Changing ECU Map while engine running
 

Hi.
Does anyone knows if any damage to the engine results if I change the ignition & fuel mapping of the ECU while the engine is running?

Other thing, does the P28 learn about the driving conditions to improve itself?
If so, always changing between maps will ruin the already learning done on the other map?

Thanks in advance?

Re: Changing ECU Map while engine running
 

if the basecode does not change you may be able to get away with it, but if you add a feature or change any of the basecode it will set a solid CEL and drop to limp mode..

Re: Changing ECU Map while engine running
 

As stated above, possibly. But I wouldn't risk it.

No. It does not learn like current OBD II+ systems of 2011+.

Yes, you will make things worse almost immediately.

Re: Changing ECU Map while engine running
 

You can use the live tuning feature, where it auto-uploads minor changes you make automatically right as you make the changes on the laptop. That is perfectly safe and is standard procedure.
Uploading an entirely new map while the engine is running is typically not suggested

Re: Changing ECU Map while engine running
 

Assuming the OP knows what those changes need to be made

Re: Changing ECU Map while engine running
 

Thanks guys for the replies.
Usually i turn off the engine to change between maps.
The only time i did it with the engine running was at idle and it seemed fine, didn't throw any CEL.
I just wanted to know this because i want to make a map for mountain roads and other for freeway.
Thanks Again.

Re: Changing ECU Map while engine running
 

So what you are saying is
f i have 2 maps, one simple map by Crome the other one by Neptune but with Launch Control and other features i might have issues changing between them?
But if i have, lets say two maps made in Crome with the same features (knock sensor disabled, VTEC Coolant Temp Check disable, etc). With only VTEC Point, Ignition and fueling different it might not pose a problem changing between them with the engine running?

Re: Changing ECU Map while engine running
 

See, ignition and fueling are the big ones to worry about. they aren't an onlything you change. In addition, even NA, you don't need to change maps from a Street use to a mountain/canyon type of fueling unless you're looking at major changes in elevation and fuel consumption (like over 3000 meter elevation changes). Even then, that's something that needs to be done on a full time level.

Shutting the car off isn't really the concern as much, as it is the fact that you're testing higher rpm limits and such with fuel changes/ignition changes you may not be aware of while you're driving the vehicle. I can see different mapping for different fuel types (due to the change in BTUs of energy created by different fuels) but I don't see this as something that's going to really benefit you in the short run. I have this feeling you're going to experience more issues than you'll solve in this process.

Re: Changing ECU Map while engine running
 

Very nice answer.
I want to do a Mountain Map with a lower VTEC point and optimized for higher altitude (1000m). The other map to freeway with a higher vtec point optimized for sea level.
Im also interested in doing a third map with no VTEC, limited to 5000rpm, very conservative ignition and fuel and speed limited. Like a Valet map or something.

Re: Changing ECU Map while engine running
 

you will have a problem with that. Solid CEL for sure. (I tried it)

that depends on how you switch the maps and how big the changes are, and your luck. Personally I'd never depend on this without a software package with the ability to do this. Too much potential for bad issues.

I checked... everything you just described, Neptune has a solution for it. (I'm not trying to sell Neptune, but it does have everything you mentioned)

Re: Changing ECU Map while engine running
 

OK, thanks very much.

Re: Changing ECU Map while engine running
 

If the car is tuned properly, you should never need to change maps. Unless changing fuel types/octanes as mentioned above.

Re: Changing ECU Map while engine running
 

Exactly. And eliminating VTEC engagement completely won't increase any mileage in the lower rpm. That's basically why VTEC was created, because it, in fact, changes the use of the cam profiles from being fuel efficient to having a more aggressive ignition ramp, with the engagement of the 3rd camshaft lobe

Neptune may allow you to change these parameters, but you really need to ask yourself, is it really worth changing? I see this as a no.. Not unless you really know how to actually tune the car.

Re: Changing ECU Map while engine running
 

Very True but what if i want to change the VTEC Point or do a "Valet" Mapping ?

Re: Changing ECU Map while engine running
 

That's was just the idea of having a "Valet" map for other people i borrow the car won't have all the power. The engine would be limited to 5000rpm, so no VTEC.

Re: Changing ECU Map while engine running
 

Again, that would be something to do in the software settings themselves. Not to change an entire Ignition/Fuel Trim Map for. (Although personally, no one would ever valet my car in the 1st place.... Ever. There's no such thing as required valet parking.

Having said that, it's sounding more and more like you need a better software/hardware solution, like Hondata S300 or Neptune. That CROME PRO stuff luckily is becoming the way of the Dodo.

https://cimg3.ibsrv.net/gimg/honda-t...ab3ea930bc.jpg
Dodo bird has been extinct for over 100+ years.

Re: Changing ECU Map while engine running
 

"Valet" is a figure of speech, i might have to lend the car or leave it on a workshop, i don't want people fooling around with it.
For that i'm using a P28 modified with a button that changes between the B16 map on Chip and the D16 map built on the P28. I can change without a problem between the two, but i avoid doing it while the engines running.
Never had problems so far, not even a CEL. BTW, i'm very impressed how well and Smooth the car runs on this map. I don't understand how its possible since the B16 and D16 have different compression ratios.

