DIY ECU Remapping how hard is it and how to do it

rx7ali

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Not sure if this is the right place to post or not, but here we go.

If i wanted to remap my 2005 Accord 2.2. cdti myself how easy would it be to do?
 
Re: Diesel remaps tech info

you wouldnt be able to. Even if i could i wouldnt want to there are so many parameters.
 
you wouldnt be able to. Even if i could i wouldnt want to there are so many parameters.

If people can learn to diy tune rotarys using a wideband, surely its easy enough to tune a td with the right info and equipment. i have the patience to learn, but need somewhere to start.
 
Not sure if this is the right place to post or not, but here we go.

If i wanted to remap my 2005 Accord 2.2. cdti myself how easy would it be to do?

I don't know what part of the world your from. But I've just got my 08 accord remapped by WG TUNING and the car is totally transformed. BHP over 185 torque over 320nm. Also I can still save fuel if I play gently. By the way WG TUNING are based in Chorley top set up.
 
Re: Diesel remaps tech info

a remap is exactly what im interested in, and yes i know there are a selection of reputable tuners around.

my question however is more towards how do i do conmon rail tuning myself?
 
Re: Diesel remaps tech info

There is an open source ECU remapping project out there where people upload and swap files.

A word of caution though, getting it wrong can literally destroy your engine, the maps are fairly complex 3 dimensional affairs and it is a lot more complex than just hacking in and changing a few numbers around.

Professional remapping companies spend hours of rolling road time optimising their maps before they flash them to customer cars.
 
Re: Diesel remaps tech info

a remap is exactly what im interested in, and yes i know there are a selection of reputable tuners around.

my question however is more towards how do i do conmon rail tuning myself?

You first have to learn what a Diesel engine is about. Many re-mappers are just a bit into IT. This is not what re-mapping is about.

Anyone can alter mapping tables with the right software. Just go to Alientech or Dimsport, which are 2 of a number of suppliers. Ther you can buy the basic hard and software for about 7k and get a training course lasting 2 days.

Unfortunately this is just the beginning.

I don't know where you got the claim from that it is easy to tune rotary engines. It isn't. Bodging is easy, but not proper tuning. Not even a lot of re-mappers get things right. It is as difficult as that!
 
As above +1

The first post isnt totally right you can remap your car but only with the correct equipment

But it is right in the second part - Its not worth it.
The equipment will could cost more than a remap at a specialist.
Also as pointed out you need to know what you are doing. Without a basic knowledge of the point of mapping you would be really lucky to improve it. Learning as you go along is fine as long as you dont care about what you are practising on.

There is no cheap fix for getting more power from engines not ones that work anyway
 
There is an open source ECU remapping project out there where people upload and swap files.

A word of caution though, getting it wrong can literally destroy your engine, the maps are fairly complex 3 dimensional affairs and it is a lot more complex than just hacking in and changing a few numbers around.

Professional remapping companies spend hours of rolling road time optimising their maps before they flash them to customer cars.

Any links to said project sites?

I've moved this to a new thread for you as it will make for a good discussion.

Thanks :)

You first have to learn what a Diesel engine is about. Many re-mappers are just a bit into IT. This is not what re-mapping is about.

Anyone can alter mapping tables with the right software. Just go to Alientech or Dimsport, which are 2 of a number of suppliers. Ther you can buy the basic hard and software for about 7k and get a training course lasting 2 days.

Unfortunately this is just the beginning.

I don't know where you got the claim from that it is easy to tune rotary engines. It isn't. Bodging is easy, but not proper tuning. Not even a lot of re-mappers get things right. It is as difficult as that!

All sounds a bit off putting, but I'm sure there must be cheaper options. Everyone has to start somewhere after all!

Sorry, i didnt mean to imply that rotary tuning is easy. Far from it, rotary tuning is in fact very dificult and errors in map can be DEADLY with event small amounts of DET leading to a dead engine. But people do do it.. and successfully.


My basic thought process would be that a Diesel would be more resiliant to a learner mapper. After all there's no ignition timing to worry about, and (correct me if I'm wrong) but Dettination is alot less of an issue?

