Seeing as things are a bit quiet on the forum, I have the aircon fixed (turned out the engine mount had rubbed a hole in the high pressure line) and I have now racked up a few miles, I thought I might give a bit of a review of the Mk1 C3 1.4 petrol auto, about 17 years too late. LOL!
Still being fixed up
Interior is pretty good
The 1.6L petrol engine in the C2 I own makes it spritely and lively, I cant say the same for the 1.4l in the C3. Yes, it is a 1.4L, so what did I expect? Around town you really need to work the accelerator peddle to keep up. I have found running the auto in "manual" mode squeezes a bit more oomph out of the engine so I think the manual gearbox version would probably give better performance over all. Having said that it's highway performance is a bit better and doesn't seem as boggy on the acceleration as I expected. Highway economy seems to be about 8 litres per 100Km or about 29 MPG. That's just looking at the average of the instantaneous reading on the dash and not numbers from the petrol pump, so take that with a grain of salt! The little engine is easy to work on but it needs to be because you need to pull it apart to get to anything! Over all much easier to work on than the 1.6L. A lot more room in the engine bay than the 1.6L. Considering it will only be me in the car mostly and the better maintainability, for me I like the 1.4L. If you plan to put more than the driver in this car (including fluff, lint and dust) I'd recommend the 1.6L!
On the road the ride is smooth, quite and comfortable. The C2 is NOT an open road car. The best thing I can say about it's ride is...harsh. In contrast the C3 is very comfortable on the highway and indeed around town without being "loose". There seems to be less road noise in the C3 than the C2 but that might be down to the tyres? The C2 runs a very low profile tyre. The C3's little bubble shape gives the driver a high driving position and excellent visibility but I feel the wing mirrors are too small by comparison to the rest of the visibility. The C3 is deceptively small. It's smaller than my 1984 Ford Meteor (Mazda 323) which I consistently "loose" in car parks behind regular sized cars! The only thing is the C3 is taller and the roof is a bit easier to spot.
The "lock-up" type torque converter is a bit hit and miss. Highway RPM is under 3KRPM, surprising low for a little motor like this but as I said, acceleration doesn't seem to suffer at speed. Unfortunately the downshift to stop at lights gives you a lot of engine brake and you need to back off on the brakes for a smooth stop, or you go through the windscreen. This might be the dreaded modulator valves in the gearbox sticking but it seems to be the way the gearbox is designed. The kick down on hills ETC is a bit alarming as the shift down from 3rd to 2nd causes the rev-counter to go off the chart. Again, running it in manual mode means you can shift down before you loose momentum and keep the torque up. EDIT: it turned out that pressure modulator valve WAS causing the erratic gearbox behavior! Ran much better when the valves were replaced.
Years of being in the sun means the clear coat on the paintwork is in poor condition. This problem is by no means confined to Citroen or the C3. The funny thing is my C3's twin (lying in state) has very good paint?! Considering the body shell is nearly 17 years old it's in excellent condition. Manufactured to survive Europe's rain and salt means the low rain fall and lack of salting of the roads here means the shell is virtually rust free. I say virtually because there are small patches of surface rust at the top between the roof and the tailgate where paint was not applied correctly but over all construction is very good. The check straps on both C3's driver's doors were damaged. I don't know if this because of wind or the owners but it seems to be a common problem. So don't allow your doors to swing open and bang against the stops.
I mentioned the front shock mounts in the post above. Oh Boy

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The exhaust resonator had a hole in the lower part with very small, yellow crusty deposits on the edges and seemed to have been eaten from the inside out. I believe this was from cheap petrol with a high alcohol or sulphur content. If left in your tank for a long time, the alcohol will absorb moisture. I have no proof of this being the problem but appearing like it's been rusting from the inside, I assume it has something to do with the fuel. The point is, avoid cheaping out on the fuel, it might come back to bite you.
The interior is a bit cheap and "plasticy" BUT that's not all bad! The interiors had stains and greasy marks all over the place as you get with years of (ab)use. I found the ubiquitous spray-n-wipe type kitchen cleaners removed most of the stains with ease, even on the seats! All of the "soft feel" silicone on the dash buttons had disintegrated leaving a gooey, sticky surface on most the buttons. The C2 suffered the same thing as did it's passenger side air bag. So, on the C3, I removed the goo from the surface, leaving the buttons just white

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The biggest problem I have found with European cars by comparison to Japanese cars is the quality of components. Things like shock absorbers, springs, starter motors and ECU's. The European manufacturers seem to contract out to the lowest bidder and change contractors on an hourly basis. This means the components are made down to cost and quality tends to suffer and why you might get a Bosch, Valeo, Seimens or Sagem ECU to do the same job. The Japanese seem to stick with their know contractors and keep an eye on component quality. Just an observation.
Frankly I have spent too much money getting
this car back on the road and could never sell it and recoup the outlay but that doesn't mean I won't sell it. However, I will continue and get the other C3 back on the road too but I will probably keep that one. It's difficult to say if I wasted my money. In the end I will have two neat, clean and reliable little cars. I guess I could consider it a hobby of sorts and write off the money that way?