No spark issue

[Aasan 10]

Hi, 

I have a 93 corrado vr6. Currently the car is a non starter, the car cranks and is getting fuel just no spark. I am receiving a signal at the distributor (main lead) but it doesn't go anywhere past that. The the 3 wire plug attached to the dizzy is not giving me any reading. Looking at google I'm lead to believe that this goes direct to the ecu and I require a new ecu. Does anyone have any idea of what I can do apart from getting a new ecu? 

[vw rule 19]

Hello there,

as your VR6 has a distributor it won't have a crank sensor, so the ECU needs a signal to tell it that the engine is rotating, plus confirmation of ignition spark which it gets partly from the Hall sensor I think, which is inside distributor it's what the 3 pin plug is connected to on the side of dizzy, plus it's semi connected to the ignition coil. If the Hall sensor has burnt out then the engine possibly may not start up, as no signal to ECU. If the ignition coil has gone then engine definitely won't start up.

According to the Corrado Bentley manual, it says with ignition switched off remove the 3 pin connector plug from distributor, using a multimeter set at 20volts connect the leads to the outer terminals i.e (pin 1 and pin 3) switch ignition on you should see a minimum reading of 4.5volts or higher, if no voltage then could be wiring fault or a fuse blown or a problem with ECU ?

Hall sensor terminals: (has 3 pins)         Pin 1 =  Earth (-)  brown/black wire goes to terminal/pin 33 of the main 42 terminal/pin round engine harness plug.     

 Pin 2 =  Signal/pulse wire to ECU goes to terminal/pin 21 of the main 42 terminal/pin round engine harness plug, then from main round harness plug goes to terminal 44 of ECU  white/red wire 

 Pin 3 = Power (+) black/yellow wire

***********************************

The other thing to check is your ignition coil, if that has died then your Corrado 100% won't start up. Looks like the coil has a 3 pin connector plug, and is partly connected to ECU.

Pin 1 = Earth (-) brown wire this goes to terminal 6 of the 42 terminal round main engine harness plug, 

Pin 2 = signal/pulse wire black/red wire goes to terminal 8 of ECU

Pin 3 = power (+) black wire only powered when ignition is on or cranking engine over. Also is partly connected to terminal 38 of ECU

You should have battery voltage between pins 1 & 3 of the 3 pin connector plug for coil with ignition switched on.  (Multimeter set at 20 volts)                                                        Also on the coil there should be two contacts marked as (1) and (15)              (1) and (15) = Primary.                            (15) and king lead round socket (4) = Secondary.       

Measuring between (1) and (15) you should have primary residence of 0.5 to 0.7 ohms.

Measuring between (15) and king lead socket (4) you should have secondary resistance of 3000 to 4000 ohms.

The Bentley manual says if above readings are not within range or not obtained, to disconnect the battery earth lead, and remove coil and repeat test.

Regarding the coil you should have continuity between the terminals something like 7 to 8 ohms, or your multimeter should bleep to confirm you have continuity.                                   Also I think you can possibly check the signal/pulse operation is working, by measuring between pin 1 (-) and pin 2 (pulse) you should see pulses on your multimeter in volts, or I think you can use an LED pulse tester to check operation.

 

hope this helps

si

Edited February 28, 2020 by vw rule

[fendervg 29]

Good advice there on fault finding - but the dizzy VR does have a crank sensor - I know because I've replaced mine twice! The crank sensor is what tells the ECU that the engine is turning, and switches the fuel pump relay on, and maybe ignition too. But if you get fuel, that part is working. 

Have you checked/replaced the cap and rotor arm? The Hall sender is part of the dizzy and can't be bought separately as a repair kit unlike on some other cars, so you'd need to replace the whole thing unfortunately.

[vw rule 19]

2 hours ago, fendervg said:

Good advice there on fault finding - but the dizzy VR does have a crank sensor - I know because I've replaced mine twice! The crank sensor is what tells the ECU that the engine is turning, and switches the fuel pump relay on, and maybe ignition too. But if you get fuel, that part is working. 

Have you checked/replaced the cap and rotor arm? The Hall sender is part of the dizzy and can't be bought separately as a repair kit unlike on some other cars, so you'd need to replace the whole thing unfortunately.

