V50 Engine 2.0D : Wouldn't start - now does but only 2 cylinders!

[rich_f]

Hi all,

I have a serious problem with my 2006 v50 2.0D and am in need of help.

A few weeks ago I went to start it and it wouldn't fire up. I noticed that there was a large air pocket in the clear fuel line coming out of the filter housing. I don't know how it got there but I assumed it was because I hadn't driven the car for a few days (though I have left it much longer periods recently without issue).

Anyway I bought a priming pump and a new fuel filter too as I thought I might as well change that since there's already air in the line. I changed the filter and eventually, after a lot of squeezing, got all the air out of the system (well as far as I can tell). Tried starting - still wouldn't fire up.

Loosened off the fuel lines to the injectors to see if I was getting fuel - there was fuel.

Took one of the electrical connections off an injector to check it was getting power while my wife cranked the engine - it started! On 3 cylinders though so I quickly plugged the injector cable back on but it continued to sound the same - very lumpy and would not rev past 1200 rpm.

Thought maybe since I plugged it in while running it didn't detect the injector or something so turned off and back on - same. Running on 3 cylinders and could feel 3 cylinders 'clicking' when I put my finger on them but the one I had unplugged earlier wasn't.

I read some people have had issues with the egr valve so I decided to take off the pipe and plug the hole to see if it made any difference and it didn't.

I took the anti-run valve out of the inlet manifold and cleaned and filed it's edges as some suggest and that made no difference.

I then decided to disconnect a different injector and see if the one that wasn't working sprang back into life - it didn't, and now the car was running on 2 cylinders and even lumpier than before so I plugged the connector back on and... It didn't do anything. It was still running on 2 cylinders. Turned the engine off and started again - still 2 cylinders.

So it seems like I killed 2 injectors by unplugging them and plugging them back in. Does this sound right? Have I fried some circuitry somehow? I thought maybe if I disconnect the battery and connected the leads together I might be able to reset something in case it was in some protective mode but it made no difference (and I don't know if doing this works on this car anyway - works on my wife's Nissan to clear things)

So what have I done to my car? Any ideas? I have a cheap obd reader but it doesn't come up with any codes. Are there any members in the Salisbury area with something that will read any fault codes it might have?

[IainG]

Hi
Worth at least trying a battery reset again before you go further.
Disconnect your battery for a while (30 mins) and see if that will reset the ECM/injectors. I think that shorting the leads doesn't always reset modules, I believe the modules need time for the internal circuitry to self discharge, to reset.
If you carry on as you are you may just compound any issues. You need to get the injectors working before you go any further, and a reset may recognise them again.

If not I would imagine Vida Dice would be the way forward.
There is a test in Vida for injectors
Iain

[rich_f]

Hi Iain,

Thanks for the reply. I actually had the battery disconnected and the leads shorted for a few days (good thing this happened during lockdown...) but I suppose the corrosion on the leads may have prevented a good contact. I'll try it again.

Regarding Dice, is that something only volvo main dealers would carry? Alternatively, if there are any local members with a unit I'd be very grateful of any assistance.

[IainG]

Hi
The "real" Dice units tend to be dealer only. The rest tend to be clones of varying functions and reliability. There are a few on the forum that sell "Set up, Working and Tested" units. Look in the "for sale" sections.
Some members also sell when they no longer have a Volvo.
EBay etc also sell units. Some people have bought these and have had no problems, others have had many issues.

Others on the forum have Dice units that are local and are willing to help. Just request in the thread and you might be lucky.
You can buy a spray contact cleaner (I bought mine from RS) for the plugs and sockets that would clean and protect the contact pins.

Good luck

Iain

[rich_f]

I had another go at disconnecting the battery and shorting the terminals to see if it cleared anything, and I made sure this time that they were properly shorted by checking continuity (the corrosion I referred to earlier was on the outside of the main battery connectors, which I jammed together to short them, not on the injector terminals - though I did clean them with electrical contact cleaner previously as part of the search for the problem).

Upon inserting the key the cd changer went a bit crazy which didn't happen before, but the engine problem wasn't any better.

For this to work, am I supposed to disconnect the battery with the key in and turned or something?

[Cooke]

sounds like your having the same problem as me apart from i didnt mess with the injectors, i tried blanking off the egr like you, i cleaned the throttle body and tried all sorts of other little things but didnt have any luck.

something you could try is unplugging the fuse box/ecm under the glove box because this apparently fixed a lot of peoples problems.

as for the air in the fuel line i have this same issue, i unplugged the lines and bypassed the filter and the air stopped until i connected them back to the fuel filter so hopefully its just the seals to my fuel filter.

my car is currently at the garage so if i found out what the problem was with mine i will let you know. (they think it could be the egr valve so it might be worth while you taking yours off and cleaning it if you fancy the faffing around it takes to get that thing off )

[rich_f]

OK it is running again.

I was convinced that the 2 cylinders not working was related to me disconnecting their leads, and so since disconnecting the battery didn't reset it, I knew I needed a proper diagnostic tool to interrogate the fault codes - so I went on ebay and bought a used DiCE unit. I already have vida installed on my laptop and getting the dice working so relatively straightforward.

Anyway the fault codes were related to the connections to number 2 and 3 injectors - the ones I had messed with. It looks like it puts it into limp mode when these are active too, hence the rev limiting. So I cleared the codes and - still didn't run properly and worse, it stopped and failed to start again, and the codes returned. Taking Iain's advice I carefully cleaned the injector connector terminals (much more thoroughly than the first time I tried) and tried again - still didn't start but the codes didn't return.

When I changed the fuel filter I installed a priming pump and left it plumbed in. I squeezed that a few times and tried again - and it started!

So the running on 2 cylinders and the limited revs were due to the fact I'd disconnected some injectors figuring out why it didn't start. It didn't start because I probably didn't bleed it quite enough after changing the fuel filter - but there's still the mystery of why it didn't start in the first place, or rather why there was that large air pocket in the fuel line. There's no air entering the fuel line as it runs, but maybe it will be there in a few days if I don't run it. I'll have to keep an eye out on that one.

Thanks for your help and suggestions.