The 1.8 petrol will be more reliable than the diesel as there's technically less to go wrong. However they have suffered from excessive oil usage. Wasn't there an issue with the heads too?
However, the 2.2 diesel is a reliable unit, what screws them up is stupid remaps that causes the turbo to fail.
The cracked manifold issue is a pain though. 191k miles on mine now and still chugging away(I'm amazed).
Like all cars, full service history or not, you buy on condition. You're looking at replacing suspension, linkages and brakes on these cars now due to the age of them.
Sometimes it's more financially viable to buy something a lot newer and just bang the miles on it, like I have my 2.2 keeping it long term then scrap it when it finally does fail. Then repeat.
IMHO it's just uneconomical to go out and buy another CDTI. They fall under the ULEZ rules and will be ÂŁ12.50 a day to go around London, and when they come into other city centres I'll be paying ÂŁ7.50 to drive through town centres.
Whereas I buy a petrol model, I can drive for free despite the vehicle being the same age & price. And the manifold job on the CDTI is so costly. It's just not worth it on such an old vehicle.
My diesel had constant issues with the boost pipe clips coming loose etc as well, so when you do begin messing with things it causes permanent problems.
I know the suspension and brakes will require doing on pretty much all vehicles, as they're service items. But it still adds up on the cost, even with trade discount in all the part merchants & Honda dealer. To throw the manifold on top, I'll be ÂŁ2,500 deep into another CDTI. The best option would have been to buy my tried and tested CDTI back from the insurers and then source another CDTI with a blown engine, but then I'd just run up the thousands of pounds on suspension work from higher mileage. And of course, more time off of the road.
As for the problems with the R18, with them all being so old and with 80k+ miles, I'm fairly confident if the engine was to crack it'd have done so by now. I'd expect a 12+ year old vehicle to burn/lose some amount of oil. I ain't 100% set on a Civic currently, I might buy a Toyota. Whatever I buy will be Japanese (Toyota or Honda only) and petrol however. I ain't really into travelling long distances for vehicles. If the price is fair and it's within 50 miles of my home address, I'll travel to view. I've walked away from about 5 or 6 vehicles for every one I've bought, easily.
Also the diesel will do double the mileage of the petrol. I'd say the CDTI is good for 250K with ease if well maintained. The petrol around 170-200K miles tops.