Oh ok mate I presumed the later type VR6 with the full coil pack only has the crank sensor, I didn't think the early type with distributor had one.

Si 👍

[fendervg 29]

I think the coil pack had separate can position sensor instead of the hall sender on the dizzy version. Both had the CPS on the bottom front of the block.

Edited February 28, 2020 by fendervg

[Aasan 10]

Hi guys,

Thank you for your replies, I will test the multi plug as u suggested.

As for the ignition coil its brand new, I think this is the place where another 3 plug is connected but only one HT lead comes out of?

I have replaced the rotor arm and cap but not the whole dizzy.

If I pull the distributor will this give me any indication if it is okay or not? Or just change it?

 

[vw rule 19]

As Fendervg has mentioned regarding the crank sensor, if this sensor fails it can result in no spark. The crank sensor I think as Fendervg has said is attached to engine block, it's on the front side behind or under the oil filter area, think it pulsates off the toothed ring which is moulded/made to crankshaft, close to flywheel end of crank.

Regarding the distributor the safest way to remove it is to set your engine to TDC, once engine is timed up the rotor arm should be pointing to number 1 HT lead on dizzy cap, plus ideally rotor arm to be inline with the small notch cut out mark on the top side edge of distributor. Also you can use tipex or small chisel to make an in-line mark where the dizzy sits against cylinder head, just so you know then what position your dizzy was in (mark the dizzy and cylinder head where they both meet)

Yes your coil should have the one HT lead coming from it (The King Lead) which goes to centre terminal socket of dizzy cap.

So just to clarify you don't have any spark at all from your coil ?                        

 

Si 

[fendervg 29]

From memory, the VR6 distributor will only fit in one positions, so it's easy to remove and replace - I've certainly had mine off a few times and never needed to do marking or positioning. It might be different on the 1.8/2.0 cars.

[Aasan 10]

14 hours ago, vw rule said:

As Fendervg has mentioned regarding the crank sensor, if this sensor fails it can result in no spark. The crank sensor I think as Fendervg has said is attached to engine block, it's on the front side behind or under the oil filter area, think it pulsates off the toothed ring which is moulded/made to crankshaft, close to flywheel end of crank.

Regarding the distributor the safest way to remove it is to set your engine to TDC, once engine is timed up the rotor arm should be pointing to number 1 HT lead on dizzy cap, plus ideally rotor arm to be inline with the small notch cut out mark on the top side edge of distributor. Also you can use tipex or small chisel to make an in-line mark where the dizzy sits against cylinder head, just so you know then what position your dizzy was in (mark the dizzy and cylinder head where they both meet)

Yes your coil should have the one HT lead coming from it (The King Lead) which goes to centre terminal socket of dizzy cap.

So just to clarify you don't have any spark at all from your coil ?                        

 

Si 

Thank you for all the information, I'm only 21 so I've never really dealt with distributors and stuff. It is much appreciated. This is all on the list of things to check on the weekend.

The main coil has power, so the king lead is good, but doesn't go past this. The 3 pin plug attached to the coil has power, but the one on the dizzy is all negative.

I have replaced the main coil, bcm, HT leads, tried a different fuse box also. 

I am thinking of pulling the ecu apart, rigging a test bench and checking the resistors and such using a multimeter. But want to rule out all other issues first.

[Dox 22]

Did you buy the car as a non runner?

 

A faulty crank pos sensor will give no spark or fuel.

Do you have fuel at the rail?

Are the spark plugs wet with fuel after cranking and removing them quickly afterwards

[Aasan 10]

Hi guys,

Good news my corrado is finally running turns out I had to replace the ECU, distributor, fuel pump and also the main ECU relay was missing.

I was wondering if anyone would be able to tell me where connector d/6 from the fusebox goes to, I think according to the Bentley manual the wire goes back into the fusebox but if I plug it back where I found it, the car will stay running even with the key out.

Any help in this matter would be greatly appreciated.

[fla 9]

Impressive that at your age you're getting stuck into identifying and sorting problems on the car - well done!  

