https://kb.symtechlabs.com/ 2026-04-29T18:14:20+00:00 https://kb.symtechlabs.com/ https://kb.symtechlabs.com/lib/tpl/arctic/images/favicon.ico text/html 2012-12-10T07:40:38+00:00 https://kb.symtechlabs.com/megasquirt:activate_efi_analytics?rev=1355125238&do=diff Enter the registration code provided to you by SymTech Laboratories to unlock all of the features a paid EFI Analytics software license offers! text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:base_maps?rev=1354259544&do=diff Yes, please see the SymTech Labs MSQ file repository: <http://www.symtechlabs.com/support/msq_rep.php> Return to MegaSquirt Page text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:check_engine?rev=1354259544&do=diff If you install your MegaSquirt system in “parallel” with your stock PCM, a check engine light is unavoidable. If you replace your stock PCM with your MegaSquirt system, you probably won’t physically see the check engine light. In either case, your car will probably not pass an emissions test. MegaSquirt ECU’s are not meant for use on any pollution controlled vehicle. There are strict penalties for tampering with or disabling the stock pollution control devices on cars in the United States an… text/html 2011-01-28T08:18:24+00:00 https://kb.symtechlabs.com/megasquirt:config_support?rev=1296202704&do=diff There a number of great resources for help. Be sure to thoroughly familiarize yourself with the MegaManual and MS1/Extra or MS2/Extra documentation: * MegaManual * MS1/Extra Manual * MS2/Extra Manual For further assistance, consult either the MSefi or MSx/Extra EFI forums: text/html 2011-05-15T17:16:12+00:00 https://kb.symtechlabs.com/megasquirt:downloads?rev=1305479772&do=diff MS1/Extra Firmware * MS1/Extra and MS1/Extra HR Firmware† † MS2/Extra Firmware * MS2/Extra Release Firmware† * MS2/Extra Beta Firmware * MS2/Extra Alpha Firmware † MS3 Firmware * MS3 Release Firmware† * MS3 Release Candidate Firmware * MS3 Beta Firmware * MS3 Alpha Firmware text/html 2012-02-09T00:31:20+00:00 https://kb.symtechlabs.com/megasquirt:flash?rev=1328747480&do=diff Most MegaSquirt users will upgrade their firmware at some point or another. Follow these simple steps to ensure the upgrade process goes smoothly. MS1/Extra Acquiring the Firmware Begin by downloading the latest stable firmware release package. Save it to an easily accessible location on your computer, such as your desktop. The file will be compressed as a ZIP file, so decompress its contents. The resulting folder must be on the same hard-drive as your tuning software. text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:fuel_only?rev=1354259544&do=diff Yes, you can! In fact, we recommend this for users new to MegaSquirt EMS and users new to tuning in general. The MegaSquirt ECU doesn’t need to control spark, idle, or provide power to the sensors for fuel-only control; simply leave the corresponding wires in your wiring harness disconnected. Your MegaSquirt ECU can generally share all of the sensors with your stock PCM, except the IAT and CLT sensors. You may need to install a second set of temperature sensors in order for both ECU’s to coe… text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:fuel_reg?rev=1354259544&do=diff There are two main options, an adjustable 1:1 regulator and a standard static regulator. The 1:1 regulator is the best choice for turbocharged vehicles as it increases the fuel pressure by 1psi for each 1psi of boost pressure. This feature balances manifold and fuel pressure which creates more headroom. You can also alter the base fuel pressure to perfectly dial in your fuel injectors. In other words, “you’ll get more out of your injectors.” text/html 2012-07-26T05:28:05+00:00 https://kb.symtechlabs.com/megasquirt:grounding?rev=1343280485&do=diff Signal noise can be a significant problem while tuning any engine management system. Inaccurate sensor readings due to signal noise are not only a nuisance, but a hazard. The best way to prevent unwanted signal noise is to ground the sensors at the MegaSquirt ECU, and ground the MegaSquirt ECU directly at the engine block. Doing so guarantees the MegaSquirt ECU and sensors are using the same ground reference. text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:how_to_connect?rev=1354259544&do=diff MS1 and MS2 both have serial interfaces. If the computer you will be using for tuning has a serial port, all you will need a straight-through (not null modem) serial cable If the computer does not have a serial port and only has USB ports, you will need a USB-serial adapter text/html 2011-01-28T08:17:18+00:00 https://kb.symtechlabs.com/megasquirt:iac_wiring?rev=1296202638&do=diff Your vehicle's idle air controller (IAC) likely incorporates a stepper motor. This type of IAC requires a special type of driver only available in MS2, MS3, and subsequent systems. The driver is not standard hardware and must be purchased through our MegaSquirt Option Service. text/html 2011-01-28T08:17:44+00:00 https://kb.symtechlabs.com/megasquirt:injector_pairing?rev=1296202664&do=diff Batch Fuel Injection In standard