And its true, Crome is ancient but its free. Neptune and Hondata is expensive. I currently have what i think its a Neptune made chip but i can't open the BIN file on Neptune Free Version. It was a improve from Stock map for sure but i would like to try other maps.
I'm also new to tuning Honda ECUs, i'm more familiarized with Bosch Motronic systems and i'm very impressed how so easy its to Tune Honda's and finding the software to do it.
I'm trying to find all the possibilities for future projects that's why all the silly questions.

Re: Changing ECU Map while engine running
 

I'm not trying to be difficult. But "Valet" infers that you'll be acting as a bailor to someone regarding your property that you cherish. I simply put it as such. If you're willing to trust a shop to keep your car, then you'd better trust it to move the car without the temptation of joy-riding or otherwise abusing your car. That's something that no tech is going to prevent, as a practical matter. All of this is to say that, trust no one, and you won't need to worry about this feature. (Which is also why it's not offered on freeware)

Your questions are not silly at all. But I think you're putting more credit into older OBD1 ECU systems than is actually available. These ECUs are easily to manipulate with the right software interface, but you're thinking Motronic 3.x and 4.x systems from BMW 7 series than what these are capable of. The coding used in Hondas is actually unique, and the days of updating that software on the cheap are long gone. These ECUs don't have Open-Source availabilty that even ECUs past 2007 had. So, you're going to have to start over completely, or use a more robust management system to allow for better CIS Interface and utility.

You're of course free to choose, but those are your options with "free". (Which is also why freeware are for those that are willing to go through the extensive risk.) No one goes out on the cheap to gain features. You want features or flexibility, you must pay for it, unfortunately. Remember, it may seem free, but it really isn't, now, is it? ;) Facts.

Good luck on your endeavor.

Re: Changing ECU Map while engine running
 

Vtec engagement point always has only one single optimal setting in every car. Raising or lowering it will ALWAYS cause a LOSS of power. And the only way to find the ideal engagement point is to do a proper dyno tune. So no, if you actually get it tuned correctly, you do not ever want to change the vtec point.

That's a really good way to grenade your engine. For many reasons; 1) switching between two different memory banks in the ecu while the engine is running (I know you said you avoid this, which is good). But most importantly: 2) using wrong maps blindly with no actual tuning being done. No matter what you "feel", you have no idea how safe or dangerous the maps are for your specific engine setup. This isn't like a foxbody mustang where you can just chip it and drop a chip in and know it'll run well. You NEED to get a professional tune done.

Stop downloading maps. Stop buying pre-programmed chips. Find a reputable tuner and pay to have it professionally tuned.

Re: Changing ECU Map while engine running
 

First of all thanks for all your support.
My problem is i don't live in the USA, i live in a small European Island and no one here can tune Hondas nor do we have access to dynos :cry:
I'm trying to understand the capabilities of this ECU's to see if it's worth it to go further with modifications or future Honda projects.
My current pre-programmed chip was made by these guys for almost stock B16 engines, i know is not custom for my car but the difference from stock map performance wise is awesome and it runs very smooth.
I have no problems so far, no CEL's, the fuel mixture is good.
Everything looks like i might don't have problems in the future but unfortunately that's a risk ill have to take, since the small island i live i can't find no one that have experience on this.
Also its very expensive to take a car to the main land :cry: :cry:
Thanks again for your comments.

Re: Changing ECU Map while engine running
 

Do you have good cell phone reception where you live while driving? Does your phone have a hotspot feature? Do you have a laptop? If yes to all 3, if you get hondata, some tuners can remote tune your car

Re: Changing ECU Map while engine running
 

Being from an island, myself, I can completely understand. But this is more than simple availability. This is about understanding how these ECUs work, and require better management so that you can alter and create changes yourself. this is important especially since you are on an island with fewer resources. That means you get the equipment from the mainland (Buy once, cry once) so that you are self-sufficient in your tuning, or that you have what it takes to supplement an e-tune (as suggested) or be able to make changes based upon some sort of video tutorial.

Your getting the cheapest versions of antiquated hardware/software actually makes things worse.

Re: Changing ECU Map while engine running
 

Agreed. You will pay for an S300 10x in headaches and time spent screwing around with Crome. Do the upgrade and don’t look back. An S300 is not that expensive and should probably be the second or third thing you add to a setup. Meaning, if you’ve got more than a cat back exhaust on the car you’re wasting your time by not having a properly tunable ecu.

Learn to tune. If you don’t have access to dyno on your little island then make friends at an airstrip or something similar and learn to do pulls and overlay data. Dynos are awesome tools but they are far from the only way to tune a car.

Re: Changing ECU Map while engine running
 

Seriously, what?!

I do this all the time while I'm driving the car with zero ill-effects. It should be obvious that ALL changes made to your map should be GRADUAL, and any reshaping should be done while NOT driving the car.

If you are in California (Bay Area) and want some help tuning, I offer the services for street tuning via my business. I'm not cheap, I'm good. Fast and Reliable is all you'll get out of me.