Evening one and all,

 

I'm at my wits end in trying to figure out what is causing my engine to "rattle" under light load ... At first I thought it was detonation but a quick visit to AndyP and a timing adjustment ruled that out. It is now really starting to p*ss me off intensely.

 

Here's the situation:

When the engine is at operating temperature (i.e., warmed up propperly) there is a definite rattle when the auto box shifts into fourth gear and subsequently into OD. The rattle is much more pronounced and louder in OD but is still audible one gear lower. The only analogy I can come up with is the sound an engine makes when you're driving along in too high a gear for the speed you're travelling at (in a manual transmission car). For example, pulling away in third gear from a traffic light. You'll hear the valves flutter which stops when you shift down and engage a lower gear.

 

On the Z32 service manual CD (Thanks Senna) there is a mention of a "valve timing control solenoid valve". Can this be the cause of my problems? I.e., my valve timing is off in higher gears due to poor camshaft timing or something like that? Can this be easily changed by myself or is it an "engine out" job as Nelson would have me believe is require for an oil change ...?

 

Ahhhggrrrrr ... I'm really struggling with this. I want to have this problem sorted before I install my JWT chip and boost jets. They've been sitting in a drawer for over a month now and I can't wait to put them on!

 

Anyway, many thanks in advance for all you words of wisdom.

 

Cheers

 

Danny --> off to look at the chip that will make motoring sooooo much more fun!

Danny,

Have you got Jeff to give you a 2nd/3rd opinion ? I REALLY don't think its pre-ignition as although it is happening at the right sort of time, it's really not a harsh enough noise. Kind of like a reasonance buzz rather than a rattle of pinking.

Why don't you try getting that chip in as it'll do no harm at all.

Forgot to say but Jeff knows how to check the valve timing. Sure it's nowt to do with that though as you'd get all sorts of funny symptoms.

Thanks Andy - I'll be seeing Jeff in a couple of days and ask for a second opinion.

 

Cheers mate!

 

Danny

Hi Danny,

This might sound a bit daft and you might have tried it already, but have you checked your transmission fluid? I had a similar problem with my old Lexus, and it turned out that I was using the wrong viscoscity transmission fluid apparently different fluids change viscoscity at different temperatures which can cause this rattle,

Just something to try, hope this helps,

 

Brian

 

(P.s will mail you when I am coming to the UK, was caught to go to Budapest next week so will know after that)

Cheers Brian! Will have a look at it when it stops raining over here. Last time I checked the trans fuid it all looked perfectly okay but then again, I don't know when it was put in or what type they used ... Might be a good idea to change the fluid all together for the propper stuff.

 

Budapest is lovely - have been there several times. If you need any tips on where to go (eat, hotel, sight seeing, etc) let me know.

 

Cheers mate!

 

Danny

need tips, need tips!! I know absolutely nothing about Budapest! am staying in the Gellert hotel, any good restaurants/clubs/things to see?

Cheers Danny!

Brian