Coding a Renault 1.5 DCi Delphi Injector

Coding a Renault 1.5 DCi Delphi Injector

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anonymous-user

Original Poster:

59 months

Monday 28th February 2022
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I have a 2007 Renault Megane with the 1.5 DCi 86 engine which runs Delphi fuel injection. For a while now there has been a big puff of smoke on start up and slightly rough running for about 30 seconds.

I have done a leak off test and it has highlighted that injector 4 (furthest right facing the engine) has an issue and is returning way more diesel than the other three. Having searched the internet it would appear the high pressure fuel pump on these is prone to bearing failure at 100K miles (mine has 101K on the clock) and causes particles of metal to get into the fuel system and damage the injectors.

However, the car starts on the button and runs fine when warm, it is just the smoke and rough running on startup. I can get a refurbished injector for £80 and I think it is worth the gamble as the rest of the car is perfect and I have had no issues in nearly five years of owning it. If the fuel pump is failing it is scrap anyway, so I am happy to spend £80 on the chance it is just a failing injector and not the fuel pump.

However, these injectors have a 16 digit code and need to be coded to the car, something I don't have the equipment to do. Some people have said they have replaced them without coding and the car runs fine, I am just wondering if anybody has tried this and has any experience. I am quite happy to buy something to code them if need be, but I am loathed to buy some cloned CLIP hardware from china in case it doesn't work.

Any advice would be gratefully received.


daydotz

1,751 posts

166 months

Tuesday 1st March 2022
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Funny enough we have just had to replace all 4 injectors on our 07 clio dci 86 because the fuel pump done exactly that i believe ours had to be coded to the car

You haven't said but I'm hoping you have replaced the fuel pump

Edited by daydotz on Tuesday 1st March 16:56

anonymous-user

Original Poster:

59 months

Wednesday 2nd March 2022
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Currently I only have one that is dodgy so for the sake of an £80 injector I thought I would give it a go and replace just that one. If the fuel pump is failing then the car is going to be weighed in.

daydotz

1,751 posts

166 months

Friday 4th March 2022
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Joey Deacon said:
Currently I only have one that is dodgy so for the sake of an £80 injector I thought I would give it a go and replace just that one. If the fuel pump is failing then the car is going to be weighed in.
You sound like you have the skills to keep it running on a shoes string you have vested £80 surely a fuel pump is a better solution & keep it running

anonymous-user

Original Poster:

59 months

Friday 4th March 2022
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daydotz said:
You sound like you have the skills to keep it running on a shoes string you have vested £80 surely a fuel pump is a better solution & keep it running
It's not just the high pressure fuel pump, if that has failed it also needs four injectors, all of the fuel lines cleaned/replaced, new fuel filter and the tank drained and cleaned. I believe back in the day when these cars were worth something, a main dealer would have quoted about £4K.

I am happy to gamble the £80, the injector arrived a couple of days ago and I will fit it tomorrow. If it does eventually turn out it is the fuel pump bearings failing then it will be weighed in and I will probably look for a Scenic or Megane with the 106 BHP version as this has Siemens fuel injection which doesn't suffer from this issue.

Although I am also tempted to replace it with a Kia Rio with the diesel engine if it dies.





bearman68

4,753 posts

137 months

Friday 4th March 2022
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Hello Joey.
As you know, I run lots of these sheds.

Here's what I would do.

1) Take the inspection cover off the top of the diesel tank, and drop a magnet on a stick into the tank - if it comes out covered in metal filings, don't bother, and go and look for scrap quotes.
2) If this is OK, I have in the past removed the suction control valve on the fuel pump, and put the same magnet into the recess. Metal filings, and it's goodnight from him.
3) If these are OK, by all means change the injector. Just change it, and don't bother coding it. Think of coding as a start place for smooth running - each injector injects just a very small amount different from the injector next door. It calculates this off the crank position sensor (very clever). A coding is just a starting position, so without the coding, it will take longer to get to the optimum for smooth running, but it will eventually get there.
4) If it's blowing smoke on start up, I wouldn't bother with the injectors, and I would change the glow plugs instead - this is the usual problem. It must be developing fuel rail pressure and therefore injecting, otherwise you wouldn't be getting white smoke (unburnt diesel, because it's cold).

Oh, and just for reference, it's French so the injector next to the gearbox, is injector 1 (not 4). rofl

Hope that's a little help.

anonymous-user

Original Poster:

59 months

Friday 4th March 2022
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Hello Bearman,

I think we are pretty much the only two people who love these French sheds with the 1.5 Dci engine. I changed all four glow plugs a year or so ago, I was amazed to find that three of them had actually failed once I had taken them out and tested them with a car battery.

It has been producing smoke on start up for years, but recently it has got to the stage where it is a little embarrassing starting it with my neighbours around. As I said I did a leak off test recently and the bottle for injector 4 (or 1!) filled much quicker than the rest which were all pretty equal and slow filling.

I ordered a reconditioned injector from eBay for £80 and this arrived this week so I am just going to fit it tomorrow and see where we go from there.

My main concern was whether the injector needed to be coded or not, but you have confirmed what I hoped and that it will run just fine but may be a couple of percent off optimal which I can live with.

If it makes little difference then I will just continue to drive it until it gives up the ghost and weigh it in.