I realise that i should probably be exploring alternative avenues to elarn mapping, like a MegaSquirt ECU on a rusty old Turbo Nissan. But i dont have access to one of those, and I'm not in a position to start Mapping my Rotary just yet.

So It'd be nice to see if there are many people out there who are successfully having a crack at modding their Fueling MAP on Turbo Diesels.
 
Here is a link to one of the project sites, http://openecu.org until this really takes off I doubt you'll have much joy but keep us posted as it's something I quite fancy playing around with as I'm quite technically minded and have even written my own printer drivers and monitor info files, plus I hacked a DVD player and got it playing DIVX movies using a flash EPROM chip!

I do think the time and cost will be prohibitive but if it's a hobby and something that interests you then go for it, play away and enjoy.
 
I'd be happy to learn how to do ECU remapping myself, I'm not stupid and I reckon I could learn eventually, I imagine it's not too far away from things like computer programming and system problem-solving which is what I do at work.

I just don't have an endless supply of expensive spare engines to ruin while I learn. So I reckon it's safer to bung an expert a few hundred quid.
 
I'd be happy to learn how to do ECU remapping myself, I'm not stupid and I reckon I could learn eventually, I imagine it's not too far away from things like computer programming and system problem-solving which is what I do at work.

In theory it is as easy as flying. Everyone can do it. The landing is the problem, which in some cases is rather painful to deadly.

For us tuners it is a boring routine to write maps. However in many applications it turns out to be a lot more complex. This might be the case when the tables are limited or sensors need to be changed to different specification or the rpm ceiling being lifted dramatically.

The latter one is a big headache, which many re-mappers don't understand, but can have detrimental effects.
 
I agree with CP lots of things are theortically easy

Its a bit like sword swallowing .........straightforward once you know how but can have disasterous effects if you get it wrong
 
DIY remapping is not for the faint hearted. There have been disasters ranging from unbootable ECUs (dead car) to total engine destruction. I shall be leaving it well alone.
 
I worry when people start hacking their own ECU's. It is fraught with disaters IMO and best left to the people who know what they are doing. If you need to ask about DIY remapping then you shouldn't be doing it. Attend a good mechanical knowledge course and learn the finer points of ECU tweaking.
 
I worry when people start hacking their own ECU's. It is fraught with disaters IMO and best left to the people who know what they are doing. If you need to ask about DIY remapping then you shouldn't be doing it. Attend a good mechanical knowledge course and learn the finer points of ECU tweaking.
I agree, the more I'm learning about remaps and the horror stories I'm hearing of turbos blowing and engines dieing the less inclined I am to fiddle around with remaps.
 
I have just been trolling through some of the comments about DIY ECU mapping with Diesel in mind. Yes it is something that can be picked up from trial and error, more error than trial. YES diesel can and will detonate like a petrol engine and just as quickly self destruct.

The mapping process ideally will be studying 3D maps understanding what they mean and how to read load points. You may not have ignition timing but you have injector timing. Get that wrong and kiss your engine goodby. Too much fuel and you will have a melt down with big holes in pistons.

I have seen many tweeks from "re-mappers" that rely on increasing the fuel pressure to increase power. Not highly recommended. That will increase fuel from idle to full load. Alter injector pulse width were required is the better way to go. The one thing to remember on a standard NA engine you may only pick up a few HP at best. You will gain more from a turbo engine but this will not set the world on fire.

A diesel engine will benefit from the same mods that you would perform on petrol engine ie exhaust, cold air, porting and cams then remap and see the difference. Another thing to be aware of when you have a vehicle dyno tuned, some of the less reputable operators can fudge figures to make it look like they have gained more power than they actually did.

This can be done by altering the inputs to the program like humidity and ambient temps. That will alter the readings. When I ran my own dyno centre I made sure all the information was printed on the sheets so you could compare apples with apples.
 
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I'd still recommend people do a course, there is so much involved in mapping. I've looked into this and there is a lot of potential for causing major problems.
 
To attempt that whole DIY remapping thing, well, the thought would not even enter my head. So many things could go wrong, plus the natural failsafe/warnings that the ECU would normally give you may no longer happen. So expect a bang without the opportunity to prevent it first. I do however admire the OP for even asking the question ;)
 

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