My 155 seems to be giving me all the headaches in the world although I treat her with respect and cherish her like a girlfriend!!
First off, a bit of background info:
I seem to have suffered all of the problems of the entire forum all together and all in one go!!!
At 44k mls I burnt-out a valve on cylinder no.3 whilst doing 130mph..
I traced this by first disconnecting each injector to see whether one of these had gone even if it is very unlikely since they are very reliable.. it could have been an electrical gremlin but this would have been recorded by the ECU; anyway, cylinder no.3 seemed to be the problem) I did a compression test on all four cylinders.. very interesting readings.. they seemed to vary a lot between cyl to cyl and no.3 registered a big fat zero!!! OH NO!!! I proceeded taking the cyl-head off and got to work!!! Fortunately for me it looked like I just burnt out a valve and the chunks went through the exhaust port rather than in the chamber so the piston was fine. I put the head and all ancillaries in the hot-wash to loosen up the carbon deposits on the head; everything came out clean like the day it was first assembled. I cleaned the pent-roof chamber and exhaust ports with a brass drill-bit this looked fine. All the valves were cleaned with a wire brush on a bench grinder and then inspected: I had to replace the remaining three valves above cyl no.3 since they were heavily pitted on the valve to valve seat interface (chamfered edge of the valve). I then lapped in all of the valves once again (that took me 16hrs alone!!!). I proceeded to change all 3 engine belts and the two adjustable pulleys since these seemed to be a known weakness of the car (PS if one isn't made of white-plastic and the other hasn't got a thin-blue ring around its circumference I would suggest you change it pronto!) I inspected the pistons' crowns and the cylinder sleeves and they looked in very good condition. I proceeded reassembling the head with fresh cyl-head stretch-bolts (highly recommended!) and then had a look at the cams... Oh no... both of them looked worn (all the lobes were quite squared off, purticularly on cyl-no 3). I had to change both cams and hdraulic tappets for a 2nd hand set. The cam-variator was also replaced since this seems to be another known weakness (if the engine sound like a diesel when you lift-off the throttle at high rpm in 1st or 2nd gear it is best to replace it). The engine was then professionally timed by a friend of mine who had the required cam-locking caps etc..
I sandblasted and resprayed with black hammerite all of the coolant and powersteering pipes. I replaced the steel Modine oil cooler for a later Aluminium one (more efficient and won't corrode) since the watersprays killed-off the steel one as a result of the front plastic airdam cracking and coming detached from the vehicle. This was never replaced since it would have gone again due to the combination of speed bumps and how low it sits!
The oil filter, air filter and fuel filter were changed for new, genuine items.
Everything was put back together along with brand new water hoses (all of them!). I used Oetiker clips instead of jubilees since these do not seal evenly around the circumference of the hose and might actually cause leaks and damage the hose itself. Oetikers are more expensive but they offer a constant 360degree seal along with a spring so they can cope with expansion and contraction of the hoses due to the varying temperatures of the coolant.
All lubricants were changed for recommended items except for the engine oil since I preferred to use a fully sinthetic Castrol RS 0W-40 (I do NOT recommend MOBIL). I also used ZX1 Extralube additive to all fluids including the coolant (PS dilute coolant with de-ionised water if you don't want your water pump to look like you kettle!).
Finally the engine is running again with brand new sparkplugs too!!!
The engine sounds wonderful and feels a lot smoother, quieter and definetly feels well put together (must have been a good job then!!!) An oil leak developed from the corner of the aluminium cam-cover. This turned out to be another well known problem... The cover is apparently not very strong and if you overtighten in it will crack very easily. What I've done is I replaced it with a plastic 156 cover instead. The only modifications you need to carry out are buying new oil venting recirculation pipes (these come out at different angles from the new cover. These are found on the right-hand corner of the cover and go the the plastic ribbed induction sleeve connecting to the throttle body and the otherone goes after that if I remember correctly. If you are bothered by the non appealing look of this new modification you can buy the silver plastic beauty cover that sits on top of this (just like the 156) but it will require cutting away a small section of it on the top right-hand corner to allow the top oil vent pipe to come out where it should.
This is where the electrical grief began.
Please bear in mind that I cannot do anything that is electrical since it is all a mistery to me so please help if you can!!!
Item 1. The oil temperature sensor on the dash never registers above 60 although this should tipically always be 10degrees higher than the water temperature. My water gauge during winter usually sits at 70 but during the summer it is always between 80 and 90.
Has anyone got an idea of what it could be? Is it a bad sender that needs replacing?
I had a look at the connections but they all appear to be fine.
Item 2. My H1 12V headlamps (both dipped-beams and fog-lamps) seem to be burning out at 6 to 12 months intervals. I tried RING Ice Blue replacements but these have not cured the problem.
Item 3. The fuel injection system warning light has started lighting up every three to four days. When I went for a trip on the motorway it just stayed on all the time.
The revs dip just below 800rpm and then once the light goes out rise to the more usual 1000rpm. It seems to be going in limp-home mode. I was told that this could be due to the timing sensor on the exhaust camshaft pulley (apparently another known weakness).
Has anybody had the same fault?
Have you fixed it? How did you do it?
Item 4. My engine oil low level light came on and went off after 10sec so I immediatly topped the oil up to the max. This light still came on twice and now the one on the check panel above the radio is also permanently on.
Any ideas guys&girls?
Item 5. My power steering pump every now and then makes a terrible whining noise and keeps on doing it until it stops all of a sudden. It seems to be working ok but it just sounds like I've got a hamster running inside a wheel under my bonnet!
Item 6. When I first start the engine from cold, the starter motor engages and the engine turns-over but when I release the ignition hey it doesn't seem to disengage properly and it makes a horrible noise for a second or two and after that it's fine.
Has anyone had the same problem?
Item 7. I seem to have blown the baffles in the exhaust centre silencer box. Is this common? How expensive are they to replace? I think I would prefer to completely remove this and put a straight through pipe section instead. Has anyone done this already? Is the vehicle very noisy after such a modification?
I am sorry it took so long but I hope this background info will help out other people along with giving you enough info to help me diagnose my problems.
Many thanks guys,