[Aasan 10]

2 hours ago, fla said:

Impressive that at your age you're getting stuck into identifying and sorting problems on the car - well done!  

I think it's more making a mess and then fixing it, but i'll get there.

[vw rule 19]

18 hours ago, Aasan said:

Hi guys,

Good news my corrado is finally running turns out I had to replace the ECU, distributor, fuel pump and also the main ECU relay was missing.

I was wondering if anyone would be able to tell me where connector d/6 from the fusebox goes to, I think according to the Bentley manual the wire goes back into the fusebox but if I plug it back where I found it, the car will stay running even with the key out.

Any help in this matter would be greatly appreciated.

Hello there,

according to the Bentley manual the ECU power supply relay (109) has 6 pin contacts.

Pin 1 = earth 

Pin 2 = possibly on same circuit track as tachometer, looks like it's linked to D/6 which is linked also to G1/12 ECU tacho signal, green/black 0.5mm wire to terminal pin 22 in ECU. But on some VAG vehicles D/6 is left blank I think.

Pin 3 = ignition power to energize relay once turned to on position or when cranking engine.

Pin 4 = permanent live 12v from battery.

Pin 5 = is linked to G1/7 black/brown 0.5mm wire to terminal pin 9 in ECU.

Pin 6 = power output to ECU linked to G1/10 red/blue 2.5mm wire which goes to (E7 = welded wiring harness point / multipoint fuel injection wiring harness loom), wire changes from 2.5mm red/blue wire to 1.5mm red/blue wire to terminal pin 23 in ECU. Also partly linked to the N80 Evaporative emission frequency valve (purge valve)

 

G1-12 pin white plug = engine compartment wiring harness. In back of fuse box on lower row roughly mid way, look at image attached below.

D-12 pin green plug = Optional equipment wiring harness. In back of fuse box on lower row 5th from left. Look at image attached below.

 

Hope this helps

Si 

[Aasan 10]

5 hours ago, vw rule said:

Hello there,

according to the Bentley manual the ECU power supply relay (109) has 6 pin contacts.

Pin 1 = earth 

Pin 2 = possibly on same circuit track as tachometer, looks like it's linked to D/6 which is linked also to G1/12 ECU tacho signal, green/black 0.5mm wire to terminal pin 22 in ECU. But on some VAG vehicles D/6 is left blank I think.

Pin 3 = ignition power to energize relay once turned to on position or when cranking engine.

Pin 4 = permanent live 12v from battery.

Pin 5 = is linked to G1/7 black/brown 0.5mm wire to terminal pin 9 in ECU.

Pin 6 = power output to ECU linked to G1/10 red/blue 2.5mm wire which goes to (E7 = welded wiring harness point / multipoint fuel injection wiring harness loom), wire changes from 2.5mm red/blue wire to 1.5mm red/blue wire to terminal pin 23 in ECU. Also partly linked to the N80 Evaporative emission frequency valve (purge valve)

 

G1-12 pin white plug = engine compartment wiring harness. In back of fuse box on lower row roughly mid way, look at image attached below.

D-12 pin green plug = Optional equipment wiring harness. In back of fuse box on lower row 5th from left. Look at image attached below.

 

Hope this helps

Si 

Hi Si,

Thanks for your help once again, I think I worded my question wrong as there is a single black connector that comes off of pin d6 on the fusebox. If u look in the picture you can see the red connector block at the end of the fusebox the black wire going into there it is a single connector. I will have a look and see if I can connect it to g1/12. 

But there are a few unidentified wires so I may put the car back together and see what doesn't work and then go from there.

for an old car there sure are a lot of wires.

[vw rule 19]

6 hours ago, Aasan said:

Hi Si,

Thanks for your help once again, I think I worded my question wrong as there is a single black connector that comes off of pin d6 on the fusebox. If u look in the picture you can see the red connector block at the end of the fusebox the black wire going into there it is a single connector. I will have a look and see if I can connect it to g1/12. 

But there are a few unidentified wires so I may put the car back together and see what doesn't work and then go from there.

for an old car there sure are a lot of wires.

No don't connect that single black wire to G1/12 as that is possibly for the tachometer, and might blow/damage something. If that black wire is keeping the engine running where it was connected to before, then something is wrong.

