

Come early September, morning temperatures started falling back below 20°C, so the long crank problem came back, but I decided I wasn't gonna change every single component hoping that would fix that, so I just lived with it.

Since the CEL I ran another couple months trouble-free until, a couple weeks ago, after filling up on LPG, the car started stuttering horribly and flashing the CEL which I'd never seen, so I tried running on petrol and it worked flawlessly, as usual.

I checked the OBD for errors and, lo and behold, cylinder 3 was misfiring this time around.

I changed that LPG injector and, besides fixing that awful stuttering, and improving my mileage by quite a bit (I was getting about 40% worse mileage compared to petrol, now it's around 15-20% worse, which is to be expected) it seems to have fixed the lonk crank too!

TLDR: One of the LPG injectors was probably leaking since before I got the car, until it completely stopped working and got swapped out for a new one that the problem got (apparently, fingers crossed) fixed!

 

Now, these LPG injectors are usually rated for around 100-150k Km before they need replacing, my car currently has 170k and it doesn't say anywhere whether they've already been replaced before or not, the previous owner didn't write down any maintenance whatsoever, even the timing belt was replaced and there was no trace of it, so I wouldn't be surprised if they aren't the ones that came out of the factory along with the car.

I'll keep an eye on the situation and I'll update the thread if, once temperatures fall down to around 0 the problem shows up again, but, for now, I'm pretty satisfied with this!