EFI guys, any options for theft protection?

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DionR

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Due to recent developments on the site here with homebrewed traction control (@racerjoe @Map63Vette), I have been overviewing different aftermarket EFI systems just out of curiosity.

One thing I ran across was the option in one of the Holley systems to password protect your tune. This got me to wondering if there are any options to turn fuel on or off based on a pulsed signal?

I know, it's kind of a jump; traction control -> locked tunes -> theft protection. But that's how my mind works sometimes.

Seems like a reach, but just wonder if there is a way to trigger the ECU so it knows the car is "unlocked" and a start command is followed or if an un-authorized start attempt would result in either no spark or no fuel. Pretty much an OEM setup except in an ECU you have access to and control. Hopefully a password setup would protect that as well.

I'm a little finicky about this stuff. Had a friend who's car was stolen out of his garage so it's something that is on my mind. Nothing is perfect, even the new cars are stolen, but just seems like something to add difficulty. Just maybe give the opportunity to find the twit sitting in the drivers seat wondering why it won't run so he can "trip" a couple of times before the police show up. :)

Found one thread where the guy asked about a tune that wouldn't run (no fuel or spark) and then loaded with a handheld. Rather something that could be turned on and off at the push of a button. I've heard of dual tunes, does MSPro or a Terminator X allow for that?
 
And yes, I know a tow truck trumps all that. Funny thing is, I hardly ever see car thieves start with a tow truck when they steal Scat Packs and Hellcats. Might drive it around the corner to one, but usually the video's are of how fast they start and drive them away.

So, I kind of think most of these guys aren't' running around with a tow truck.

Heck, seems like half the time anymore, they just wait until you come back and then jack the car and drive over you while you are laying on the ground bleeding from a head wound.

There is no perfect fix.

I just wondered for the sake of discussion. Well, and because someday I want to road trip my car and it would be nice not to have it disappear from a hotel parking lot 1000 miles from home.
 
It’s an electric fuel pump. Pull the fuel pump fuse.
 
First, a short answer to your question. Yes, I'm sure it can be done. Big issue is (apparently) how sensitive the electronics within the system are. They don't like to be meddled with. At least on the ignition side of things. The fuel side is the easier side.

Now when I first started this stuff. If a guy could have made my junk even run well enough for him to steal it. I'd have said good riddance. (OK not really)

But if you could find a way to replicate even a small portion of all the ignition side RF/EMP garbage I dealt with and could eliminate it when you wanted. Then you got something.

I highly doubt that Holleys program is an open source code program so fuddling with it is more than likely out of the question. You could trick it and load a bad program. But what a pain in the ***.
 
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On my AEM ecu I can load and unload a complete tune file. Same with megasquirt. If you load a blank tune the engine will never run. But seriously just unplug the fuel pump fuse.
 
Wasn’t really looking for ideas as much as I was curious if the aftermarket had any options. There are certainly multiple ways like pull a fuse, hidden battery disconnect, etc.

I guess I was thinking of the way the OEM JTEC works with the module in a Ram or Jeep GC where they communicate over a 2 wire network. If the module doesn’t get the unlock signal, it tells the PCM not to run and the truck shuts off after a second or two. Wondered if any of the aftermarket EFI systems could do something similar.

If multiple tunes can be loaded and switched on the fly, I could see something like this working. Just don’t have the experience or access to any of the systems to mess with it myself.
 
Wasn’t really looking for ideas as much as I was curious if the aftermarket had any options. There are certainly multiple ways like pull a fuse, hidden battery disconnect, etc.

I guess I was thinking of the way the OEM JTEC works with the module in a Ram or Jeep GC where they communicate over a 2 wire network. If the module doesn’t get the unlock signal, it tells the PCM not to run and the truck shuts off after a second or two. Wondered if any of the aftermarket EFI systems could do something similar.

If multiple tunes can be loaded and switched on the fly, I could see something like this working. Just don’t have the experience or access to any of the systems to mess with it myself.
There are definitely all kinds of strategies you could employ with the Megasquirt. Using a 2nd fuel/spark table that cripples the car or puts it in a valet mode, a 2-step mode that just kills fuel/spark at a really low RPM, rev-limiter, etc. All of these could be enabled/disabled from an external input. To make it interesting and convenient I would want to control it with some kind of hand-held, wireless input; Bluetooth keyfob, Smart Phone app, proximity sensor (RFID or NFC or similar).
 
Maybe a bad tune that would crank but just barely run.
Back in the day (lol), some guys I knew pranking someone would switch 1 plug wire with the coil wire on the distributor cap. When the person came back and tried to crank their car, that one cylinder would fire making it sound like it wanted to crank but it never would.
 
Do you honestly think car thieves are going to take the time to try and figure out why it won’t run?
I do. Maybe that is way over thinking it. I used to replace plug and coil wires with bad wires to disguise their rigged anti theft purpose.
 
