Tricky-Ricky

If the ignition is off there is no power to the MAF anyway, so just unplug the old and fit the new.

If the clutch pedal has previously adjusted due to being worn, when fitting a new clutch plate its possible that the adjustment has caused the master cylinder to not return back far enough to uncover the fluid transfer port, so there is no fluid, or very little being drawn into the MC so its not moving enough fluid.

The sender doesn't need a voltage its just a variable resistor, check the manual, the display however I would suspect does have a voltage supply.

could be the yaw sensor or an ABS sensor failed.

Fuel level sensor is resistance based not voltage.

Never buy a car from this person!!!

Who made that....liberace's jeweler.

I strongly suspect that its going to be a Nissan only part and that its one piece IE pulley with bearing. Have you tried the traders here?

Sorry you said right,the one on the right is also an idler with a bearing inside, but not adjustable.

Its the power steering pump, and the rusty one underneath is the tensioner/idler, which has a bearing and which is used to adjust the belt tension, you should be able to twist the belt at the longest run about 45 degrees if its tensioned correctly.

Do you have air con? and are you talking removing yours? unless your losing something its not possible to fit a shorter belt, I would look at either the idler/tensioner pulley bearing or possibly the alternator or power steering pump, the over tight belt tension wont help things.

Nothing like a badly out of balanced wheel to quickly kill a wheel bearing.

Sounds like a wheel bearing on the way out to me.

Iridium plugs where developed for extended service life and for where the plugs are difficult to get at, just like the platinums that they replaced, they are supposed to last up to 60K in ideal conditions but I would say 30K is a good time to change, personally I just use copper core and replace after 6K and they are about 1/6th the price and do exactly the same job. But you end up paying the same overall? True but I like to check the condition of my plugs a bit more often than 30+K so may as well change them for the sake of a tenner, also because I come from turbo cars I shy away from iridiums anyway because they don't hold up to det very well.

Iridium plugs where developed for extended service life and for where the plugs are difficult to get at, just like the platinums that they replaced, they are supposed to last up to 60K in ideal conditions but I would say 30K is a good time to change, personally I just use copper core and replace after 6K and they are about 1/6th the price and do exactly the same job.

The Japanese equivalent of the MOT is very strict, so most people will just buy a new car, also its considered bad luck to buy/own a used car, you inherit the last owners bad luck.

One thing that's always puzzled me with using ARC Catch cans, is that they are pretty shallow and if your engine generates a lot of water vapor along with the oil mist, during hard cornering you could end up with the contents being sucked back into the intake if you have them connected as intended, are they extensively baffled inside to prevent this happening?

If you have suddenly got excess movement in the clutch pedal then its either going to be fluid loss or a mechanical problem with the clutch mechanism or the clutch itself, the DMF wont cause excess movement, it will however make noise when taking up drive or on coming off the throttle when in gear.

Sorry to hear this mate had damage from drunks where I used to live, if you cant polish it out, PM Zmanalex on here he breaks Skyline 350GTs.

Just out of curiosity hows the drive train holding up? that's around 140ftlb in less than 500RPM?

Taking the mic! 1/2 hour tops, compression test is just a basic check to see if one cylinder is down, and so could indicate a badly blown HG, broken piston ring, badly seating valve, or worst case scenario hole in piston. However I recommended a leak-down test as this will differentiate between a valve seat problem and ring seal/head gasket, before just dismantling things to find the cause. But based on what you have said about the engine overheating I would be looking to replace the head gasket/s.

Compression test being done this week A few weeks back I was stuck in heavy traffic for a while and the fans packed up , coolant went everywhere needless to say engine got very hot and I was towed home , thinking this excessive heat may have fried the piston rings ?? I think its more likely you have blown a head gasket fella, also get a proper leak-down test done.

Re the tappets, they are solid not hydraulic Sorry! why do I keep thinking the VQ has hydraulic lifters!

I have used poncams on a different engine, if they say that they will fit with no problems they should be fine, springs shouldn't be needed, as the poncams are designed especially for minor power upgrade to std motors with hydraulic lifters, I strongly suspect you will need to use a little more RPM to achieve the extra power/torque though, I did despite what they say, it seemed to push the ideal change RPM up by about 4-500 rpm.

Hydraulic tappet failed/not pumping up, but there is also an underlying noise that sound very much like a big end knock to me, does it become resonant when you hold the revs at around 3-3,500?