Normally aspirated diesel smoke / power question

Smoke means one of two things - oil being burnt or excess fuel. Oil smoke is blue whereas overfueling is black.
Has it recently passed an MOT ie emissions checked ?
You could try some injector cleaner in the fuel but suspect that reconditioned injectors are probably needed if over 70,000 miles and they haven't been changed / reconditioned before.
The Peugeot items are a common injector so often are avaiable on an exchange basis. Forget accessory shops - look for a diesel specialist. They unscrew the "working end" that is in the combustion chamber and change it along with the centre "needle". There is also a spring inside that can stick causing the injector to "dribble". Don't bother trying to DIY recondition as parts can be difficult to find and they can be a PIA to dissassemble plus there is a risk of damaging the injector, .
Think of injectors like spark plugs - they don't last forever and need changing every so often.

paul H

I can't guarantee it's injectors but black smoke is definatley an overfueling problem so choice is either pump (expensive) injectors or timing (doubtful).
Removal of injectors is as easy as a spark plug. You need a suitable deep socket so probably best buying one made for the purpose. Every time you remove an injector you need to change the copper sealing washer. These cost pence from a specialist. This often is stuck in the head and needs to be hooked out with screwdriver or similar. Looking at the working end of the injector you should see only the smallest bit of the needle - maybe 0.5mm. Over time the body errodes so more of the needle is visible. If you remove the injectors a specialist will be able to put them on a test rig to check spray pattern and a decent one will tell you if they need changing, cleaning or are OK. Under no circumstances try this at home - the pressures involved can spray diesel into the skin as easily as a hypodermic needle.
Secondhand injectors can often be useable so worth checking out eBay and scrapyards. At worse they can be used as core units for reconditioning so your car doesn't need to come off the road.
No idea of current costs but last time I had Peugeot injectors reconditioned (for 205) I paid under £15 each.


Paul h

If yours is a lucas pump, when tuned they tend to make a LOT of smoke if done even slightly too much, without the corresponding amount of power you'd normally expect!

It's a Lucas pump - So I'm guessing that to attempt to fix the unequal power delivery issue and the smoke I should first try recon injectors first and then if that doesn't help look at fuel pump settings? How would I tune the pump, would it be covered in the Haynes manual?

I doubt Haynes will show you, but there's loads of decent videos on YouTube for tuning 306 diesels and pump fiddling.

Personally i'de go to a diesel injection place and get the existing ones checked and reset to the right pressure last time i has some done it was £12 each cash

Right, today I was on the way from London to near Horsham and Haywards Heath to pick up some roof bars for it. I went past a place called First Diesel Injection near Croydon. Bearing in mind the comments here I thought I'd stop and ask for a professional diagnosis.

The owner (Peter Bourne) was great. Stopped what he was doing and came out for a look - after some hard revving and filling up his yard with smoke he pronounced the EGR valve faulty and blocked off its vacuum pipe with a ball bearing.

He said don't put any fuel cleaner in, don't try pulling the injectors (he said even though he was sure they'd be past their best at that mileage, they look rusted in and could strip their threads) and don't use low sulphur supermarket fuel. Then he sent me on my way by telling me to give it a good motorway blast. Result after 50 miles at 80 - 90 mph? Problem solved, it feels like a sports car in comparison and no smoke at all!