Club G40 Forum

Technical => Engine and Transmission => Topic started by: Spacemonkey1993 on January 30, 2011, 08:05:30 PM

Title: Engine won't start
Post by: Spacemonkey1993 on January 30, 2011, 08:05:30 PM
Basically my g40 wouldn't start today and i cannot work out why. i was running perfectly yesterday, throughout the night at lakeside but today all it is doing is turning the starter motor. the battery is fine and ive tried bumping it but nothing is working. ive replaced the distributor cap and the spark plugs. It has petrol in the tank but the problem must be something simple as it has always started first time.... any help would be very appreciated!

cheers,
jamie.
Title: Re: Engine won't start
Post by: Jezza-7 on January 30, 2011, 08:08:40 PM
Is the fuel pump priming?

Title: Re: Engine won't start
Post by: Spacemonkey1993 on January 30, 2011, 08:10:44 PM
how can i tell?
Title: Re: Engine won't start
Post by: Jezza-7 on January 30, 2011, 08:14:06 PM
When you put the key in, turn the key but dont start and listen for the pump at the rear. Sometimes its best to get a friend to turn the key while your under the pump and listen for it.
Title: Re: Engine won't start
Post by: Spacemonkey1993 on January 30, 2011, 08:44:39 PM
Thanks, it is working.
Title: Re: Engine won't start
Post by: scotsjohn on January 30, 2011, 09:27:30 PM
Are you getting a spark?
Title: Re: Engine won't start
Post by: Spacemonkey1993 on January 30, 2011, 09:36:42 PM
Nah no spark from any plugs also the king lead doesn't spark when I hold it to earth
Title: Re: Engine won't start
Post by: PeteG40 on January 30, 2011, 09:38:35 PM
sounds like yr coil
Title: Re: Engine won't start
Post by: Spacemonkey1993 on January 30, 2011, 11:37:35 PM
but the king lead which is before the coil doesnt spark when i hold it to an earth?
Title: Re: Engine won't start
Post by: PeteG40 on January 31, 2011, 08:22:21 AM
the king lead goes from the coil to the dizzy, which then puts power/sparks down the leads to the spark plugs.  if the king lead is not connected to the coil then it won't spark!

sounds like you're holdinh the king lead from dizzy to earth - which means it'll have no power to it
Title: Re: Engine won't start
Post by: hayesey on January 31, 2011, 09:13:12 AM
the coil is the square thing the king lead comes from.  You are probably thinking of the distributor.
Title: Re: Engine won't start
Post by: Spacemonkey1993 on January 31, 2011, 10:16:19 AM
ahh ok ill try that then, thanks
Title: Re: Engine won't start
Post by: Spacemonkey1993 on January 31, 2011, 06:08:11 PM
ok turns out that my coil isnt the problem as i just fitted a brand new one. so it must be either king lead (unlikely) or the distributor?
Title: Re: Engine won't start
Post by: Jezza-7 on January 31, 2011, 10:24:29 PM
Hall sender?

I had a very similar problem once.
Title: Re: Engine won't start
Post by: hardchargin40 on February 01, 2011, 08:12:10 AM

you've checked your fuses I assume?  Also check the two 3pin connectors by the coil are correctly on.


Then after that, probably hall sender as Jez said, common polo problem.
Title: Re: Engine won't start
Post by: Spacemonkey1993 on February 01, 2011, 12:50:29 PM
Yeh it's not a fuse and I've checked all the plugs. But i have no idea what a hall sender is lol?
Title: Re: Engine won't start
Post by: hardchargin40 on February 01, 2011, 01:06:33 PM
Its in the distributor.  I think bosch do replacements - many moons ago but may still.  That or a new distributor needed.  May be wise to get out the multimeter first though before shelling out.
Title: Re: Engine won't start
Post by: hayesey on February 01, 2011, 01:12:23 PM
read the engine diagnosis thread in FAQ. 
Title: Re: Engine won't start
Post by: hardchargin40 on February 01, 2011, 01:32:26 PM
Dug it out for you...

- hall sender: to test disconnect the ignition coil connector, unbolt the distributor from the engine but leave the wiring loom connector connected to it (you can take the cap off if you want).  Now turn the ignition on but do not try to start the engine.  Turn the distributor by hand, every time the trigger wheel inside goes past the hall sensor, you should hear the injectors fire and the fuel pump run momentarily.  I can't remember if it operates leading edge or trailing edge but it doesn't really matter.  Just check that turning the dizzy by hand makes the injectors and fuel pump fire.  The part number on the correct dizzy should end with a "P", others will have incorrect trigger wheel spacing and will cause running problems.  You can also use a dizzy from an 8v mk4 polo which are identifiable by having the hall sender connector on the back (as you look at the engine from the front of the car) whereas the original mk3 polo ones are on the top.
Title: Re: Engine won't start
Post by: Spacemonkey1993 on February 01, 2011, 03:25:27 PM
(http://sphotos.ak.fbcdn.net/hphotos-ak-ash1/hs785.ash1/167567_10150172537838696_757493695_8503923_5191528_n.jpg)

this is the hall sender yeh? the bit below the plug...
Title: Re: Engine won't start
Post by: hayesey on February 01, 2011, 03:29:40 PM
yeah, the sensor and connector are all the same piece of plastic.
Title: Re: Engine won't start
Post by: Jezza-7 on February 01, 2011, 05:23:48 PM
You can buy new hall senders but there around £60.
Title: Re: Engine won't start
Post by: Spacemonkey1993 on February 01, 2011, 05:25:56 PM
right its not that because i got a dizzy and tryed it. ive tried everything i can think of so ill take it to a garage tomorow
Title: Re: Engine won't start
Post by: hardchargin40 on February 02, 2011, 08:06:29 AM
Cam and ignition timing all set right?

Hope you get it sorted, fingers crossed it just something thats been overlooked.
Title: Re: Engine won't start
Post by: Spacemonkey1993 on February 02, 2011, 08:23:15 AM
Yeh hopefully, thanks for all the help anyway
Title: Re: Engine won't start
Post by: scotsjohn on February 02, 2011, 05:11:22 PM
Fingers crossed it's not an ECU fail. Cheerful fucker amn't I.