Fixing damaged wiring caused by EGR leak
 

Hi folks,

I posted on another thread about some issues that have been caused by an EGR bypass that I recently installed (https://the75andztclub.co.uk/forum/s...&postcount=427).

Photo... :(

https://www.the75andztclub.co.uk/for...1&d=1634041158

I have fixed the broken EGR pipe by removing it and fitting a blanking plate on the back of the engine where the EGR pipe was connected.

However, I am now left with a car that only runs in limp mode - the throttle doesn't seem to do anything and it stays at about 1200 rpm. The dashboard shows a 'check engine' light.

The split EGR blew hot exhaust gases onto the side of the engine and as you can see from the photo has melted some of the inlet manifold and wiring to the fuel rail pressure sensor. The manifold damage is cosmetic, but I will swap it for a replacement. To fix the wiring, it's been suggested to me that I replace the engine wiring harness. They're not too expensive on ebay. Has anyone done this before? I was wondering how easy it is.

Another option is to just replace the melted wiring. I assume that when I remove the inlet manifold, there would be a reasonable amount of room to get at the wiring and splice in (with solder) a replacement section of wiring and connector. This means less disturbance to the rest of the wiring harness.

I'd be interested to know what people think about this - is one option preferable over the other do you think?

Cheers,

Al

[QUOTE=al_dente;2903334]Hi folks,

I posted on another thread about some issues that have been caused by an EGR bypass that I recently installed (https://the75andztclub.co.uk/forum/s...&postcount=427).

Photo... :(

https://www.the75andztclub.co.uk/for...1&d=1634041158

I have fixed the broken EGR pipe by removing it and fitting a blanking plate on the back of the engine where the EGR pipe was connected.

However, I am now left with a car that only runs in limp mode - the throttle doesn't seem to do anything and it stays at about 1200 rpm. The dashboard shows a 'check engine' light.

The split EGR blew hot exhaust gases onto the side of the engine and as you can see from the photo has melted some of the inlet manifold and wiring to the fuel rail pressure sensor. The manifold damage is cosmetic, but I will swap it for a replacement. To fix the wiring, it's been suggested to me that I replace the engine wiring harness. They're not too expensive on ebay. Has anyone done this before? I was wondering how easy it is.

Another option is to just replace the melted wiring. I assume that when I remove the inlet manifold, there would be a reasonable amount of room to get at the wiring and splice in (with solder) a replacement section of wiring and connector. This means less disturbance to the rest of the wiring harness.

I'd be interested to know what people think about this - is one option preferable over the other do you think?

Cheers,

Al[/QUOTE

Are the actual wires to the fuel rail pressure sensor in fact cut, burned or in anyway damaged?.
If they are not, as I cannot make it out from the photo, I would leave well alone, you can check the voltage using a multimeter I suppose, if the damage is predominantly to the shield I would use waterproof tape to insulate.

To be honest it is no surprise that the pipe split - nothing is supporting one end, it looks like stainless steel so not too malleable and as it is a stone crusher the vibration will cause a split sooner or later. If anybody else has done something similar the pipe needs supporting at the blanked off end.

Just replace the broken wiring, you dont need to change the whole harness.

I have seen EGR bypasses cause this on more than one occasion, i would stick to a clean original EGR rather than fit a bypass.

Hi Alistair.
I reported on this back on the thread below, and told you that those EGR with out the support are no good at all.
https://the75andztclub.co.uk/forum/s...&postcount=428

You can remove the manifold and you will be able to get to the wiring loom a little more.

https://i.imgur.com/i7I5WsPl.jpg1

To remove the loom is a fair bit of work.
https://i.imgur.com/Fu9PMZzl.jpg2

As Arctic shows replacing the whole loom is quite involved, he also shows, how after a little dismantling, there will be plenty space to effect a repair if needed.


If some or all three wires need replacing just make sure you use the same size of conductor, soldered joints covered with adhesive heat shrink will make a permanent and waterproof repair and finally wrapping the repaired section with tape, including overlapping both ends of the convoluted tubing, self amalgamating tape or similar makes a good waterproof covering.


But, before you do any surgery or dismantling do as has been mentioned and check the out puts and inputs at the plug.

Thanks for the help folks. I'm busy this weekend, but will report back when I've had time to do something.

Hi everyone,

I got hold of a connector to replace the melted wiring, however I went to fit it this evening and I have realised the clip is broken.

The top of the pic is my original connector with melted wiring. The bottom is my 'new' wiring and connector, and you can see the clip is broken.

https://www.the75andztclub.co.uk/for...1&d=1635370073

Has anyone got one that I can buy?

Cheers,
Al

Either solder the good connector on to the new loom or use cable ties.

You should be able to get the wiring out of the plug, try the old one first, then do the new one, once you have the plug off you can add it to your replacement wiring.

I have only just noticed in your original photo at the start of the thread the plug seems to be upside down?