Re: Punto 75SX Eratic Tickover

Hi Nick

Many thanks for the information.

My 'tame' mechanic has now helped me have a go at this but we couldn't 
remove the control valve as one of the screw heads became mashed. So we 
tightened the unit up again and gave all connections la****ngs of WD40 and 
it's now running better, not perfect, but loads better (good enough to 
sell). This seems to confirm it may be the idle control valve so I am now 
going to replace it. I've found them on eBay for £20-25 so it's worth a
try. 
Although it seems tricky working out which one to get. Have tried reading 
the part number on the side of the existing valve but it doesn't match
what 
the 2 companies state on eBay.

I'll update you when I sort it out.

Thanks again.

Rick



"Nick /////" <reply@[EMAIL PROTECTED]
> wrote in message 
news:46fad340$0$56163$7b0f0fd3@[EMAIL PROTECTED]
> "Baldrick" <rick.hardy@[EMAIL PROTECTED]
> wrote in message 
> news:G8zKi.34962$ka7.15159@[EMAIL PROTECTED]
>> Hi Nick
>>
>> Yes, it's states Multi-Point Injection on black plastic oil filter 
>> housing and also MPI on the ECU. The 'log' book says 1242 cc.
>>
>> Rick
>>
> Ok.
>
> Without digging deeper I'm now assuming that the 1.2MPI is essentially
the 
> same as the Magnetti Mirelleli MPI unit fitted to the Tempra 1.8ie.
>
> Follow this:
>
> Locate the manifold inlet tubes at the cylinder head itself.  Follow
them 
> back and possibly upwards.  They will probably all meet/interface with a

> large chamber/body that joins them together.  This is the plenum
chamber. 
> At one end of this is the throttle body.  After the throttle body is a 
> large tube assembly that leads to the air filter and beyond.  Around 
> either side of the throttle body there may be two hoses (obe either
side) 
> that lead off to a valve, called the air bypass valve.  This may be 
> located at the end of the cylinder head above the gearbox and between
the 
> battery box.
>
> The purpose of this valve is to act as a variable bypass around the 
> throttle plate thus adjusting the engine idle revs.  They are know to 
> stick with age.
>
> Here is the contents of a post I have made on this in the past. (22
April 
> 2007)
>
> 1) Check for leaks/cracks etc in all air hoses attached to the inlet
> manifold.  This include the brake vacuum hose.  Also operate the brake
> pedal and listen for engine speed or note changes.
>
> 2) Sticking idle control solenoid - this could be either a mechanical
> operation on the throttle butterfly or an air bypass valve.  If you have
> an air bypass solenoid then one should service this as sticking is a
> known problem.  Easy to do.  Just remove the valve and inspect inside.
> Gently remove any deposits.  Flush / fill with WD-40 and agitate.  If it
> is really dirty then wash out with white spirit, dry and give a very
> good soak with WD-40.  Another trick is to allow the engine management
> system to modulate the valve when you have WD-40 in it.  Easy to do by
> only making the electrical connection, fill with WD-40 and hand/finger
> seal the hose connection points and then get somebody to turn the
> ignition on (DO NOT START).  The ECU will open and close the valve a
> couple of times.  Repeat ignition on/off cycle a few times.
>
> The valve is officially called VAE Valve.
>
> 3) Incorrect static air bypass setting. Tempra Magnetti Marelli fuel
> injection systems had this identified by a grub screw and locking nut
> located on the throttle body. This sets a minimum air bypass and thus
> idle speed so that the air bypass valve has a nominal point about which
> to  operate.  To set this up one has to disconnect the electrical
> connection to the air bypass valve.  The car should not stall be yours
> may.  If this happens then reconnect the valve.  Adjust the grub screw
> out.  Initially nothing may happen as the bypass valve will
> automatically compensate for your adjustment.  Get the revs to about
> 1000rpm.  Now you can disconnect the valve connector and proceed to
> adjust the grub screw till the revs are about 650 to 700rpm. Now connect
> the valve connector again and the revs will briefly rise to about 1200
> rpm or so and then drop back again to about 850 rpm.
>
> Lastly blip the throttle and check that the car does not stall or idle
> too low.  Test drive as well.  You may find that you have to have a
> couple of cycles in setting the bypass grub screw.  Setting too low revs
> will cause stalling etc. and too high will mean too fast and idle.
>
> 4) If all of 3) still does not work to your satisfaction then there was
> a Fiat service bulletin that modified the original set-up as in 3) to
> actually set the grub screw get engine revs of 900rpm (or as low a you
> can get to 850rpm) so that when the VAE valve electrical connection is
> removed/connected there is NO variation in rpm.  I never had to do this
> as I found that the method and settings in 3) was perfectly OK for my
> Tempra.  You may find that you need to go with this 4) method.
>
> Lastly if the Marea uses a mechanical solenoid directly operating on the
>  throttle body butterfly (Most Fiat single point injection systems like
> in the Tipo use this method) then just like the air bypass grub screw in
> 3 & 4, there will be a similar grub screw to set the base throttle
> opening from which the solenoid lifts the engine revs.
>
> I leave the rest for you to sort out :-)
>
> Nick /////
>