Help getting my felicia 1.3mpi engine started

[shafty]

Hello, I have a felicia 1.3mpi engine that has been fitted in to a old skoda 100. Unfortunately I'm struggling to get the engine started. 

 

I thought that it might be an immobilizer issue but after a bit of poking about I'm not so sure now...

 

Fuel pump primes when ignition turned on. 

 

The hall sensors (crank sensor) has been mounted to the gearbox and when the engine is rotated by hand I can hear the fuel injectors being activated and the fuel pump kicks back in (these two things are normally blocked by the immobilizer right??) 

 

I don't have any spark at the plugs though :( 

I have 12.54v in to the coil pack on pin 1 and a good earth on pin 4 but I am unsure of how to test any further regarding the ecu controlled connections? 

 

Unfortunately I don't have the diagnostic plug wired in at the moment or any vagcoms stuff yet. 

But I will shortly. 

 

Any help would be greatly appreciated 👍

Cheers 

Rob

 

[Thefeliciahacker]

Immobilizer will let engine run for 2-3 seconds before cutting out.
So if you dont have any spark check that coil receives a pulse

[shafty]

Could you please confirm the correct way to test for a pulse. 

On the coil plug there are 4 pins, pin 1 is a constant 12v and pin 4 is a constant ground. 

I have next to no experience with this kind of ignition (I'm used to points haha) 

Looking at the wiring diagram in the dreaded Haynes manual am I right in thinking pin 3 should be a pulsed 12v from the ecu and pin 2 is a pulsed ground from the ecu? 

[RicardoM]

You need to give us more information on the history of the engine and the car.

Remember you know more than us and we are not wizards.

[shafty]

Unfortunately I can give next to no history of the engine or the car it came from as I got the engine as a unfinished project.

What kind of info would be most useful to you? I'll try my best to answer. 

 

Basically I have the engine... Ecu... Engine loom... fuse box with lots of wires removed as the previous owner has removed as much of the un needed wiring as posable... Immob box... Key... Ignition barrel and key reader... (supposedly a matching set.. But I have no proof of that) 

I have fitted a electric fuel pump wired in as the original would have been. 

I'll put together a proper explanation / diagram of the current wiring when I have a free moment. 

 

But as it stands the only thing that seems to be stopping the engine starting is the fact there is no spark. 

And there appears to be no pulse signal from the ecu... Any advice on things to check to try and determine if the ecu is at fault? 

Cheers

[RicardoM]

8 hours ago, shafty said:

What kind of info would be most useful to you? I'll try my best to answer. 

What is the general setup? Still on the S100 chassis? Or just laying around in a garage?

Let's start with photos/video of the engine from all angles, wiring loom, ecu, immo, ignition transformer, relay box,

8 hours ago, shafty said:

fuse box with lots of wires removed as the previous owner has removed as much of the un needed wiring as posable

That is the scary part which may render (y)our life difficult.

8 hours ago, shafty said:

And there appears to be no pulse signal from the ecu...

Why "appears to be" instead of "it is" or "it isn't" ? You need to tell us how you have checked and what tools/instruments you have used at every step. Remember you have full access to the engine. We don't.

[Thefeliciahacker]

18 hours ago, shafty said:

Could you please confirm the correct way to test for a pulse. 

On the coil plug there are 4 pins, pin 1 is a constant 12v and pin 4 is a constant ground. 

I have next to no experience with this kind of ignition (I'm used to points haha) 

Looking at the wiring diagram in the dreaded Haynes manual am I right in thinking pin 3 should be a pulsed 12v from the ecu and pin 2 is a pulsed ground from the ecu? 

 

I would say check it with a probe light 

[shafty]

I have made up a little 12v led test light now. 

Am I right in thinking I should be running it between pins 2 and 4, and pins 3 and 4? 

Thanks 

[Thefeliciahacker]

5 minutes ago, shafty said:

I have made up a little 12v led test light now. 

Am I right in thinking I should be running it between pins 2 and 4, and pins 3 and 4? 

Thanks 

Between signal pins and ground 

[shafty]

Yep just checking, thanks bud. 

 

I think my first port of call is going to be re wiring the fuse box to how it should be originally as it looks like it's had some rather "interesting" modifications made to it. Then hopefully that will put me in a better position to fult find.

Thanks again 

[shafty]

This is the fuse box as it stands at the moment 

[RicardoM]

Start by checking all grounds (should be all connected if there is no chassis) then all +12V to ECU and sensors. In order to get spark you need the following:

1. correct flywheel for 136M engine
2. good crankshaft position sensor
3. good power and ground to ECU and associated sensors
4. good ignition transformer
5. correct wiring

See schematic diagram below.

 

 

[shafty]

Thanks RickardoM. 

The engine is currently in the car and attached to the chassis.