There's a bunch of ways you can do this, Dion, depending on the equipment at hand. There might be a wire in the ECU you can ground. If you run an MSD 6 you can ground the white wire. Otherwise, just put a switch, "not obvious" does not even really need to be hid. On a Holley just series into the main EFI power relay coil, or the pump relay coil. There are other ways.

I plan to run a trunk mount battery. There's a couple ways you can kill that.........aren't you running some sort of electric latching relay deal?
 
Maybe a bad tune that would crank but just barely run.
Back in the day (lol), some guys I knew pranking someone would switch 1 plug wire with the coil wire on the distributor cap. When the person came back and tried to crank their car, that one cylinder would fire making it sound like it wanted to crank but it never would.
How would it be in time to that one cylinder?
 
I plan to run a trunk mount battery. There's a couple ways you can kill that.........aren't you running some sort of electric latching relay deal?

I am, which is why I wasn’t really looking for ideas, more just curious what could be done with MS or some other aftermarket EFI.

If I end up running the OEM Magnum PCM, I will probably run the other little control module as well. Shouldn’t be hard so why not. But the idea of traction control has got me intrigued which made me curious if there was something that could be done with aftermarket systems.

The idea of a valet mode is kind of cool. I have never, and will probably never, have my car parked by a valet so doubt it will be useful. Oh wait, stayed at the Trump Tower in Vegas years ago and they only valet parked cars. But it was a rental minivan so not sure that counts.
 
I do. Maybe that is way over thinking it. I used to replace plug and coil wires with bad wires to disguise their rigged anti theft purpose.
Yea I think most people over think it. That’s why steering wheel clubs work. They are actually easy to break apart but when there is another car without one, why spend the time. Car thieves are mostly opportunistic, anything that will take time to “undo” will deter them. Of course with classic cars they might be after a specific model or make so they’d be a little more interested in making something work but a pulled ecu relay or fuel pump relay/fuse in a fuse box under the hood or in the car will work for 95% of the opportunity criminals. I have a smith&wesson for the other 5%.
:lol:
 
How would it be in time to that one cylinder?
The coil fires when the rotor is lined up with each of the 8 positions but when the coil wire is in one of the 8 spots, it only connects with the rotor one time out of 8. It then feeds backward through the rotor to the plug wire in the middle of the cap.
 
The coil fires when the rotor is lined up with each of the 8 positions but when the coil wire is in one of the 8 spots, it only connects with the rotor one time out of 8. It then feeds backward through the rotor to the plug wire in the middle of the cap.
Ok now I get it. You switch the coil lead and a lead for a specific cylinder. Makes sense now.
 
Ok now I get it. You switch the coil lead and a lead for a specific cylinder. Makes sense now.
A lot of the cars back then didn't have inside hood release. So it was an easy prank. And with carbureted engines, when that one cylinder fired, it was kind of like the engine may be flooded with gas so everyone usually just keeps on cranking hoping it will clear out and run.
 
Like Subcon said, the Megasquirt can do table switching via an external switch. Think of it like red key / black key on a modern Hellcat or valet mode. You could have one table be zero fuel so any would-be thief wouldn't flood your engine while trying to start it at least. A valet mode with just heavily reduced fueling could also work, but honestly I think that could do more harm than good. Better to just fully cut it and not even give them a chance. It would be effectively the same as pulling the fuel pump/fuel injector fuses, just via switch so you don't have to mess with a fuse every time you want to drive it.

What would be interesting, and maybe possible, would be to link the table switch to a CAN input. The Megasquirt supports CAN communication, so I bet you could probably get a keyfob style module that outputs a CAN signal that is your table switch activator. Then your "default" table would be the zeroed out one and when the module detects a keyfob it would switch over to the real table. The trick would be finding a module though. I have a feeling that might almost need to be a semi custom affair as it would have to talk via the CAN protocol the Megasquirt supports, so it may take some custom coding in the Megasquirt to work as well. That is one of the novel things about the MS though. You can pretty much do anything you want if you know how to write custom code for it.
 
Like Subcon said, the Megasquirt can do table switching via an external switch. Think of it like red key / black key on a modern Hellcat or valet mode. You could have one table be zero fuel so any would-be thief wouldn't flood your engine while trying to start it at least. A valet mode with just heavily reduced fueling could also work, but honestly I think that could do more harm than good. Better to just fully cut it and not even give them a chance. It would be effectively the same as pulling the fuel pump/fuel injector fuses, just via switch so you don't have to mess with a fuse every time you want to drive it.