SymTech Labs MS1 or MS2 MegaSquirt ECU's, the fuel injectors are fired using a batch fuel injection scheme. This means the injectors are not fired in any particular order, just the same number of times per unit of time. It does not matter which fuel injectors are connected to which bank of fuel injector drivers using batch injection. Many users opt to group the injectors according to the corresponding cylinder's piston position. For instance, in a four cylin… text/html 2012-12-10T05:34:40+00:00 https://kb.symtechlabs.com/megasquirt:injectors?rev=1355117680&do=diff Enter the required parameters below to calculate the minimum fuel injector size for your application. Aspiration Fuel Pressure† PSIG Desired Horspower HP # of Fuel Injectors‡ Result † ‡ . text/html 2011-01-28T08:18:37+00:00 https://kb.symtechlabs.com/megasquirt:install_support?rev=1296202717&do=diff SymTech Labs can provide support for issues regarding hardware and physical installation. Please contact SymTech Labs for more information. Return to MegaSquirt Page text/html 2011-01-28T08:17:00+00:00 https://kb.symtechlabs.com/megasquirt:jackscrews?rev=1296202620&do=diff This common problem is caused by female jackscrews used on both DB-9 connectors. Simply remove the jackscrews from the DB-9 connector on the MegaSquirt ECU. The connector shells provide enough support to protect and securely maintain the connection without the jackscrews. text/html 2011-01-28T08:16:50+00:00 https://kb.symtechlabs.com/megasquirt:lost_comm1?rev=1296202610&do=diff If you were previously successfully communicating with your MegaSquirt ECU, the firmware is likely corrupted. While extremely poor wiring and severe electrical noise could corrupt the firmware, the more likely culprit is an improperly configured serial connection, or tuning software. Besides ensuring your serial connection is sound, you will have to flash your ECU with the latest available firmware to restore functionality. Be sure the firmware in your ECU matches the .INI file your tuning so… text/html 2011-01-28T08:16:40+00:00 https://kb.symtechlabs.com/megasquirt:lost_comm2?rev=1296202600&do=diff If you were never able to successfully communicate with your MegaSquirt ECU, there are two common causes. First, be absolutely sure your Megasquirt ECU is wired properly. Pay particularly close attention to the +12V and ground connections. You can access our various wiring guides on our main support page: text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:low_z?rev=1354259544&do=diff Yes, it can! There are several techniques for controlling low impedance fuel injectors, each with its own pros and cons. 1. The most basic method for safely controlling low impedance fuel injectors is to add inline resistors to your fuel injectors. These resistors limit the total amount of current through the injectors, but unfortunately the injectors won’t open or close as quickly as they were designed. Sluggish injectors cause sloppy idle control. text/html 2011-03-10T03:59:54+00:00 https://kb.symtechlabs.com/megasquirt:map_select?rev=1299729594&do=diff You should choose the smallest MAP sensor that will suit your current needs and future goals. For all naturally aspirated applications, a 2.5 bar MAP sensor is the best choice. For turbocharged applications, use this guide to help you select an appropriate MAP sensor: text/html 2011-03-10T03:04:31+00:00 https://kb.symtechlabs.com/megasquirt:official_doc?rev=1299726271&do=diff General MegaSquirt Resources MegaManual MegaManual General MegaSquirt information including tuning and v2.2/v3.0 board assembly, etc. A great resource if you're building your own ECU, but not as useful if you're buying a pre-built one. MSefi.com MSefi.com A forum dedicated to MegaSquirt in its standard (B&G) form and running the standard (B&G) firmware. The discussions here are good for very general hardware troubleshooting and tuning advice. text/html 2011-01-28T08:18:09+00:00 https://kb.symtechlabs.com/megasquirt:options?rev=1296202689&do=diff Be sure to review our MegaSquirt Option Service Connection Diagrams document. This guide contains schematics of how each connection should be made. If, after having verified the wiring, the option circuit still does not function correctly, the cause is most likely a firmware setting. text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:other_parts?rev=1354259544&do=diff You will also need a wiring harness, a USB-serial adapter (for MS1 and MS2), and possibly an alternator voltage regulator. Many complete MegaSquirt packages from SymTech Labs already include these things. You will also need a little spare vacuum hose, standard electrical tools (wire cutters/strippers, etc.), solder or crimp connectors, and heat shrink tubing or electrical tape. text/html 2012-05-16T01:06:28+00:00 https://kb.symtechlabs.com/megasquirt:relays?rev=1337130388&do=diff Many vehicles have an auto-shutdown (ASD) relay that provides power to the ignition coil and fuel injectors. For safety purposes, it's best that Megasquirt controls this relay. The same logic that controls the fuel pump relay