Stepper motor V8S
Discussion
Having seen a number of topics covering this subject it suddenly struck me that it could be the stepper motor that makes a 'clicky, unwinding' sort of sound when I turn the ignition off (I hadn't noticed it until recently). Would anyone know if this is the likely cause, and if so:
a) should it make this noise?
b) if not, what I need to do to fix it
c) what'll happen if I leave as is?
MTIA
Steve (V8S)
a) should it make this noise?
b) if not, what I need to do to fix it
c) what'll happen if I leave as is?
MTIA
Steve (V8S)
seb400 said:
Having seen a number of topics covering this subject it suddenly struck me that it could be the stepper motor that makes a 'clicky, unwinding' sort of sound when I turn the ignition off (I hadn't noticed it until recently). Would anyone know if this is the likely cause, and if so:
a) should it make this noise?
b) if not, what I need to do to fix it
c) what'll happen if I leave as is?
MTIA
Steve (V8S)
Yes, that's the stepper motor, although the proper technical term for that noise is 'chuntering quietly to itself'
. It's supposed to park itself each time you switch off - normally you can't hear this over the noise of the engine spinning down but you should hear it if you just switch on and off again.Whats up?
this thread might shed some general info
http://213.52.163.118/gassing/topic.asp?f=13&h=&t=54743
this thread might shed some general info
http://213.52.163.118/gassing/topic.asp?f=13&h=&t=54743
None of the problems discussed here as far as I can recall. Hoses seem airtight, no kink from meter to plenum. Mines got a solid aluminium pipe (about 3ft+ long running from air filter housing to a short flexible section (1ft long) to meter. It's more of a general running issue.
The car starts okay but ticks over a bit high, initially requiring clutch drag to reduce revs to sensible level. Once warmed up (longer than I would have thought necessary - about 10 minutes even in warm weather) the revs return to normal.
The car continually ticks over a bit lumpily (it does have a Kent H214 cam, so to be expected to some degree) sometimes cutting out when slowing to stationary on roundabouts/lights. Engine hunts at tickover between 6-8,000 rpm.
Car is fine under acceleration it's really the initial starting and lumpy tickover that needs attention. Would a new airflow meter be advisable?
Steve
The car starts okay but ticks over a bit high, initially requiring clutch drag to reduce revs to sensible level. Once warmed up (longer than I would have thought necessary - about 10 minutes even in warm weather) the revs return to normal.
The car continually ticks over a bit lumpily (it does have a Kent H214 cam, so to be expected to some degree) sometimes cutting out when slowing to stationary on roundabouts/lights. Engine hunts at tickover between 6-8,000 rpm.
Car is fine under acceleration it's really the initial starting and lumpy tickover that needs attention. Would a new airflow meter be advisable?
Steve
I don't think air flow meters are cheap, so I'd go for a borrow of a known good one first, before going down the buy route 
.
I assume the base idle is correct, the speed sensor is OK, the stepper steps, the wires controlling the stepper are intact, does an ECU reset settle it down for a period
.
The fact that you have a 214 cam fitted, which is a little more agressive than standard and would account for some bad manners pariculary at low revs.
Do you have any other 'mods' to teh engine because you may be getting to the point where the standard chip can't cope (it is pretty much standard rover 3.5 mapping) you may need to speak to Mark Adams to get it looked at and possibily upgraded in that department.
Saying that Mark does do a lot of diagnostic work, not just upgrades and would probably sort it out in pretty short order on the rollers.
All IMHO.....etc
Harry
. I assume the base idle is correct, the speed sensor is OK, the stepper steps, the wires controlling the stepper are intact, does an ECU reset settle it down for a period
. The fact that you have a 214 cam fitted, which is a little more agressive than standard
and would account for some bad manners pariculary at low revs. Do you have any other 'mods' to teh engine because you may be getting to the point where the standard chip can't cope (it is pretty much standard rover 3.5 mapping) you may need to speak to Mark Adams to get it looked at and possibily upgraded in that department.
Saying that Mark does do a lot of diagnostic work, not just upgrades and would probably sort it out in pretty short order on the rollers.
All IMHO.....etc
Harry
Thats a tad high mate! 
Well spotted keithboy, for ,000 read 00 
.
Thanks HarryW, maybe that would be the best suggestion. I did have to replace the airflow meter on my old 350i previously which had similar problems. Cost was/is around £150. It's just an inconvenience at present, but one I'd rather not have. The engine rebuild was done to Griffith 400 spec and by looking at the invoice seems standard as far as I can tell with lots of O.E. parts.
. Thanks HarryW, maybe that would be the best suggestion. I did have to replace the airflow meter on my old 350i previously which had similar problems. Cost was/is around £150. It's just an inconvenience at present, but one I'd rather not have. The engine rebuild was done to Griffith 400 spec and by looking at the invoice seems standard as far as I can tell with lots of O.E. parts.
I got so fed up with the erratic idle on my V8S that when i fitted the ACT plenum I blanked it off - guess what? .. the idle still hunts all over and it's not the stepper causing it at all .. seems every so often the ECU throws a wobbly and the mixture goes slightly richer bring the idle up a few hundred revs, then returns to proper switching and the idle goes back down again . Not too bothered about it though and at some poitn an aftermarket ecu will go on anyway.
The ACT stuff looks cool even with my budget ford throttle body and lots of aluminium duction everywhere
The ACT stuff looks cool even with my budget ford throttle body and lots of aluminium duction everywhere
Yes Mark can look at what the ECU is doing in real time on the lap top, which is very handy because even with a good ECU the faults are not always fully recognised and logged.
First thing Mark will do is run a full disagnostic on the ECU which highlight any problems inherent with it, then he'll check it out with the engine running then finally on the move (rolling road) if there's a problem anywhere in the system he'll identify in short order.
Then again knowing lumpy cams can have some bad manners and yes, as Joolz pointed out, the ECU does have a funny 10 secs every now and then.
Give him a ring for a chat, btw he is very difficult to get hold of sometimes.
Harry
First thing Mark will do is run a full disagnostic on the ECU which highlight any problems inherent with it, then he'll check it out with the engine running then finally on the move (rolling road) if there's a problem anywhere in the system he'll identify in short order.
Then again knowing lumpy cams
can have some bad manners and yes, as Joolz pointed out, the ECU does have a funny 10 secs every now and then. Give him a ring for a chat, btw he is very difficult to get hold of sometimes.
Harry
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