What would be interesting, and maybe possible, would be to link the table switch to a CAN input. The Megasquirt supports CAN communication, so I bet you could probably get a keyfob style module that outputs a CAN signal that is your table switch activator. Then your "default" table would be the zeroed out one and when the module detects a keyfob it would switch over to the real table. The trick would be finding a module though. I have a feeling that might almost need to be a semi custom affair as it would have to talk via the CAN protocol the Megasquirt supports, so it may take some custom coding in the Megasquirt to work as well. That is one of the novel things about the MS though. You can pretty much do anything you want if you know how to write custom code for it.

That's exactly what I am talking about.

Can you do more than one table? Or is it one of 2 tables?

My first thought would be 3 separate tables. One standard one, one valet table with the rev limiter down to 1500 RPM and a no-start table with zero fueling. A lock signal uses the no-start table and a missing fob uses the valet one. So when you lock the doors, car won't start. If you toss the key to a valet (assuming the car doesn't have pushbutton starting) he/she could start the car but the missing fob would limit it to 1500 RPM.

Another option might be a full power table (red key) and reduced power (black key) for wife/kid/etc. But instead of a different fob, just use no fob at all and limit the RPM and/or reduce timing.

I have seen keyless entry and pushbutton start systems that use RFID tech. Not sure if it could be used though.

Cool stuff. The fact that MS can do table switching based on an input is enough. More than 2 tables would just be extra frosting on an already sweet cake.
 
Back when I worked on electronic access systems for businesses there were stand alone keypad and proximity card readers that had a switchable output and some ran on 12V DC. Maybe something like that could be used in conjunction with a MS system to trigger a red key fuel/timing map.
 
That's exactly what I am talking about.

Can you do more than one table? Or is it one of 2 tables?

My first thought would be 3 separate tables. One standard one, one valet table with the rev limiter down to 1500 RPM and a no-start table with zero fueling. A lock signal uses the no-start table and a missing fob uses the valet one. So when you lock the doors, car won't start. If you toss the key to a valet (assuming the car doesn't have pushbutton starting) he/she could start the car but the missing fob would limit it to 1500 RPM.

Another option might be a full power table (red key) and reduced power (black key) for wife/kid/etc. But instead of a different fob, just use no fob at all and limit the RPM and/or reduce timing.

I have seen keyless entry and pushbutton start systems that use RFID tech. Not sure if it could be used though.

Cool stuff. The fact that MS can do table switching based on an input is enough. More than 2 tables would just be extra frosting on an already sweet cake.

Hmm, I know there are actually 4 tables in the computer, but I believe the switch function is limited to just 2. The other 2 are meant as blend tables for something like E85. So you really only have 2 main tables, but each table has a matching blend table that it would interpolate between depending on the percentage of E85 a flex fuel sensor would detect. I guess maybe you could kind of trick that with a switch though. If it just blends tables based off of some analog input (probably a 0-5V sensor kind of deal), you could just set up a switch to send either 0V or 5V, so it would effectively "blend" fully to one table or the other.

However, you might be able to get clever as the fuel and ignition tables can be on independent switches I believe, and each of those has the 2+2 table setup. So in a way you might be able to get close to what you are looking for. The valet mode could swap the ignition table between normal and heavily reduced timing for reduced power and the fuel table could switch between "start" and "no start" effectively.
 
Due to recent developments on the site here with homebrewed traction control (@racerjoe @Map63Vette), I have been overviewing different aftermarket EFI systems just out of curiosity.

One thing I ran across was the option in one of the Holley systems to password protect your tune. This got me to wondering if there are any options to turn fuel on or off based on a pulsed signal?

I know, it's kind of a jump; traction control -> locked tunes -> theft protection. But that's how my mind works sometimes.

Seems like a reach, but just wonder if there is a way to trigger the ECU so it knows the car is "unlocked" and a start command is followed or if an un-authorized start attempt would result in either no spark or no fuel. Pretty much an OEM setup except in an ECU you have access to and control. Hopefully a password setup would protect that as well.

I'm a little finicky about this stuff. Had a friend who's car was stolen out of his garage so it's something that is on my mind. Nothing is perfect, even the new cars are stolen, but just seems like something to add difficulty. Just maybe give the opportunity to find the twit sitting in the drivers seat wondering why it won't run so he can "trip" a couple of times before the police show up. :)

Found one thread where the guy asked about a tune that wouldn't run (no fuel or spark) and then loaded with a handheld. Rather something that could be turned on and off at the push of a button. I've heard of dual tunes, does MSPro or a Terminator X allow for that?


I've seen aftermarket universal keyless ignition systems, push to start style. The ones I saw had a credit card shaped key you could keep in your wallet. While I'm not necessarily of fan of the push to start feature, there's no way someone could start it without the key card. Cool thing about efi is you can't just put a jumper wire to the coil and jump the starter. ECU needs to be on for eveything to work. Without the key card, the car won't move, unless it's on the back of a flatbed.
 
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