Injectors

[Alpine]

Seems that one of my injectors has failed, so I need to replace it.

I need to google and see what I can find, but is the original Volvo part a particular brand (Bosch?) and am I ok to replace one rather than all 5 together? Is a failed injector a common problem on our cars?

[SteveSarre]

Hi Alpine,

Is this on the same car that had the codes and vvt etc? It seems odd that now a failed injector has cropped up.

Steve

[Alpine]

Originally Posted by SteveSarre

Hi Alpine,

Is this on the same car that had the codes and vvt etc? It seems odd that now a failed injector has cropped up.

Steve

Hi Steve, it is, I know its a bit odd. But I'm being lead by my mechanic...

Its still running rough, misfiring I think

When he takes each lead off the injectors there is a dip in the engine note (obviously, because it is losing a cylinder) but if you remove the lead from injector no.1 it makes no difference. So he's thinking its an injector problem. Does that sound right?

[Luxobarge]

No, that doesn't sound right, injectors VERY rarely fail in these cars. The best way to be sure would be to swap that injector for another cylinder and see if the fault moves - it's possible, but unlikely.

Does your car have a conventional distributor and leads, or does it have the individual pencil coils one for each cylinder? If the latter, then more than likely the coil has gone down, this IS quite common. If it's the former, then I'd be looking at the spark plug, leads etc. - again, you can swap them for another cylinder to see if the fault moves.

If I'm right, then I'd junk that mechanic and never go near him again, this is basic stuff.

To back up my claim that injectors rarely fail, try searching on this forum for a misfire fault caused by one - In my 10 years plus of reading every thread in this forum I don't recall any member having had a failed injector causing a misfire, whereas there are plenty of examples where pencil coils have failed, it's a common fault on many cars. Sometimes caused by the wiring to them failing too.

[Alpine]

Originally Posted by Luxobarge

No, that doesn't sound right, injectors VERY rarely fail in these cars. The best way to be sure would be to swap that injector for another cylinder and see if the fault moves - it's possible, but unlikely.

Does your car have a conventional distributor and leads, or does it have the individual pencil coils one for each cylinder? If the latter, then more than likely the coil has gone down, this IS quite common. If it's the former, then I'd be looking at the spark plug, leads etc. - again, you can swap them for another cylinder to see if the fault moves.

If I'm right, then I'd junk that mechanic and never go near him again, this is basic stuff.

To back up my claim that injectors rarely fail, try searching on this forum for a misfire fault caused by one - In my 10 years plus of reading every thread in this forum I don't recall any member having had a failed injector causing a misfire, whereas there are plenty of examples where pencil coils have failed, it's a common fault on many cars. Sometimes caused by the wiring to them failing too.

thanks Luxobarge, it does have the pencil coils as I have had them out myself to check the condition of the spark plugs. So I could swap them round myself to check. But how will I know which coil is bad? Is it by taking the lead off the injector and see how the engine reacts?

[Luxobarge]

Originally Posted by Alpine

But how will I know which coil is bad? Is it by taking the lead off the injector and see how the engine reacts?

Fair question, personally I'd do it by disconnecting or removing (pulling up) each pencil coil one at a time, I'd leave the injectors alone ideally.

With this system the ECU codes can be read which will usually indicate which cylinder it is, but as I guess you don't have a reader that will do this then the old fashioned manual way will work just as well.

[SteveSarre]

Hi both

Happy Christmas!

Surely the symptoms suggest that pencil coil no 1 is the bad pencil coil (if injector 1 is good)? To test that you could unbolt no1 coil and another coil and swap them round and see if the problem moves. I think the coils only work if they are bolted down (for grounding) so you cannot just "lift" them (but might be wrong).

Alpine, also look at the top of each pencil coil. You should see a date stamp (i think year week eg 1999 14). If some of them are more recent that indicates that they have been replaced. Used coils are not expensive. If you have 2 new and three old I would be tempted to replace the 3 old ones (but start with just one).

I have some good used. Will have a look at what I have got. Send me a PM if you are interested.

Also maybe check out getting a new one. Part number is 30713416 and they are used on various Volvo models. I dont have a recommended aftermarket brand

Hope that helps,
Steve

[SteveSarre]

This one looks like good value at £9.60 including postage

https://www.ebay.co.uk/itm/265083562...UAAOSwIe1gSMYQ

I think it is from 2006 week 25

4 are available.

[Luxobarge]

Great stuff Steve!

I was thinking of just "lifting" them to remove the spark from that cylinder. If the misfire gets worse, then that cylinder was working, so put it back. If it makes no difference, then that cylinder was already misfiring, so that's probably the culprit.

Cheers

[Alpine]

thanks both, I got a code reader this morning from Santa so that will help! I will try as you both say, and thanks for the offer Steve I will pm you if needed