Matt C Posted May 19, 2009 Author Posted May 19, 2009 Tim is correct, its the cam profile/duration that changes not the cam lift. If the ECU sees an issue of any kind, it will not vary the duration and hence the need to limit the revs. Cam profile not changing and rev lower limit go hand in hand. After interrogation yesterday via diagnostics machine... all sensors are ok and there are no fault codes logged. The correct signal is going to the solenoids from the ECU, and the solenoids are working (via the diagnostics system check). The garage swapped them round and tried new ones as well just to be sure. The HCU has been removed and cleaned - thats all working fine. So basically, the piston inside the HCU is moving the rack and pinion shaft to the VVC unit fine, but the cam sensor is not seeing a change, hence the issue is with the unit itself. As soon as I can get the car to the garage (rear clam is off now) they are going to look at the VVC timing. As the units were working before the hgf, I reckon its the timing that will be out rather than the units being faulty.
Guest Glen Posted May 19, 2009 Posted May 19, 2009 Thanks lummo, someone else gets it! I know that solenoids are not variable devices, but by energising one or the other the actuator position is changed. And as the actuator is constantly changing to vary both the inlet value opening time and period, then the solenoids will be constantly be being switched on to achieve this - but only one of the solenoids in on at any one time.
Matt C Posted May 19, 2009 Author Posted May 19, 2009 We have all got it right, just described it in different ways - Tim and Lummo have said the same thing, but Tim has described how the input shaft is moved, as Lummo has described what the VVC does. Essentially, back to the point, if the rev limit is active, then the VVC is not moving at all.
TheRon Posted May 19, 2009 Posted May 19, 2009 Good news on the investigation front - at least you're away from the fiddly electronics and back into good old mechanicals now !
Guest Glen Posted May 19, 2009 Posted May 19, 2009 Matt, although it's possible that mine is also mechanically faulty as it's also had the head off, I'm beginning to suspect we have different faults. The timing marks have allegedly be check on mine (as per this) by a garage and it was OK. Does yours show as a cam sensor fault then if the cam sensor is not picking up the reading?
Matt C Posted May 19, 2009 Author Posted May 19, 2009 Cam sensor is ok - no fault. I know its ok aswell as the idle speed is 800rpm (ish) when warm. If it was faulty idle would be 1000rpm+. I have read somewhere that the holes mentioned in that link are not a particularly reliable way of checking VVC timing. Not usre how true this is.
Matt C Posted May 19, 2009 Author Posted May 19, 2009 Are any of the engine breather pipes split? Not as far as Martin R and myself can see. Although would that affect the mechanicals/VVC? As long as the ECU sees the right signals from the sensors, all should be ok.
Guest Glen Posted May 19, 2009 Posted May 19, 2009 Cam sensor is ok - no fault. I know its ok aswell as the idle speed is 800rpm (ish) when warm. If it was faulty idle would be 1000rpm+.I have read somewhere that the holes mentioned in that link are not a particularly reliable way of checking VVC timing. Not usre how true this is. OK - cam sensor makes sense. If it's true about holes not being reliable (and I don't doubt it) the I'm back to square one not knowing if it's the ECU or the mechanicals again.
Matt C Posted May 19, 2009 Author Posted May 19, 2009 OK - cam sensor makes sense. If it's true about holes not being reliable (and I don't doubt it) the I'm back to square one not knowing if it's the ECU or the mechanicals again. Remind me... have you had it plugged into Testbook diagnostics? Edit - just read your first post... maybe it is the same issue as mine? Only reason I think it is not reliable is you have to use a jig to set the unit. Not possible without it.
Ladders Posted May 19, 2009 Posted May 19, 2009 Not trying to point out the obvious, but is it worth taking it to Dave Andrews?
Matt C Posted May 19, 2009 Author Posted May 19, 2009 Not trying to point out the obvious, but is it worth taking it to Dave Andrews? Dave is sure he has done it right. So going for a local second opinion who specialises with VVC.
Matt C Posted May 21, 2009 Author Posted May 21, 2009 Its fixed!!! Yeay!!!! The units were removed and assembly jigs fitted, re-assembled, and all is working again. Seems like the units were not timed correctly but we can not but sure. Off to get it shortly.... Glen, speaking to the garage about yours, they say the timing can not be checked in situ, but needs removing and the correct assembly jigs fitted to get it right. Seems the holes mentioned are not used by Rover when setting.
Martin R Posted May 21, 2009 Posted May 21, 2009 Great news Matt That garage is a very good find for anyone with a VVC engine as well.
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