Starting Issue after Replacing Dizzy

[gavL]

So after smashing the Dizzy when trying to get it off finally found a replacement unit, exact same code etc.

Placed it in and the car wouldn't start so done the following:

- The car is a 1990 8v Digifant GTi
- Ensured TDC
- Placed oil pump at correct setting
- Made sure the flywheel was turning when moving the crank by hand
- Checked to ensure a spark was coming through to Cyl1 by unplugging the spark putting it into the HT lead and placing it against the block
- Made sure all HT leads where in the correct place
- Made sure that the Rotor Arm was facing HT1
- Made sure the car was getting fuel
- Checked all earths, cables etc I also checked all the wiring to the Hall Sender but all seems fine

The only thing that changed on the car was the Dizzy and I'm sat here scratching my head at this point. Any input would be appreciated.


Cheers

[warnesey333]

So after smashing the Dizzy when trying to get it off finally found a replacement unit, exact same code etc.

Placed it in and the car wouldn't start so done the following:

- The car is a 1990 8v Digifant GTi
- Ensured TDC
- Placed oil pump at correct setting
- Made sure the flywheel was turning when moving the crank by hand
- Checked to ensure a spark was coming through to Cyl1 by unplugging the spark putting it into the HT lead and placing it against the block
- Made sure all HT leads where in the correct place
- Made sure that the Rotor Arm was facing HT1
- Made sure the car was getting fuel
- Checked all earths, cables etc I also checked all the wiring to the Hall Sender but all seems fine

The only thing that changed on the car was the Dizzy and I'm sat here scratching my head at this point. Any input would be appreciated.


Cheers

The notch on the flywheel in the gearbox cover?

So the car is getting spark, the cylinders are getting fuel

Does it sound like its firing when you try and start it up?

[rubjonny]

does the rev counter jiggle when car is cranking

[gavL]

It does!

I thought that was a sign but kind of looked past it. Hall sender is getting power

[rubjonny]

ok that means ecu is seeing a rev counter signal from the hall sensor, i take it fuel pump primes yes?
i think you need to go back to the timing again, is the rotor arm lined up with the small line on the dizzy when the cam and crank are both at TDC? and you are using the small thin line, not the big notch where the dizzy cap locks into

[gavL]

Yeah it primes fine, took out the Spark Plug from number 1 and it sprayed out after trying to start a couple of times.
Using the big notch for the rotor arm.

Back to basics and reset the timing and everything?

So if I get this right, ensure everything is at TDC again, then ensure that we are using the small thin line?

[rubjonny]

yeah that'll be why, big notch is 180degrees out, you need to use the really small thin line on the dizzy. if you look at the plastic dust shield there should be a tiny notch cut out. It looks like this, pic of a 16v dizzy but you get the idea:

[gavL]

As usual you where exactly right, that was a bit of a learning experience. It starts now and will stay started for a few seconds so going to knock all the belts off again and go through it again and ensure that everything is set to TDC when the rotor arm is set to the line.


Cheers as always mate!

[rubjonny]

I only thought of it because another mate of mine had done exactly the same as you, glad it was an easy fix

[gavL]

Sorry for raising this from the depths.

Still got issues the car starts on first stroke and idles at 1100rpm and engine seems stable, but the rev needle bounces up and down. Had the belts off and on numerous times now thinking its a timing issue.

I keep on coming back to it thinking that its the Hall Sender or Coil? Can anyone shed some light on it?