Just to clarify this black wire you say it's connected to the red connector block at the end of fusebox, is it the one I've marked with white dots in your photo ??

Si 

 

[Aasan 10]

10 hours ago, vw rule said:

No don't connect that single black wire to G1/12 as that is possibly for the tachometer, and might blow/damage something. If that black wire is keeping the engine running where it was connected to before, then something is wrong.

Just to clarify this black wire you say it's connected to the red connector block at the end of fusebox, is it the one I've marked with white dots in your photo ??

Si 

 

Yes that is the correct cable, it is a constant live and the other connector in that block is used for the fuel pump. 

[vw rule 19]

Ok so this is how the fusebox looks without the red connector block adapter fitted.

Purple dot = is terminal spade Z1 (possibly not used on VR6) = but on some 8v or 4 cyl VAG vehicles it is linked to fuel pump/relay and fuse 18, and possibly power feed to fuel injectors ?

Red dot = is terminal spade 30B = permanent power live to fuel relay (167) but this relay won't activate/energize until ignition is switched on.

Yellow dot = is terminal spade 30 = this is the permanent live from car battery, which should be connected to 30B to give live 12v to fuel relay. Think it's a red 4mm wire might have a connection point mid way along wire which then transfers battery live to 30B pin. Or some vehicles I think may have a fusiable link where the wire is joined, either covered with black insolation tape, or connection point plug, or soldered with heat shrink tube covering.

Looks like the red connector block adapter is fitted over terminal spade pins 30B and 30, to allow more smaller wire's to be fitted, but not all VAG vehicles used this adapter block.

Si 

Edited November 28, 2020 by vw rule

[vw rule 19]

According to the wiring diagrams in the Bentley manual 1992 to 1993 Corrado with distributor fitted, the fuel relay should be as below.

Z1 = red/yellow wire (can be linked to fuse 18 on some VAG models for fuel pump relay, and or fuel injectors.

30B = 4mm red wire this is the permanent live power to fuel relay (167) but relay won't activate/energize until ignition is switched on.

30 = 4mm red wire is a permanent live from the battery (this is the main power live from battery for fuse box) which then goes to pin terminal 30B in fuse box. Terminal spade pins 30B and 30 are both linked according to the Bentley manual wiring diagram.

Fuel relay (167) this has 9 pin contacts.

Pin 1 = possibly not used but is used on some 8v and 16v and G60 up to about 1992 / early 1993 MK2 Golf / Jetta / Corrado. But this is on the 50 circuit which only receives power once ignition is in the start position, according to the Bentley manual.

Pin 2 = power live from ignition switch will energize relay when ignition is in on position or cranking engine.

Pin 3 = output power to ECU from terminal pin G1/3 (G1 is the white 12 pin plug in back of fuse box) yellow/blue 0.5mm wire goes to terminal pin 6 of ECU. 

Pin 4 = goes to fuse 18 (20 amp) also partially be connected to Lambda sensor control module via G1/8 red/yellow 1mm wire. (G1 is a 12 pin white plug in back of fuse box)

Pin 5 = goes to G1/6 possibly not used (G1 white plug pin 6 of this 12 pin plug)

Pin 6 = this is connected to terminal single spade pin 30B in fuse box = 4mm red wire goes to terminal pin 30 in fuse box (permanent live)

Pin 7 = goes to terminal pin G2/7 of white 12 pin plug and terminal pin T/2 (T is 2 pin green plug) in fuse box,  possibly not used blank.

Pin 8 = blank possibly not used, but on some VAG vehicles can be an earth.

Pin 9 = goes to terminal pin M/4 of black 6 pin plug, and terminal pin G2/5 of white 12 pin plug, and U1/8 of 14 pin blue plug. Possibly not used blank.

hope this helps

Si
 

Edited November 28, 2020 by vw rule

[Aasan 10]

10 hours ago, vw rule said:

According to the wiring diagrams in the Bentley manual 1992 to 1993 Corrado with distributor fitted, the fuel relay should be as below.

Z1 = red/yellow wire (can be linked to fuse 18 on some VAG models for fuel pump relay, and or fuel injectors.

