460 spark plugs and occasional poor starting/lumpy idle

[AndyPants]

Hi everyone, some advice would be very appreciated

My 45,000 mile '96 1.6i 460 (with practically FSH) occasionally fails to start when cold, but more often the idles a little rough (but the idle usually remains around 1000rpm). If trying to drive it when its particually lumpy and only just started it misfires but when its acting up, once it gets warm its fine again for the rest of the day atleast.

My first point of call is of course the spark plugs. However after getting some new plugs and eventually finding a socket extension to actually fit the damn things (as my old plug spanner was too small), with much difficulty I got the first plug out and replaced it with a new NGK plug gapped to 0.7mm. After much frustration I eventually got the 2nd HT lead off, but I can't get my socket to 'lock' onto the plug inorder to get it out and the remaining plugs look even less accessible. The one plug I got out is abit black at the top (probably due to the poor starting and flooding engine) and middle bit is white .

Even with only one new plug in the starting issue is less frequent and the car seems a little better in general and so I'd naturally like to replace the other 3 spark plugs! I was wondering whether anyone had any advice or any tricks to get them out or if theres an easy way to improve access (I think its the multipoint injection engine)?

Thanks!

(To think I thought the plugs looked easier to change than my last car as atleast they face towards the front!)

[Chris Wickers]

I have today just changed mine on the 480.

Getting them out is good fun, and uses a combination of a 'spark plug socket' I bought on its own, and then the relevant extension etc from a socket set.

A simple job still took me a long time and the socket became jammed on the 4th plug! A long nosed mole grip eventually persuaded it to come off!

The difference in performance is amazing, and the lumpiness, and cutting out/poor starting as the engine warms up appears to have gone away.

I suspect the problem was actually incorrect gaps on the old ones which have probably only done about 9,000 miles.

From personal experience I have had 3 or 4 sets of plugs fail on me at around 10,000 miles, and therefore normally try to change them every 6,000.

Good luck.

Chris

[AndyPants]

Thanks for letting me know of your experiences

I ended up asking the garage that was fitting my new cambelt whether they'd fit them and how much it would cost. But they fitted them for free! They had no problems but they were Volvo specialists and I guess they've done it hundreds of times before unlike me lol.

Driven the car a few times since then including yesterday after being left a day or so in miserably rainy weather and the car started up fine first time(by no means near-instant, but I'm thinking its normal for this car). Tried blipping the throttle a couple of times and unlike before the response was instant and the idle was much smoother too. The car in general does feel nippier and more responsive too.

Just need to work out where the jacking points are now so I can change the oil hehe.