THIS SOFTWARE IS PROVIDED 'AS IS' AND WITHOUT ANY WARRANTY OF ANY KIND, WHETHER ORAL, WRITTEN, EXPRESS, IMPLIED OR STATUTORY, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NONINFRINGEMENT. See the GNU General Public License for more details. FOR OFF-ROAD USE ONLYCredit for most of this updated FAQ and the original code and inspiration for MerpMod goes to Freon, Thanks!
I want to help as many people as possible, and I cannot do this by helping people privately one at a time. So I ask that people do not send me PM's. Rather than seem rude when I ignore you, I ask you first research the subject in this forum, then post in this thread or create a new thread in this forum if you still have questions. You may or may not get an answer. I have limited time with my day job, tuning my car, tuning cars on the weekends, and other hobbies. I'd like to make the most of the time I can set aside sharing with the community.
When posting to get support, provide as much detail as possible. Include any logs, errror messages, and troubleshooting steps you have taken!! We cannot possibly help you without any details!!!Q. What is the scope of this FAQ?
A. This FAQ aims to answer the common questions that new users of MerpMod. It will not cover detailed Speed Density information, which is detailed here:
viewtopic.php?f=37&t=2947 Tuning AFR, timing, and boost will NOT be covered. Furthermore, it is assumed the reader already has a VERY solid grasp of tuning Subarus and tuning in general. There are many other FAQs and information sources for that. This FAQ will cover how MerpMod may affect other aspects of tuning, but it is important the reader already understands these systems independently.
This is not a system to be used by people new to tuning!Q. Who is the intended audience of this modification?
A. Tuners with at least a year of tuning experience Subarus from scratch (stock maps). Those who already solidly have the concept of air to fuel ratio, timing, knock correction, and boost control understood. Tuners should also have experience successfully tuning injector latency, injector flow, and MAF scaling on several cars. These aspects of tuning need to be well understood going in to avoid misinterepretation of what part of the tune is working incorrectly. Since this is a new feature, the most important thing to tuning it correctly will be understanding when the SD part needs to be tuned and when it is another part of the tune that is in need of attention.
This is not a modification for a new tuner to learn. Perhaps as more community is built around, a better information bridge and community support will grow. Perhaps using the MAF will become complete passe for Openecu users. But, for now and at the time of writing this, I will only state this is a modification for those who have MAF calibration problems, big turbos, and those who know well going in how tuning works.
I also strongly suggest that potential readers have read the following books at least twice
through:
How to Tune and Modify Engine Management Systems by Jeff Hartman
Maximum Boost by Corky Bell
Forced Induction Performance by A. Graham Bell
http://dl.dropbox.com/u/27624835/car/ec ... books.htmlThe more experience the user has in tuning MAF scaling tables the better as well, as tuning your VE is a very similar process.
If you meet all of the above requirements, you will probably have success with MerpMod. If you do not, this is throwing another wrench into learning tuning and may lead to incorrect attribution of symptoms. I suggest you stop reading NOW if you do not meet the above experience and research level.
Q. What's the purpose of this modification to the ECU? Why do this?
A. The purpose is to improve the functionality of the ECU and add new functions. The primary
issues are:
1. Limits and issues imposed by a MAF sensor.
2. Adding launch control.
3. Adding flat foot shifting.
Q. Which ROMs are supported by MerpMod?
A. The current list of available Gratis patches is available here:
https://github.com/Merp/MerpMod/tree/ma ... ase/GratisOnly 32-bit SH7055 and SH7058 ROMS are supported. Rom file size will be 512kb or 1024kb.
If your ROM is a compatible 32-bit ROM but is not listed, first check that there isn't another compatible version of your ROM for your car that MerpMod supports. The 'version' is the second to last three digits of the calibration id. e.g. ABCD123E = version 123 of ABCD.E. A list of known roms is available here:
viewtopic.php?f=35&t=7591 If so, copy all of your tables to a new stock rom that is supported, and then apply the patch. Before flashing a new version, always use "Test Write" in ECUFlash first!!
If no compatible ROM is available for your car's ECU, check this forum for a request/bounty thread and reply, or create a new thread with your request/bounty.
Q. How does editing work?
A. Currently, only ECUFlash is supported for editing all MerpMod features.
Q. Where are the explanations and descriptions of each table?
A. In ECUFlash, open the table in question and click "Map Help".
Q. Do I need to re-tune after patching?
A.Yes.
The maps provided are not base maps. Do not expect them to work. You need to provide your own base maps and settings, or at the very least verify they will work on your vehicle.
Q. How does logging work?
A. The standard SSM airflow g/s values are what is calculated by SD. There are new direct-log parameters available in the modified logger XML to log VE and the old MAF scaling table. There is also a new direct-log parameter for raw airflow which is always how much airflow the engine would flow at the current moment IF VE was 100%. It is an intermediate value needed for SD, so I put it in for those who are curious.
Q. How does learning table view work
A. Learning table view is only supported in RomRaider. "Learning View" and other closed source abandonware is not and will not be supported.
The current set of definitions contains everything necessary for learning view and DTC view in RomRaider.
Modified ECU ID to enable support of learning table view is not supported.
Q. How do I create a VE base map?
A. Use the spreadsheet here:
viewforum.php?f=39Q. What happens to the OEM rev limit?
A. The OEM rev limit is no longer used.
Q. I'm having problems with the LC/FFS triggering randomly or not resuming power, how do I stop this?
A. This is caused by pressing the clutch accidentally, or pressing it while not using it a.k.a. 'riding' the clutch. The clutch switch in Subarus is very high in the travel of the pedal. You need to adjust your driving style to accommodate the switch or modify it.
Q. How do I stop the idle from surging?
A. Many users report lowering the Engine load smoothing factors help with idle. You may also investigate some of the experimental idle airflow tables:
viewtopic.php?f=25&t=8688 and hot start enrichment tables:
viewtopic.php?f=25&t=8566&start=75For more information, see the discussion in this thread:
viewtopic.php?f=37&t=9561Q. What do I do if I encounter a problem with the mod?
A. Post in this forum. If you would like a response from myself,
include a log detailing the issue.
Q. Do you plan on making new versions?
A. Possibly. CEL Flashing and flex fuel support are planned for future development.
Q. How much does it cost?
A. It is free to use and distribute, but keep in mind the source code must be included in all distributions of derivative work. If you find the MerpMod patch useful and would like to donate I would certainly appreciate at it, but I cannot offer anything in return for your donation.
https://github.com/Merp/SharpTune/blob/ ... /DONATE.md
or patching in a win 7 VM. I'm also more than happy to perform the patching for anyone who donates.