I need repairs to my Citroen C4 Picasso diesel. I need someone who has a diagbox and can use it here, so as to be able to find the exact problem. The problem appears to be related to general engine management , but maybe specifically to the injectors. I hope to find someone able to diagnose and then fix the problem. My days of working on cars ended when they got electronics.
Any garagiste (not just Citroen) should be able to at least diagnose the problem, and likely fix it.
Edit - sorry, just realised you need a mobile fix, maybe get your insurance to take the car to a garage?
The car drives (in limp mode) and is road-legal. I need to be able to speak in depth about the problem and garages won’t do that any more.
OBD adapters are pretty cheap if you just want to find out what the ECU thinks is the problem search for “obd2 diagnostic” on Amazon or your favourite purveyor of online tat.
Yeah, but you need to understand the OBD readout. I’ve a wifi one that’s fun to use but what will I do if it says injector three is misbehaving? Go to the dealer
Why do you need to "speak in depth:? Roger. All the OBD does is point to things that are not working, The “in depth bit” IMO opinion is whether to fix or replace. Years ago I had a tatty but much loved Golf GTI which cut out intermittently. I eventually took it to a VW dealer who ran the diags and told me that a pin in the fuse board was wonkey. We had a look and he said we need a new fuse board, I said “bend the pin”. The problem never reoccured
I have a pretty serious engine fault. Or so it says on the display (Moteur defaut - garage) + SERVICE. This was on the screen for months but the car drove fine. Then lockdown, car unused for 2 months or so. Found battery was flat and a 3-day charge didn’t help much - was flat again after few days. Battery removed, new battery put in a week later. ‘Defaut moteur - garage’ on the display gone; SERVICE light gone. Car perfect. For about 4 weeks. Then, suddenly - ‘Moteur defaut’ ‘SERVICE’ again, also limp mode, auto gears not changing (paddles ok). I have an OBD reader and had a look last year, but it didn’t say anything worth knowing. The car has had 2 full diagnostics at garages which both show the same - needs 4 injectors + other stuff (about €1700). I refuse to believe that 4 injectors can go at same time.
The diagnostics showed that all of the car’s stored information had been wiped before I bought the car and I am suspicious that the former owner sold the car with fault, which is against the law. My efforts to get recompense have come to a dead end - I’ll have to spend serious money in order to see this through and I can’t do this.
In that case you have a problem - a garagiste is going to start with what the OBD is saying and fix that - and is likely to want to change the injectors as the first move.
I’m not sure what else is possible, unless this fits a pattern which is common in the Picasso.
That’s a bummer Roger. What make and type is it?
… Original posting.
I did a quick Google on Picasso injectors
I would have thought with the aid of a Haynes manual one could have a go at replacing them oneself? Just like spark plugs but with a few wires and pipes.
Just saw this is a petrol injector duh! But maybe diesel ones are also available at a good price.
Not quite - on some engines the ECU needs to be tweaked when they are changed to “marry” the new injector and engine, and the pipes can be at eye-watering pressures on high pressure common rail engines (20,000 psi)
I’ve had over 80 cars; worked on many of them. Rebuilt gearboxes, back axles (when some cars had them) - even rebuilt an Ro80 rotary engine. And all sorts of minor things. But now I’m beaten with electronics and the special equipment that is needed. Sadly, it ain’t any longer just a matter of changing injectors as if they were spark plugs. Hugely complicated just to get the old ones out. I have thought for years that manufacturers have made cars unnecessarily complicated and difficult to work on unless you are a main dealer, with all the special tools.
I would have liked to have participated the RO80 rebuild. I was offered a GS rotary with a spare engine a couple of years ago. The guy selling is was a friend, Andrew Brodie, the foremost SM expert in the UK. I should have bought it
Only eye watering if you don’t tighten them correctly I was talking to a truck garagist last Sunday and he told me that even they can’t diagnose problems, the truck has to be connected to Man or whoever’s HQ. That’s got to be an anticompetitive lock in.
If you view it from the point of “does the engine need all that paraphernalia to work” then it might seem unnecessary - but I don’t think that manufacturers have done it just to styme small independent mechanics.
Modern engines have to meet tight emissions and efficiency requirements, and people want cars which start without fuss in the mornings - which fuel injection and engine management largely deliver (do you really want to go back to the sort of reliability that we lived with in the 70’s?)
But, you are right - there is a YouTube sub-genre that I occasionally watch which involves people filming themselves getting motors running which have lain in fields for 40 years - typically big American muscle jobs with massive displacements but almost always carburettors and distributors. I frequently wonder what a modern engine would take after 40 years where you have not only seized valves and pistons to worry about but rotted (and probably unobtainable) electronics to cope with as well.
But illegal in the EU where manufacturers have to allow independent’s to work on the engines.
The guy I go to seems to cope perfectly well - but it certainly drives his costs up.
No definitely, but it’s a fortunate side effect. There’s no reason my Man man couldn’t carry out the diagnostics himself, but he’s no access to the S/W to do so. I know my Volks and Merc are plugged into Wolfsburg and Stuttgart at service time. I don’t think that’s necessary either. In fact, I wonder if uploading my ECU data is a GDPR breach
Engiines, IMO, have never been simpler. My diesel Tiguan produces 240 BHP, the Merc 300BHP. Both four cylinder two litre engines, one diesel, one petrol (albeit with a bit of help from an electric motor).
In the seventies a Ferrari Dino 246 produced less that 200BHP. In order to so that it had six cylinders, three double choke Webbers correctly jetted and choked (optimised for a specific rev range), optimised inlet and exhaust ports, valve timing and cam profiles, combustion chamber and tuned exhaust pipe lengths. Etc. etc.
Turbochargers changed all that, as good an a supercharger without the power sapping disadvantages. They stuffed the cylinders regardless of sloppy porting, valve overlap etc. Just they were a bit uncontrollable.
Bosch Jetronic made injection affordable (and much more reliable and accurate than the old mechanical sort). So now we had the right mixture across the whole rev range and for all loadings.
Emissions also became an issue…
Enter the ECU and sensors. Now all the fixed aspects, the tricky stuff, of the Dino (or any other) engine became variable. Check if there’s too much naughty stuff in the exhaust, reduce fuel:air mixture. knocking (preignition) detected in the engine, increase fuel:air mixture and or retard ingnition etc etc etc. And check that a hundred times a second.
ECUs allow dogs of engines to run sweet as a bird but they are not complicated. Any clown could program one… if X > Y do Z, else do ? All based on a map for that specific engine. That’s why remapping can unleash undreamed of power in a relatively modest lump
I’d bet my barnie there are many, many more lines of code in a car’s infotainment system than in the ECU(s).
I don’t see any reason for a manufacturier to restrict access to ECU diagnostics but that seem to be what has happened to my Man man. BTW, he said the trucks have five “computers” on board