Suspension gone harsh since battery disconnect

[Delboy]

Good investigation there.

As to your heights it possible someone has adapted the suspension and offset the figures to fool the ecu into riding lower, but to rectify you need to do the calibration from scratch.

https://www.youtube.com/watch?v=o2aeQ6bhu-Y

[Architex_mA8tey]

Great write up thanks and good information for all - added to sticky

[Mechcanico Lee]

Originally Posted by Delboy

Good investigation there.

As to your heights it possible someone has adapted the suspension and offset the figures to fool the ecu into riding lower, but to rectify you need to do the calibration from scratch.

https://www.youtube.com/watch?v=o2aeQ6bhu-Y

Yes , had this in mind ......I do the same on range rover sports and the discovery 3s when the height potentiometers have gone slightly off on the voltage range , just trick the ecm with a different actual reading to get the car balanced .

Thanks for the positive comments , I've been spannering on cars for 30 years now and you do really learn something new everyday , no one knows it all but as a group the knowledge all comes together , I've learnt loads since coming on here , there's some very knowledgeable folk for sure .
I work on everything all models but my favourite field is non intrusive diagnostics so I use a scope quite a lot and use 'in cylinder pressure transducers ' to diagnose say a timing chain stretched or jumped chains or cambelts , don't even take a rocker cover off to diagnose them with the correct tools , it's an interesting field , more enjoyable than fitting discs and pads .... more brain testing .

Ray. going to see if I can get to the owners meet this year , just looking at the pictures of 2015 ,food , beer , car talk , enjoy all that

[Delboy]

Now this is an avenue of diagnostics I would like to learn more about, so if your willing to lead I'm willing to follow.

I have a dual channel scope already that i used in the past for simple things, also seen videos for using it to to test for sticking injectors but never had need to put into practise yet but I'm sure theres more that its capable of like you have hinted too.

[Mechcanico Lee]

We have a 4 channel pico , it's a superb scope Im only touching the tip of what's its cable of , there's a great scope forum it's called Auto Nerds .... it's American based so you have put up with , fender , buddy , and muffler a lot but there into it big time .

As for injector testing using an amps clamp with the scope shows you more than the volts and duration wave forms , it shows better how the amps 'push ramp 'is trying to un stick the injector pintle , I'm no expert by any means , you have to use it to learn more .


Going to bore the hell out of you all now , but here's how to tell when you have cambelts jumped or chains stretched or dowel or woodruff keys ' ridden over '







Blue trace is crank shaft sensor pick up on flywheel , normally around 60 teeth segments less the ' missing tooth ' segments that the ecm uses to reference top dead .

The red trace at the top is the square wave ( Hall effect ) from cam sensor , so you are looking for how many teeth from missing tooth segment to cam sensor switch on time .

The brown / yellow trace is the in cylinder pressure transducer , the peak is max pressure in the cylinder , it all looks a bit confusing dun it hehe !!

Cut to the chase here .....this is a crank pulley that has ridden over woodruff key , no taking engine apart , no cam covers off , all diagnosed from ecm wiring multi plugs and of course having scope traces from a good engine which I can source from auto nerds library or other sources .

You all fell asleep now zzzzzzzz hehe !!

[Delboy]

Originally Posted by Mechcanico Lee

We have a 4 channel pico , it's a superb scope Im only touching the tip of what's its cable of , there's a great scope forum it's called Auto Nerds .... it's American based so you have put up with , fender , buddy , and muffler a lot but there into it big time .

As for injector testing using an amps clamp with the scope shows you more than the volts and duration wave forms , it shows better how the amps 'push ramp 'is trying to un stick the injector pintle , I'm no expert by any means , you have to use it to learn more .


Going to bore the hell out of you all now , but here's how to tell when you have cambelts jumped or chains stretched or dowel or woodruff keys ' ridden over '







Blue trace is crank shaft sensor pick up on flywheel , normally around 60 teeth segments less the ' missing tooth ' segments that the ecm uses to reference top dead .

The red trace at the top is the square wave ( Hall effect ) from cam sensor , so you are looking for how many teeth from missing tooth segment to cam sensor switch on time .

The brown / yellow trace is the in cylinder pressure transducer , the peak is max pressure in the cylinder , it all looks a bit confusing dun it hehe !!

Cut to the chase here .....this is a crank pulley that has ridden over woodruff key , no taking engine apart , no cam covers off , all diagnosed from ecm wiring multi plugs and of course having scope traces from a good engine which I can source from auto nerds library or other sources .

You all fell asleep now zzzzzzzz hehe !!

Nope still awake, I'll be sure to check out the nerds

[tc4332]

Lee,
This is all good stuff, Luv it.
I have an ex military twin trace scope, not the latest and greatest but still excellent for purpose.
My problems are of age, grey matter is much slower than it used to be, and memory does fail me terribly. My old system of instant recall from the mind pigeon holes fails rather spectacularly. By the time I've recalled what I need I have forgotten why I needed it
It would be nice if you manage the annual meet. Of course TinTin will be speaking up soon to organise another local gathering.

[Mechcanico Lee]

Ex military scope eh ?? was that the scope you used to decipher the enigma machine it the war Ray ???

[tc4332]

Nah Lee, twas a year or three before then.
I was stationed darn South near Hastings. We were trying to design the optimum arrow trajectory for maximum effect, but the bloodie frenchies beat us to it.

They got our Harold in the eye

[BADES]

Hey Lee,

I had a similar problem in the wife's Q7 - its been a while and is still not gone back to 'normal' - (but she has driven in comfort ever since)

Do you think disconnecting the battery and reconnecting would be the best way to go ? any suggestions ?

i'll try to stay in dynamic ride today as i've got the car for a few days, to see if that makes any difference.
Thx
Bal.