Technical Marea Weekend SX 110 JTD black smoke

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Technical Marea Weekend SX 110 JTD black smoke


Is it me?
Oct 8, 2007
Near Bridgwater, Somerset
Just thought a tale of my recent saga might be of interest and am posting this primarily to thank the Forum for helping me resolve it myself and to help anyone who may have the same problem in future.

My September 2001 51 plate Weekend has done 75000m. I've had small Fiats in the past, 127, Pandas, Seat Marbella (old Panda lookalike) and a Uno, but this is our first Fiat 'main car'. I just love Fiat engines (and style). Apart from various electrical niggles, mostly down to eccentric Magnetti Marelli electrics/bad earths (why didn't they stick to making the ice cream), I love her dearly (but abuse her terribly as she's primarily a dog transporter, and it shows). She's also our first diesel and I certainly won't go back to petrol now. Mostly main dealer serviced (Huttons at Weston-super-Mare, where I'd bought her as an ex-demo with 5000m on the clock) but every now and again I save expense and use a good local garage. The local garage did the last service at 72000 (though I'd got the dealer to change the cam belt at the previous 60000/5 year service).

Over August Bank Holiday, about a month after the last local service, the car started blowing a lot of black smoke and running a bit lumpy. Being completely non-technical, I first suspected crappy supermarket fuel, so gave a shot of diesel Redex on subsequent fill-ups with 'proper' diesel. No difference. Then, being suspicious of all garages I suspected they hadn't changed the air filter, but on checking found that I had brand new air, fuel and oil filters, albeit "Fram" rather than Fiat ones. (Unlike the Fiat all-paper air filter, the Fram air filter also has a foam layer). Local garage suggested a pint of Wynn's fuel cleaner, which they say is what gets most diesels through their MoT, but that didn't do the trick so took it to Huttons for a diagnosis. They diagnosed overboost fault and replaced the overboost valve at a cost to me (including £40 diag) of £232. No difference. In fact, after this the injection failure warning light (aka engine management light) started flicking on and off intermittently when accelerating at speed. Took it back and they changed the fuel filter for a Fiat one as they'd noticed a non-standard filter, charging for the part only. I also bought and fitted myself a Fiat air filter, just in case. Still no difference. Back to Huttons. Re-diagnosis still showed an overboost problem so they booked it in for 2 days next week to have yet another look. Offered a free courtesy car (they usually charge £9/day).

Meanwhile I dug out all this stuff on the Forum (below). Thought it might be useful to others to have it all together. And the last thing I found was about an air leak causing overfuelling (13 below). Well that's something even I can do, so I checked all the hoses and their connections thoroughly and blow me down found a large split in the underside of the big hose that feeds into the top of the engine (I think between the turbo and the intercooler?). Bodged it up with duct tape, took it for a blast to burn out the waste soot from the system and it's now fine - no more smoke and no more lumpy acceleration - so delighted in telling Huttons that I'd found the fault myself and ordered a new hose for them to fit next week. I trust they won't try to charge me.

Any views on Huttons and/or whether I should pursue the £250 it's cost me so far, when a simple replacement hose was all I needed? At least I've now got a spare air filter as, clearly, the Fram one is fine for next time.


10. How about cleaning theMAF sensor as described for the Bravo at (see link 6 above)
just done my Punto JTD (same sensor) as having intermittent lack of power. Seems to have cured it. Use something like Maplin Electrical Switch Cleaner to clean the wires and contacts.

11. E.G.R. valve (exhaust gas recirculation) if fitted to vehicle may be stuck open. Also may be a fuel pump timing/pump internal fault (see link 1 above for cleaning the EGR valve)

12. Timing sensor problem?

13. Black smoke is a sign of over fuelling, it can be caused by an air leak between the turbo/intercooler/manifold. Have a good look around this area for a damaged pipe loose fixing."
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Well, I sent the missus (redhead) to get the new hose fitted and Huttons at Weston-super-Mare apologised for not spotting it themselves (and replacing overboost valve and fuel filter unnecessarily), and gave her a £158 refund. So it's all turned out well in the end and I think that's a fair result.
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good thing you got a refund because thats the first thing they should have checked.. sooty or black smoking means overfuelling, because there is not enough air to burn the fuel, usually because of a lack of boost caused by split pipes or turbo problems..