Intermittent starting

[spudboy6]

My 1.8 8v SE has a gremlin under the dash ,

So I drove home , stalled it and turned the key again, and all the lights dimmed and the car turned over , then stopped.  Then turned over then stopped an this carried on and it never started , almost like a flat battery but let me tell you now its been tested its fine !

Went out to the car 15mins later first turn of the key and its started after a few turns over and smelt of fuel but went straight away .

But does it at times I get in it turn the key and nothing , car turns over slows down speeds up then nothing .

It's has had an ignition switch  ,

Any ideas ? No fault codes in vagcom , its had the rubber gasket on the throttle body and new leads new dizzy and rotor arm ect

Thanks

[itavaltalainen]

check if you get signal from the hall sender unit when you crank, you can use a cheap LED test lamp or mini DSO, it should flash up nicely. I think the middle pin is the signal line...
if not then you found the culprit.

although strong smell of petrol after starting might suggest that it's not firing, then check that you got a spark. if not i would think coil....

[spudboy6]

check if you get signal from the hall sender unit when you crank, you can use a cheap LED test lamp or mini DSO, it should flash up nicely. I think the middle pin is the signal line...
if not then you found the culprit.

although strong smell of petrol after starting might suggest that it's not firing, then check that you got a spark. if not i would think coil....

I think the fuel smell was because where it half cranked so many times as it stopped in the most unpleasant place and I needed to move it , but possibly the coil but that wouldn't explain the not turning over ,


I do get this code

00515 camshaft position hall sensor g40 03-00 no signal

But I hear they all say this when vagcom is used with engine off ?

To check that do I stick my LED tester in the back of the plug on the bottom of the distributor where the plug is on the side ?

[itavaltalainen]

Which 1.8 have you got??
The Mk3 ones have no cam sensor 

to test hall sender you need to put the LED's positive input to the back of the middle pin... other one to ground. might be worth checking that you get 12v between the outside pins, but can't remember which is gnd.... but with digital multimeter doesn't really matter.

the hall sender fault on vag com is normal if the engine is not running... since it has no cam shaft sensor it has no reference for engine speed, so if it's not turning the ecu assumes it's faulty

[spudboy6]

Which 1.8 have you got??
The Mk3 ones have no cam sensor 

to test hall sender you need to put the LED's positive input to the back of the middle pin... other one to ground. might be worth checking that you get 12v between the outside pins, but can't remember which is gnd.... but with digital multimeter doesn't really matter.

the hall sender fault on vag com is normal if the engine is not running... since it has no cam shaft sensor it has no reference for engine speed, so if it's not turning the ecu assumes it's faulty

It's an ADZ , I also presume this test it only valid when its not starting ?

And would a faulty hall sender unit stop the engine from turning over and make clocks dim ect?

[itavaltalainen]

hall sender does not physically stop anything moving, if it doesn't work the ecu thinks engine's not running so won't inject fuel nor fire the coil....

slow cranking and clocks going dim shows that your voltage is dropping.... prob. battery weak due to many attempts but could be that your battery is old or alternator not charging properly... both things that can be checked with multimeter.... guess your battery is down at <12V without engine running. if thats the case it's empty => charge it, see if it holds charge. if it goes to 14V (or there abouts) with engine running and a few things (light, r/w demister) on then alternator is ok. if you got a fairly fast multimeter you prob see how far voltage drops when you try starting.
once had an 11yr old bosch battery that dropped down to 9V when starting.... if it goes anywhere near that it's had it.


if it comes to worst i got a 70A alternator and 2yr old 44Ah varta battery for sale (my gf is forcing me to sell my car spares!)

[spudboy6]

I know the battery if good as I've tested it on a Toyota battery tester and the alternator is giving 14v with lights on ect ,

When I turn the key it half cranks then everything stops , no more cranking and lights dim which does suggest battery , but 15 mins later I turn the key it turns over fine !

[spudboy6]

Maybe a dead starter motor ?

[itavaltalainen]

ah now i understand what you mean....

probably not dead, maybe just full of muck?
try cleaning it, if that doesn't make it better then it's a case for replacement.

[spudboy6]

ah now i understand what you mean....

probably not dead, maybe just full of muck?
try cleaning it, if that doesn't make it better then it's a case for replacement.

It's hard at times to understand what us nutters are on about half the time , ill have a look at it tomorrow , and report back !