Hi all,
Thought id better put something back into this forum as it helped me alot..i have a 2001 1.8 nissan Almera with 78000 on clock, with all the same problems ie, juddering, rev counter erratic, misfiring when cold and finally engine management light on with fault codes telling me that the cam sensor and or crank sensor was inop.i changed coil packs, spark plugs, sensors, all with no fix...did some reading up and looked in the timing chain, and when i looked through the oil filler cap i could actually lift the chain slightly off the cam spockets. So £120 for the kit, and got the cd rom manual from an auction website, and was a real pain of a job, as you have to take the sump off and remove and engine mount,(but managed not to take the exhaust off like it says in manual!) but i managed to do it, and i have done about 5k in it since then and its not missed a beat...i only did it myself as the cost of a garage or nissan to do it would have been worth more than the car!!..once the chain had been removed we found it 3 links longer than the new one (about 1 inch), hence the misfire!!..im actually surprised the car was still running with the old chain!!
so, it is possible, with a little hard work to do it, and i may have another 10 yrs out of the old nissan yet!!!..now at 82000 its barely run in!!
hope this helps