30B = 4mm red wire this is the permanent live power to fuel relay (167) but relay won't activate/energize until ignition is switched on.

30 = 4mm red wire is a permanent live from the battery (this is the main power live from battery for fuse box) which then goes to pin terminal 30B in fuse box. Terminal spade pins 30B and 30 are both linked according to the Bentley manual wiring diagram.

Fuel relay (167) this has 9 pin contacts.

Pin 1 = possibly not used but is used on some 8v and 16v and G60 up to about 1992 / early 1993 MK2 Golf / Jetta / Corrado. But this is on the 50 circuit which only receives power once ignition is in the start position, according to the Bentley manual.

Pin 2 = power live from ignition switch will energize relay when ignition is in on position or cranking engine.

Pin 3 = output power to ECU from terminal pin G1/3 (G1 is the white 12 pin plug in back of fuse box) yellow/blue 0.5mm wire goes to terminal pin 6 of ECU. 

Pin 4 = goes to fuse 18 (20 amp) also partially be connected to Lambda sensor control module via G1/8 red/yellow 1mm wire. (G1 is a 12 pin white plug in back of fuse box)

Pin 5 = goes to G1/6 possibly not used (G1 white plug pin 6 of this 12 pin plug)

Pin 6 = this is connected to terminal single spade pin 30B in fuse box = 4mm red wire goes to terminal pin 30 in fuse box (permanent live)

Pin 7 = goes to terminal pin G2/7 of white 12 pin plug and terminal pin T/2 (T is 2 pin green plug) in fuse box,  possibly not used blank.

Pin 8 = blank possibly not used, but on some VAG vehicles can be an earth.

Pin 9 = goes to terminal pin M/4 of black 6 pin plug, and terminal pin G2/5 of white 12 pin plug, and U1/8 of 14 pin blue plug. Possibly not used blank.

hope this helps

Si
 

I appreciate all your help, you're like a corrado Wizard. I managed to get most things working today and got the dashboard in as well.

Next on the list is trying to fix the door mirrors as they don't work lol. Back to the wiring diagrams again.

Thank you once again sir.

[vw rule 19]

2 hours ago, Aasan said:

I appreciate all your help, you're like a corrado Wizard. I managed to get most things working today and got the dashboard in as well.

Next on the list is trying to fix the door mirrors as they don't work lol. Back to the wiring diagrams again.

Thank you once again sir.

No worries glad to be of help 👍

You're only 21 and sorting out electrical issues fair play you're doing a great job there 👏

Si 

[1xshaunx1 27]

The mirrors should be easy after all that. It’s usually the contacts in the switch that get covered in green corrosion and need cleaning off. 

[g0ldf1ng3r 13]

1 hour ago, 1xshaunx1 said:

The mirrors should be easy after all that. It’s usually the contacts in the switch that get covered in green corrosion and need cleaning off. 

if it is an early model there is a "how to" in the wiki for cleaning the wing mirror switch - i did mine a couple of weeks ago on the 16v & it brought the drivers side back to life but not the passenger sadly

the dog bone things float on the springs by the way & are tiny so some tweezers help to put them back in place 

[Aasan 10]

1 hour ago, g0ldf1ng3r said:

if it is an early model there is a "how to" in the wiki for cleaning the wing mirror switch - i did mine a couple of weeks ago on the 16v & it brought the drivers side back to life but not the passenger sadly

the dog bone things float on the springs by the way & are tiny so some tweezers help to put them back in place 

 

2 hours ago, 1xshaunx1 said:

The mirrors should be easy after all that. It’s usually the contacts in the switch that get covered in green corrosion and need cleaning off. 

Thanks guys, gonna get some brasso and vaseline and have a go tomorrow

[Aasan 10]

Also what oil do you guys run in your vr6? Currently there is Mobil 1 inside the car but not having ran for 2 years and constantly being turned over I suspect it's more petrol than oil.

I would use Mobil 1 again but they no longer make a 10-30/40, after some research on the forums I think Castrol semi synthetic would be good for the engine. 

Also I'm thinking of running BKR5EKUP plugs, any different recommendation?