But I think I will take out the engine loom and fuse box so I can work on it in the evenings at home. 

I tryed to find a pic of the flywheel but I don't have any from a good angle so you can see the cut outs properly. But I have seen on another post a picture of the correct mpi flywheel and it looks the same as mine... It has the extra little slot in it. 

(ill get a picture soon) 

Thanks 

 

[Papez]

On 11/04/2021 at 17:48, shafty said:

. But I have seen on another post a picture of the correct mpi flywheel and it looks the same as mine... It has the extra little slot in it. 

 

Is it mounted correctly to the engine? Its orientation is critical for proper firing order.

[shafty]

40 minutes ago, Papez said:

 

Is it mounted correctly to the engine? Its orientation is critical for proper firing order.

Is it posable to fit it in the wrong orientation? I haven't removed it so I am just assuming it's correct...( You know what they say about assumptions) 

All flywheels I've dealt with in the past have been doweld to fit one way! 

Even if it was wrong I should still be getting spark... Just not at the right time? 

[shafty]

On 11/04/2021 at 15:00, RicardoM said:

Start by checking all grounds (should be all connected if there is no chassis) then all +12V to ECU and sensors. In order to get spark you need the following:

1. correct flywheel for 136M engine
2. good crankshaft position sensor
3. good power and ground to ECU and associated sensors
4. good ignition transformer
5. correct wiring

Well I brought the wiring home the other night and went through it all, removed and replaced all the modifications that had been done so it is all connected as it should be following the diagram. Although I have replaced the ignition barrel switch with a single relay, operated by a toggle switch. 

The starter motor is also operated by a separate push button. 

I fitted everything back in to the car this evening and it is still the same :(

When I turn the ignition on, the fuel pump relay can be heard clicking and the fuel pump runs for probably around 5 seconds or so then the relay clicks off again. The injectors are also receiving 12v in that same period. 

When I turn the engine over the fuel pump relay is activated again and the pump runs and continues to run for a few seconds after I stop cranking.. Then the relay switches off again. 

I don't have any pulse signals from the ecu to the coil or injectors! 

 

Could someone please tell me exactly what effect the Immobiliser has to stop the engine running? Dose it stop the pulse signals like I'm experiencing? 

Also I would really really appreciate it if someone could tell me or share a diagram with me of the Immobiliser and diagnostics wiring. 

 

Thank you in advance for any help given. 

 

[shafty]

The diagnostic plug is currently not wired in.. But I have just got myself the vcds software and cable for my laptop so I would like to wire the obd plug back in. 

Any Info on this (wiring diagram) would be greatly appreciated as I can't see the information I need in the manual I have. 

 

Thanks 

Rob

 

[RicardoM]

Everything works as it should according to your description, except the lack of ignition pulses. Yet I would be careful with the method of testing for pulses. I would not use a test lamp but an oscilloscope. Then I would disconnect the ignition transformer and test again on the connector (in case the ignition transformer is shorted).

 

Read my signature.

 

[shafty]

Thanks RicardoM that's a big help 👍

 

Unfortunately I don't have a oscilloscope or access to one.. Or even how to use one haha (but I'll look in to it) 

 

I did notice when I removed the coilpacks to look at the plugs there was a lot of white powder on the bracket that the coil bolts to. It was obviously coming from the coil as when I gave it a shake I could see the powder falling out??? I'm guessing that's not normal... But I haven't investigated it yet. 

Also is it normal for the w wire in the diagram to have a permanent voltage on it? I was getting about 10.4v on it (if I remember correctly). 

 

I don't know what you mean by "read my signature"?? 

 

Cheers

 

 

 

[KenONeill]

24 minutes ago, shafty said:

what you mean by "read my signature"?

Neither do I, mostly because there is no signature in that post to read.

[RicardoM]

3 hours ago, shafty said:

I don't know what you mean by "read my signature"?? 

Go to your Account Settings, click on Signature, then set to on "View Signature".

[shafty]

I did that... But it was already switched on... Switched it off and on again, saved.. Still nothing? 

What is it that I need to be reading in your signature?

 

[RicardoM]

The forum has a facility similar to a "virtual reputation" mechanism. Instead of saying thank you, useful members get a reputation count each time the LIKE button is pressed. The button lies to the bottom right in every post we make. Since the button is very easy to miss, I added a message to my signature like so:

Click the gray/blue heart (Like) or the magenta cup (Thanks) if you like my post.

I think it is the minimum recognition for the time and passion we put in helping other members.

[shafty]

Ahh I see. 

Well call me old fashioned but I still like to say thank you... But I'll also click your little thumbs up button.. I guess points mean prizes and all that haha 

 

[RicardoM]

6 minutes ago, shafty said:

I guess points mean prizes and all that haha 

Sure, a free 4 weeks holiday to Bali. All included.