looking for ideas to.check .
volvo fh 480 2006 the turbo gauge only boosts half way into the yellow on the dash . truck used to be exelent puller but now its guttless for instance leicster bank 35-38mph at 44t . volvo 440 are passing me with same load and this thing used to make the 520 looksilly on hills as has no add blue system .
fuel consumption running light about 35t 99% motorway driving at 50mph is avreaging 6.8mpg with a flat trailer on
any suggestions
thanks
You would be better off putting this in the owner drivers forum mate, the only reply you would probably get here is ‘get a Scania’! 
Long shot but might be the fuel system getting blocked up, my Volvo has twin tank and had been messing about only pulling fuel from one tank, and I was never impressed with the power or fuel economy, its a 520 pulling 30 tonnes, but didn’t feel it.
They cleaned the fuel towers and it seemed like a different truck, loads of power and an improvement in mpg. They reckon the system was so blocked up on both tank it was a surprise it ran at all.
Most fitters will say it’s the ecu or something on those lines. Volvo and scania have similar electronics. There are 4 resistors and 4 diodes that go wrong. £44 + vat to fix it. The usual yell tail sign is lack of power, and various random faults like trailer abs for no reason.
Split or leaking intercooler trunking or blocked,dirty or holed intercooler matrix.
Start with the simple stuff, air and fuel filters clean, exhaust brake not sticking, no boost leaks etc. might be worth dropping the silencer off and giving it a run in case the silencer is slightly blocked.
I’ve not had much to do with volvo’s but if there’s a standard waste gate on the turbo make sure it’s free and not starting to seize etc.
2 possibilities of simple fix.
1, inter cooler pipe leaking, is there a whistle when accelerating?
2, blocked pick up pipe in the tank. There is a little plate riveted to the bottom of the pickup, with the rivets drilled off, there is a gauze inside that gets blocked. This will normally bring up a fault in the engine Ecu diagnostics as mechanical fuel feed pressure.
Have a scroll through the dash diagnostics for the engine Ecu and list the faults here or pm if you want
Clean turbo/new turbo. Blocked fuel lines/filter.
Probly turbo though if boost gauge doesn’t fill to top under load.
My 460 went like that, turbo boost gauge would only go just into the yellow and shockin mpg. 20 mph up windy hill west bound! Was the exhaust box, now turbo gauge goes off the end of the scale and goes up windy hill now at 45 mph. Fuel economy back to normal. Only problem is that it cost £6000 
I’m seeing more and more blocked silencers lately its one of the first things I check after the really obvious stuff.
limeyphil:
Most fitters will say it’s the ecu or something on those lines. Volvo and scania have similar electronics. There are 4 resistors and 4 diodes that go wrong. £44 + vat to fix it. The usual yell tail sign is lack of power, and various random faults like trailer abs for no reason.
i will suggest that to them as i sometimes get abs fajlt then turn.ignition of start back up and its gone again and dont see if for few days then will do same again .
thanks for suggestions i will look into things . for instance friday morning fired her up and ran.back.into yard and it pulled like.a train boost to.end of turbo gauge and only dropped 2mph running up.leicster bank at 44t as apposed to day before losing 15mph
did you get to the bottom of this?
having similar issues with a 57 plate with add blue
I’ve got a 64 plate FH 500, we’ve put a new DPF and turbo on it but still it struggles up hills, I’m dropping to 30mph on the a19 going towards Eden castle if anyone knows where that is. Where can I go from here to solve that issue?
Any help is welcomed, thanks.
Nee98:
Where can I go from here to solve that issue?
Any help is welcomed, thanks.
Norfolk . . . Holland . 
Nee98:
I’ve got a 64 plate FH 500, we’ve put a new DPF and turbo on it but still it struggles up hills, I’m dropping to 30mph on the a19 going towards Eden castle if anyone knows where that is. Where can I go from here to solve that issue?
Any help is welcomed, thanks.
On our it was the exhaust, drops to bits on the inside and becomes massively restrictive. What proved it was when an exhaust clamp snapped after the turbo and she had full power! So try taking one off and see if it makes a difference
Jesus.
Thread resurection time.
Ken.
Deleted…didn’t realise it was ressurect 8 year old thread time.