can be used to control an ASD relay, but unfortunately a Megasquirt ECU's fuel pump relay output cannot sink current from both. Here are a few techniques for connecting both an ASD relay and a fuel pump relay to a Megasquirt ECU's fuel pump relay output. text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:remove_pcm?rev=1354259544&do=diff Yes, you can! This type of installation is usually called a “full installation” or “full stand-alone installation.” In order to complete a full installation, you must order MegaSquirt ECU with the hardware to drive a tachometer, control the radiator fan relays, and fuel pump and auto-shutdown (ASD) relays (if any). For certain applications, such as the 420A/Neon, you must also install an external alternator voltage regulator. text/html 2011-01-28T08:18:51+00:00 https://kb.symtechlabs.com/megasquirt:repair?rev=1296202731&do=diff Absolutely! Please contact our sales staff for pricing and timelines. Return to MegaSquirt Page text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:rev_limit?rev=1354259544&do=diff No, you are not. The stock PCM utilizes a fuel cut type of rev limiter, so giving fuel control to your MegaSquirt ECU effectively disables the stock rev limiter. Return to MegaSquirt Page text/html 2011-01-28T08:16:25+00:00 https://kb.symtechlabs.com/megasquirt:sensors?rev=1296202585&do=diff For the most part, MegaSquirt can utilize all stock sensors. MegaSquirt ECU's with MS-II processors can interface with all stock sensors after a few calibration steps. MegaSquirt ECU's with MS-I processors can theoretically interface with all stock sensors too. In practice, however, the calibration steps for using non-standard IAT/CLT with an MS-I based ECU involve antiquated and difficult to use software. We recommend either using standard GM IAT and CLT sensors for use with all MS-I based … text/html 2011-01-28T08:19:45+00:00 https://kb.symtechlabs.com/megasquirt:serial_connectivity?rev=1296202785&do=diff Here are a few tips and tricks for successfully connecting to your MegaSquirt ECU using your computer's built-in serial port. Please see our article on USB-serial adapter connectivity for information on connecting to your MegaSquirt ECU using a USB-serial adapter. text/html 2012-12-10T07:37:23+00:00 https://kb.symtechlabs.com/megasquirt:start?rev=1355125043&do=diff Articles Mechanical * Fuel Injector Calculator * Chrysler Temperature Sensor Calibration Wiring * Proper Grounding * How to Solder Wires Together * Working with Coaxial Cable * Adding an ASD Relay to the Fuel Pump Relay Output Firmware * MegaSquirt Firmware Downloads * Flashing Firmware into MegaSquirt ECU's text/html 2011-01-28T08:22:36+00:00 https://kb.symtechlabs.com/megasquirt:temp_calib?rev=1296202956&do=diff Use the following information to calibrate your Megasquirt ECU to read your stock temperature sensors. This data is valid for Chrysler temperature sensors used in non-turbo 1995-1999 Mitsubishi Eclipses and non-turbo 1995-1997 Eagle Talons, as well as 1995-2003 Dodge Neons and Avengers with separate IAT and MAP sensors. text/html 2012-07-05T22:40:34+00:00 https://kb.symtechlabs.com/megasquirt:terminology?rev=1341528034&do=diff For all intents and purposes, there are two main components in a MegaSquirt ECU: the main board and the processor. The v2.2, v3.0, and v3.57 boards are the three main boards available. The v3.0 board, as you may have guessed, is newer than the v2.2 board and offers many more standard features. We only recommend the v2.2 board for bare-bones installations; for applications with few technical requirements and a very small budget. The v3.57 board is a surface mount version of the v3.0 board. … text/html 2012-12-10T07:31:59+00:00 https://kb.symtechlabs.com/megasquirt:tuning_links?rev=1355124719&do=diff Tuning Software TunerStudio MS TunerStudio MS TunerStudio MS is the de facto standard for tuning MegaSquirt ECU's. It offers 3D mapping, auto-tuning, custom dashboards and other advanced features. It's written mostly in Java, so it's cross-platform and will work with most operating systems (Windows, Mac, Linux). TunerStudio MS is currently the only tuning software than supports the MS3 processor and newer versions of the MS2/Extra firmware. There is both a paid and free version of TunerStudi… text/html 2012-09-06T01:06:50+00:00 https://kb.symtechlabs.com/megasquirt:usb-serial_adapter_connectivity?rev=1346893610&do=diff Here are a few tips and tricks for successfully connecting to your MegaSquirt ECU using a USB-serial adapter. Please see our article on serial port connectivity for information on connecting to your MegaSquirt ECU using your computer's built-in serial port. text/html 2012-11-30T07:12:24+00:00 https://kb.symtechlabs.com/megasquirt:what_is?rev=1354259544&do=diff MegaSquirt is a powerful engine management system (EMS) that offers full fuel and spark control for many applications, including the 420A/Neon. Its native support for so many applications means it can directly read the stock crank trigger; adding an external trigger wheel or modifying the stock sensors is unnecessary.