Chris
OK folks, I mentioned in passing that when I got my V50 D5 last year it had a misfire at 1,500 RPM. Well time has passed and some interventions have happened to no end.
Car is at 72,000 km, standard D5 geartronic, dealer serviced until I got it then Berry. PO didn't drive it much in the last year or so, and I suspect traded it (on a new Volvo) because it started this behaviour. He had it checked by Silverstone, who apparently found nothing.
Symptoms are an intermittently rough cold idle (i.e. rough>smooth>rough>smooth) that disappears when I drive off. Occasionally dodgy idle when warm - not consistent. Noticeable misfire at 1,500 RPM on light throttle only, at 60 and 80 km/h. Worse at 80 than 60, not noticeable at other road speeds/1,500 RPM however I suspect this is because load is different. It isn't a transitional thing either; if you drive consistently at the right speed it will do it indefinitely.
Unlikely to be transmission as it can be reproduced when stationary in Park.
No codes, of course...
Interventions to date are 2 lots of injector cleaner, new fuel filter, and Berry replaced injector 4 with a second hand one because they were a little suss about it. Berry are reluctant to do more at this stage because they don't want to waste their time and my money on a wild goose chase. Unfortunately that leaves me with a car that is prone to misfiring at the most common speeds, which is not pleasant or likely to be good for the car.
I have also been on a few country drives (4 hours plus), no difference and in fact maybe slightly worse immediately after.
I have seen many theories - EGR, vacuum leak, injector electrical connectors, MAF sensor, fuel rail, boost pressure sensor, vac solenoids, perished distributor and camshaft end seal, dirty glow plug relay but nothing definitive, and the only D5 I have come across on the net with my exact symptoms never had a resolution.
So, if anyone has come across this and has a solution or even an order in which to start troubleshooting based on known issues that would be most appreciated.
Vee_Que
I would never fit second hand injectors. Going to a diesel specialist is my recommendation as they face Bosch training. From memory, rankin diesel is just that. And they are Volvo guys with a 140 and 240 Hill climb car.
timbo
I would start with the electrical connector. You can close up the contacts with a small flathead or a pick tool.
Check the swirl arm and intake flaps as i have had them cause misfire issues.
Most of these issues will leave fault codes in my experience though.
Egr/throttle body could do with a clean if it hasnt been done but its a bit of work to dismantle it all.
You need specialist tools to go any further in terms of testing the fuel system.
Fuel issues wont necessarily code either
VolvoDeger
try to disconnect egr plug and see if still misfires then go from there
Dauntless
Clogged EGR/intake shouldn't cause it, but should be cleaned anyway. It was a pretty easy job on the XC90, if that's useful.
VolvoDeger
not looking at clogged but opened more percentage that should be especially those first few minutes at idle
Chris
All great suggestions guys, thank you
Chris
@Philia_Bear now you're back in town, any thoughts?
Philia_Bear
Post a video
Easiest thing to do is get up to speed and force the trans into manual 6th and then roll into it from 1300rpm through 1800rpm
Chris
Unfortunately it won't show up on a video - it isn't a dramatic thing, just noticeable - feels like hitting a slightly rough section of road
Philia_Bear
The d5 is unbalanced it is not all that smooth
My xc90 does exactly what your describing, its just part of the tune
Vee_Que
Actually, 5 cylinders are meant to be better balanced then a 4cyl. But harmonics can cause it.
Chris
Interesting, the PO felt it had changed enough to report it and he had it from new. I suspect a little more digging is still worth it.
Also worth noting this is not a regular misfire, it varies in intensity so that on some cycles it is almost non existent and on others the car jerks noticeably
Chris
OK update time. I decided to go to Voldat as I have a long term history with them with other cars. I told John to take his time and work on a definitive diagnosis. Well today I got one.
It's never good when a conversation starts with 'your car has major problems'. Apparently I'm looking at damage caused by water contamination of the fuel.
So it looks like a set of new injectors, new fuel pump and serious clean out of the fuel system at least.
Quote yet to come, but yeah it will be big. Oh joy.
Philia_Bear
Chris;c-139404 wroteOK update time. I decided to go to Voldat as I have a long term history with them with other cars. I told John to take his time and work on a definitive diagnosis. Well today I got one.
It's never good when a conversation starts with 'your car has major problems'. Apparently I'm looking at damage caused by water contamination of the fuel.
So it looks like a set of new injectors, new fuel pump and serious clean out of the fuel system at least.
Quote yet to come, but yeah it will be big. Oh joy.
Lots of water or?
He send the fuel off to be tested?
Chris
He's working with the diesel mech nearby, who suggested the injectors were squirting a very milky mix. They are out of spec and showing the effects of the damage, not surprisingly.
Haven't had the fuel analyzed, but this issue was there when I got the car so it's 2 years worth of contamination at least. My guess is the PO frequented a cheap, shitty local servo with low turnover and poor tank hygiene. I don't, but it's too late now.
Philia_Bear
Chris;c-139408 wroteHe's working with the diesel mech nearby, who suggested the injectors were squirting a very milky mix. They are out of spec and showing the effects of the damage, not surprisingly.
Haven't had the fuel analyzed, but this issue was there when I got the car so it's 2 years worth of contamination at least. My guess is the PO frequented a cheap, shitty local servo with low turnover and poor tank hygiene. I don't, but it's too late now.
its $120 and well worth it
Chris
Fair call, I'll talk to John about it today
Chris
And the cost will be, drum roll... $6,000 for a set of injectors, fuel pump and clean out of the fuel system. Kind of what I was expecting really, if not what I was hoping for.
carnut222
Chris;c-139537 wroteAnd the cost will be, drum roll... $6,000 for a set of injectors, fuel pump and clean out of the fuel system. Kind of what I was expecting really, if not what I was hoping for.
Wow that's a lot of money! I think I could live with the misfire or time to trade it in. Bummer. Remind me not to buy a diseasel
