Technical Car problems

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Technical Car problems


New member
Mar 4, 2022
Saint ives Cambridgeshire
I have a fiat cinquecento 899cc I not had the car long within 2nd day of owning it it broke down as drive belt snapped from day 1 car smell like burning oil and was leaking oil and slight water leak and smoking from manifold and white smoke from exhaust and small amount oil in water I put a new drive belt on and then 1 week later car broke down again this time fuel pump had gone so replaced fuel pump and then running ok for about a week then starting making ticking noise I though ok head gasket so replaced headgasket 1st start car sounded fine but still smoke coming from manifold and oil smell and rough on idal drive it around a bit smoking has gone oil leak gone oil in water gone car drives but slightly lumpy on idal when I drive it sometimes it lacks a bit and then picks up again any ideas of y it's now doing that also I have a spark plug that needs replacing as is bent a little at top could this be the issue or is timming or possible head bolts can anyone help
I'd certainly start with the spark plug to rule it out. If it was damaged in situ or if you don't know how it was damaged, I'd look to replace the leads too - they may have taken a knock.

It sounds like you had a bad head gasket and an oil leak on to your exhaust manifold - sounds like you sorted it.

I only know the 1.1 so these may be a bit off.

I don't think it would be the head bolts, sounds like you have dealt with the leaks. Timing is very hard to mess up on these if you have put the belt on right. The rest is taken care of by the ECU. I would certainly re-confirm your timing marks, though, if it's off by one tooth it will run but badly, like you're describing.

Rough idle and lumpy power could be a few things, if it's not the timing belt, start with the plug and leads to rule them out. There's a chance that the lambda sensor is contaminated depending on what got out through the exhaust and for how long, there are some good guides to test this with a multimeter.

Coolant temp sensor is a possible - apparently these are relatively bad/known to fail. Again, there's some good guides on here or if you have more money than time they are pretty cheap (this is the one on the intake manifold, gearbox side).

Let us know how you get on and sorry if my 1.1 stuff doesn't cross over to the 0.9 perfectly.
The only belt on the 899 is the auxiliary belt that drives the alternator and the coolant pump.

Camshaft is chain driven and low in the block. Valves are operated by pushrods & rockers.
Removing the head doesn't effect the valve timing.

Common for the rocker cover to leak oil, usually due to the bolts being overtightened, distorting the gasket.