Mp9 system not sparking

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Pastu
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Mp9 system not sparking

Post by Pastu »

Hi guys I am really in need of expert advice. I'm running a 2l Mp9 system in my Mk1 1984 caddy bakkie, the car was converted from the standard carb to Mp9 injection. The harness was modified to accommodate the computer box and the electronic petrol pump. The car lost spark and I replaced my coil,module, leads,distributor cap and rotar arm. Took it to some backyard mechanic and the bum swapped out my computer box with what seems to be a 1.4 box. I'm done getting people to work on my car and will be getting a remapped computer box for the 2l. I need advice on what I need to look for that could be causing the no spark at random, should I replace the loom from module to distributor? And another thing sometimes when I try crank the engine my power shuts down completely, where should I look for the short, also once I get the car to on and crank by turning ignition when I turn it off it stays on, then I have to pull out fuse 1 and put it back.
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vandyh
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Re: Mp9 system not sparking

Post by vandyh »

Checked for internal short to ground in the harness (firewall entry)
Make sure you have sufficient earth to the ECU
have you tested the 3-pin coil / hall sender pick-up in the distributor?
Current ride
2007 - Jetta VI 2.0TDI
2007 - Velociti - 2.0 (91wkW, 174nm) @ 8V Performance
2014 - Kia Rio TEC

Previous rides
2008 - Polo 1.9 TDi 14i
2008 - Citi 14i
1996 - Citi Chico
2003 - Ford Fiesta
1986 - Golf MK2
Pastu
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Re: Mp9 system not sparking

Post by Pastu »

Yes I have checked the my coil and hall sender pick up. I will have to check my harness ground as since from the word go I been suspecting a wire issue.

Are there any specific colour wires I should focus on? BROWN and BLACK?
Thank you
Pastu
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Re: Mp9 system not sparking

Post by Pastu »

I replaced the computer box with a 1.8 Polo chipped for 2l, also got the module to coil and distributor loom. I'm gettin spark now but car still won't start, there was a bridged wire from the computer box pin 24 green wire from 24 pin green to green/white distributor wire, should I continue and connect this wire?
Pastu
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Re: Mp9 system not sparking

Post by Pastu »

I replaced the computer box with a 1.8 Polo chipped for 2l, also got the module to coil and distributor loom. I'm gettin spark now but car still won't start, there was a bridged wire from the computer box pin 24 green wire from 24 pin green to green/white distributor wire, should I continue and connect this wire? Wiring diagram states this wire on pin 24 green goes to the ignition control - output trigger coil pin 3, im using the round coil which terminal is this?
Pastu
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Re: Mp9 system not sparking

Post by Pastu »

I replaced the computer box with a 1.8 Polo chipped for 2l, also got the module to coil and distributor loom. I'm gettin spark now but car still won't start, there was a bridged wire from the computer box pin 24 green wire from 24 pin green to green/white distributor wire, should I continue and connect this wire? Wiring diagram states this wire on pin 24 green goes to the ignition control - output trigger coil pin 3, im using the round coil which terminal is this?
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PapaJo
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Re: Mp9 system not sparking

Post by PapaJo »

Let me recap as I read a few things that have been done.

First you lost spark and coil etc was replaced and akso the computer box. Why the computer box and why back yard mechie?? Think you got conned on the computer box.

Secondly, withthe replacement computer box, the wiring seems to have been connected incorrectly and caused all sorts of power issues.

Then you say that there is a wire from pin 24 to pin 24 green wire for ignition signal. Doesn’t seem right to me and is a possible bypass to get car to start as you cannot just plug in another computer box.

That box needs to be decoded to work with your ignition or previous box was probably by passed with that wire to get it to start and run.

I suggest you go back to the backyard mechie and get your own computer box back and then fork out more money and get it repaired by someone more reputable and not backyard.
Pastu
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Re: Mp9 system not sparking

Post by Pastu »

I took my car to the mechanic since i was not having spark, the skelm swapped out my computer box and put a 1.4 ECU, car was having erratic idling, heavy smoke, when i got home I saw that the ground wire from the short loom was burning out, even after replacing it with a thicker wire. Car still had hard starting and cranking would cause the ground wire to burn but once car starts there is no short, this then resulted in me checking my ECU to realise it was swapped, the guy denied doing this obviously, so i purchased a 1,8 that is said to be remapped for 2l.

Pin 24 green wire on the ECU pins was bridged to green/white distributor wire, once I try use this bridge I dont get spark anymore, I replaced the short loom connecting my module,coil and distributor and I am no longer getting a short in my ground. Will i require to get the ECU decoded even when I am using my orirginal mk1 key with no coding?

I am thinking I should get the ECU checked and then after start working from there.

I dont know if it just impossible to sort this out, but this car was driving fine with the mp9 system with the modified carb harness.
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PapaJo
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Re: Mp9 system not sparking

Post by PapaJo »

have the decoded box checked first. You should not have issues to use your original key with the decoded box. The burnt ground wire tells me that some wiring is not where it is suppose to be or is missing, resulting in pulling more current through the wire you have changed to a thicker wire. By changing to a thicker wire will be a temporary solution as the next weakest point in the circuit will burn next now.

What motor do you have installed? The ecu mapping needto match the motor or you will experience the erratic idle, over fueling etc.
Pastu
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Re: Mp9 system not sparking

Post by Pastu »

Thanks for the response, the thicker ground wire solution was before i changed the short loom from module to coil to distributor. I am using 2l MP9 system, got a 1.8 box that must be remapped and decoded.
Dannuall22
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Re: Mp9 system not sparking

Post by Dannuall22 »

I need help with my 2l 8v mp9 ...i converted from digifant ...now everything is installed but if i wire up black and yellow to ignition on theres no spark from coil but if i remove the wire thers spark from coil but throttle body doesnt sing i need help please i checked my coil on my friends car works fine ....and i have a 1.4i open ecu
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