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Old 25-11-2019, 07:39 PM   #21
Chat Slapper

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Location: Natnwich
Posts: 154

Thanks Phil,
So the coil had a little fold down door to get at the concealed terminals. Using the 3 pin connector at the top gives a different (and out of spec) reading. Must be some additional circuitry between these terminals and the coil.

So I have ran the tests -

Bridging pos to neg = 0.07 Ohms - In spec (VW state 0.5 to 1.5 Ohms)

Bridging pos to HT Output = 3.08k Ohms - In spec (VW State 2.5 to 4.0 K Ohms)

So the coil is appears good and the ignition leads are reasonably good.

I just need to check the outputs to the coil on the car when its light.

So here's where I am now -

Halls sensor in Dizzy, I believe if these fail then you get no spark, so cant be this?

Knock Sensor, everything I read says this wont stop the car from starting?

ECU Corrupted/problem, timing?

Spark Plugs, all of them failed at once?

Timing jumped, if so why did it run for a period of time after being sprayed with WD

Loose wire, fuse rely, why does it try to start and fire on one or two?
Fuel injection, plugs wet fuel getting in, but when. Fuel pressure, if this was defective wold it register on scanner, and still let fuel trough to cylinders?

Coil defective, and failing under load/spark under compression not enough, thought this was more of a misfire issue under acceleration?

One observation I made yesterday was when cleaning and drying out the plugs, I decided to check the gaps. Looked in the Haynes and it said 1.0 gap. All were tight, so opened up and gapped at 1.0 mm

Put back in the car dry and warm - nothing, not even trying now.

Cross referenced the gap setting on the other sources which recommended 0.9mm which is probably where they were. Now this may be a coincidence but opening the the gap by 0.1mm changed the status from trying to not firing at-all. So could the coil be still suspect as I cannot see a healthy ignition system being bothered by 0.1 mm, but I suppose that its not healthy.

Building a great thread here for the AER 1.0 engine, lets just hope it ends well!

Last edited by Mooresy; 25-11-2019 at 07:43 PM..
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Old 01-12-2019, 05:37 PM   #22
Chat Slapper

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Had another look at this today -
Unfortunately, it started to get dark at about 15.30 so had to pack away without actually trying to start the thing.

Removed ECU, cleaned the connector with electrical cleaning spray.
Opened the ECU and checked for any visible deterioration, water ingress etc. Fine so spayed with electrical cleaner.

Broke all the connections I could find, spayed with electrical cleaner and remade.

Removed the spark plugs again, checked for resistance, continuity, shorting etc, all ok

1 = 4.91k ohms
2 = 4.22k ohms
3 = 4.21k ohms
4 = 4.22k ohms
Should be between 4 and 6.5 depending on resistor so all good and no shorts.

Removed all earth points to engine and body cleaned/sanded and reattached.

Checked the timing by removing all the plugs (already out) removing the Dizzy cap (already off) jacking up one front wheel (other still on the ground), putting in 4th gear and turning the wheel until the screwdriver placed through the spark plug hole had risen to its highest point. Checked the direction of the dizzy rotor and this was bang on the mark on the casing for TDC cylinder No 1.
So no issues with the timing.

So here's the latest list -

New Battery (Varta) all fine here.
New fuel and fuel filter, tank pump working.
New distributor cap, all checked and measured to ensure center pick-up was in contact with rotor (found original to be cracked), also all leads on correct terminals (firing order).
Connection from cap to plug leads checked with multi-meter.
HT Leads all tested with timing strobe, also out of cylinder head with plugs producing a blue spark, and with multi-meter while flexing leads. All fine here.
All pugs checked with multi-meter and correctly gapped at 1.0mm.
Coil checked, LT and HT sides all in spec (also plugs firing).
Timing checked. all good.
No pipes off or split.
All electrical connections taken apart, cleaned with connector cleaning spray.
All engine earth points cleaned and reconnected.
Scan using a Snap-on Solus Ultra - no fault codes now showing.
Throttle body adapted.
ECU removed and checked for water ingress etc(all good), connector blocks cleaned with electrical cleaning spray.

Still wont start, fires and tries.

Further things for consideration -

Dizzy Halls sensor, told if this is bad then you dont get a spark?
Knock sensor. told cant be this?
Lamda/O2 Sensor, can this cause a car not to start?
Crank sensor, can this cause a car not to start?
EGR Valve, can this cause a car not to start?
Corrupted Knackered ECU, Fuel is getting to all cylinders.
All injectors?
Fuel pressure regulator?

Any suggestions on which order to tackle these ?



Last edited by Mooresy; 03-12-2019 at 10:33 PM.. Reason: =
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