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Pinking not so bad :-O

My dad had a look at the plugs etc today. They were a bit tight :-D. Unfortunately his feeler gauges are only in Imperial :-(. The gaps were 23/1000, 23/1000, 25/1000 and 26/1000. They should be 0.6mm (about 23/1000-24/1000). There was some carbon on top of the pistons, but he said it's nothing to worry about, it was only a thin layer. I also noticed that some of the carbon on my spark plugs seems to have been burnt off.

We put the old plugs back in (the ones that came with the car) and set the gaps to 35/1000 (about 0.9mm), which is what they should be on the Cinquecento. I didn't actually realise that the gaps were wrong until just now :-(. Anyway, after driving, the pinking is hardly there at all :-). It is a bit harder to start though :-(.

As the gaps have effected the pinking, does this mean that it's not the carbon causing the predetonation? Does it seem right for the gaps to be so different for the Sei and Cinq even though the engines (and many of the other parts) are identical? Another possibility is that the old plugs were cleaned before being used.

Reply to
Peter
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I think I'm getting somewhere now! After driving the car again, a proper drive, I realised that it had just moved the pinking to different rpm's and with normall driving I think it was just really quiet. Today, 2 days later (after 4 trips to uni 6-7 miles), I put the other plugs back in with the correct gaps.

When I took the plugs out they had coke around the ends of the threads. Is it normal for this to happen in just 2 days? 6-7 miles isn't a particularly bad journey either, the traffic was also good on each trip ie. not much stopping.

Anyway, I've got the plugs in at the correct gaps now. I put 10 litres of Optimax in the tank (half Optimax and half BP cleaner Unleaded) and went in search of some NSL's. After a while I found some roads which looked like they were going to change into NSL's, but I realised it was Oxfordshire (stupid limits) :-(. After a while though they did change though, to 50mph. Did 45mph most of the way and then realised how to read the speedo and went up to 50mph lol. The journey was 18 miles in total with pleanty of thrashing. The pinking hasn't gone completely although It's a bit better at the moment. When I got back there was a burning smell though, would that have been the clutch? :-O There was no smoke and I couldn't see any damage in the bonnet, it smelt a bit like burning wires to me, not too bad though. It seemed to be stronger near the back of the car, where the exhaust is.

Reply to
Peter

Both the Sei and Cinq used the same engines (although the 900 has been discontinued now) and for both 900 and 1.1 engines the plug gap is

0.9mm. You had the gap set way too low at 0.6mm and this could quite easily have caused or contributed to your poor running.

Stuart Sharp

Reply to
Stu

I doubt it was the clutch unless you were slipping it lots. Clutches, brakes and hot oil etc. all have pretty distinctive smells, but I wasn't there to smell it :). If the handbrake / back brakes are binding you'd get a brake lining smell at the back of the car.

Reply to
Doki

No, the clutch does seem a bit strange to me. I have heard that the clutches are bad on the Sei, but I would've have thought that they were that bad. I only used 1st, 2nd and 3rd (for more than 40mph) so the actuall number of gear changes would've been less than usuall.

Pinking's back to normal now :-( It's either not due to being coked up or it's getting coked up at an unsual rate. Is it possible for a bad fuel filter to cause the engine to coke up? For some reason, when I fill up with petrol it's usually faster and the engine even sounds better. Somebody suggested that it could be the fuel filter. It seems strange to me, I always look forward to filling up :-D

Reply to
Peter

More depends on how you're changing. Changing up by lifting the throttle and blipping your downchanges, or at the other end of the spectrum keeping your foot to the floor and just dipping the clutch to change up and then slipping it to change down.

Are the plugs right now? I'd suggest more thrashing if they are. ISTR it took a 200 miles or so of hitting the limiter at full throttle in every gear bar 4th all the time before my Mum's coked up Polo ran properly. The thing about the difference filling the car with petrol makes seems bizarre though. I don't know anything about how the fuel pump / tank end of things works, but presumably if there's crap in the tank it'll be at the bottom and could restrict fuel flow when you get towards the end of a tank. I imagine the ECU would compensate for the fuel starvation, not sure if the MIL would come on or not (certainly doesn't in my Ka when there's 2p worth of petrol in and you go round a corner)...

Reply to
Doki

My changes were quite smoothe and I did try to match revs, although I did pull away a bit faster than usuall.

The plugs are set to what the workshop maual says, although I'm not sure that the ws manual's correct :-(. After my thrashing the pinking was almost completely gone, but it's back to normal now. A don't normal get to the end of the tank. There isn't much more that I can try and as I said before, I'm not allowed to do any repairs. That includes taking the car to the garage and paying for them. The only time I can do things is when my mum's out.

Reply to
Peter

I think it was oil :-) I had a small well of oil sitting on top my engine and it's not so liquidy now, it looks like half of it's burnt. It's from a very slow oil leak. I seem to have a leaky rocker box cover and cylinder head gasket. Somebody told me that they've got the same and that it's normal. After a month of being cleaned up, the rockerbox cover is just shiny at the edges. It seems to be the head gasket too though :-(

Reply to
Peter

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