ThunderMax Tuner Problems And Step By Step Solutions

You go through stage 1 and 2 upgrades hopping to run your Harley smoothly and better than what it used to be. Whatever you do you need to tune it to the latest map. So, many people get the ThunderMax tuner.

The problem is, sometimes, it does not work as it supposes to and you are not alone who is dealing with ThunderMax tuner problems.

It may appear in different forms for various Harley enthusiasts. So, I have listed some common problems and later in this article, I have talked about solutions to fix those issues.

Common ThunderMax Tuner Problems

fixing ThunderMax tuner problems

Out of so many reliable fuel management systems for Harley Davidson from the trusted brand if you pick ThunderMax with tuner, more likely you will face such issues.

It may appear right from day one or within the first few weeks. Let’s see what you are facing or will face in coming days:

  • If tuner will keep saying to run the Auto-Tune even though you already did it multiple times in a short time.
  • The speedo hangs at some certain K’s and until you unplug it, it won’t reset.
  • After the successful installation of the Thundermax tuner, you just realized the starter switch is doing nothing.
  • Unsmooth engine when revved.
  • It feels like the tuner is not reading the temperature correctly.
  • On its own, sometimes, it takes itself out of the closed-loop. Since it runs on open-loop on its own, it may mess up your O2 sensors on the exhausts. Now, your bike is not running just right.
  • Even if it seems running okay for a few days, you are noticing the O2 sensors are burning hot. Sometimes, the front O2 sensors go through the same situation.
  • It seems the battery is doing nothing to turn over the motor.
  • After installing it successfully and as instructed, it is not responding to the ECM. It keeps saying no module was detected.
  • The engine head temperature becomes too high. The tuner software displays trouble code of front and rear EGO and says it’s too high.
  • Sometimes, you just can’t connect it to the program.
  • Your bike gets hot – so you turn it off. But when you try to turn it on, the ECM fuse gets blown!
  • It keeps backfiring through the air intake. You get constant decal popping.
  • Cold start-up gets very serious. Just leave your bike overnight and it becomes very difficult to get it started.
  • And the list gets bigger and bigger.

ThunderMax Tuning Tips & Probable Solutions

I know it may sound harsh, but you made a mistake getting the ThunderMax Auto-Tune in the first place. You would have such problems if you would get yours from a trusted brand like Vance & Hines.


Follow the below-mentioned tips to avoid such problems:

  • To fix the starting problem, whatever you do, never try to start it by manually opening the throttle.
  • For fresh installation, the Auto-Tune system needs the bare opportunity to make the necessary adjustments. To fix the lazy initial start, make sure you followed all the installation steps word by word. Make sure all the connections are secure and when the key is ON, check whether the fuel pump runs.
  • In addition, make sure you have loaded the desired map to the module. By the way, does it have the ability to link to the module? It is important to check even if the engine starts but it idles very poorly.


  • Idle tuning is okay initially and you need to make sure the temperature is et between 225 to 270 degrees. Warm up the engine up to 250 degrees and turn it off for 3 minutes. Then start it again and let it sit for another 3 minutes running idle.
  • Repeat the above procedure for at least 4 times.
  • Go to the main menu, then map editing, and do an auto map. If the problem still persists, perform the auto map operation 2 more times.


  • Perform the idle tuning first as mentioned above to proceed with this tuning.
  • During such a situation, you need to perform a kickstand tuning. To do that, keep the temperature between 225 to 270 degrees as before.
  • Again, warm up the engine to up to 250 degrees and very slowly throttle it.
  • Hold it for 5 seconds on various rpm like 1280, 1536, and so on. Do the same thing 3 times more.
  • Then turn off the engine and perform an auto map as described above. Notice whether the AFR gauges bounce to the green zone. If not, apply throttle again as described just above.


  • Inspect for any intake air leaks. If you need to replace the intake, get air intake from trusted brands
  • Inspect for any cracks in the exhaust system.
  • Replace spoiled or old gas.
  • Check the fuel pressure.
  • Service the plugged fuel filter.
  • Double-check all the connections again.
  • Clean the dirty throttle body.
Summing Up

Drop a mail to the ThunderMax Customer service describing your problem and see what they have to say about it. Only then try to fix it yourself.

Apart from the above-mentioned ThunderMax tuner problems, you may have a different one. But sequentially troubleshoot it as described above. In my experience, most people can’t install it properly. So, here is an installation video for you.

5 thoughts on “ThunderMax Tuner Problems And Step By Step Solutions”

  1. I have pinging when I accelerate between 2300 to 3000 rpms throttle is 25% or higher. I’m wondering is timing off or what can be done to fix. I sent a down load reading to thunder max

  2. I am one of those who purchased the thunder max there are alot of issues with the set up i went on a long ride and the bike has been running like crap i have reached out to thunder max and i feel like i am getting the run around i am going back to FP3

  3. I have a Harley Davidson crossbones 2010. I bought a thundermax 309-460. I have built-in supetrapp fishtail exhaust with a built-in damper for sound adjustment, a sports air cleaner and an S&S 510 camshaft. Which thundermax folder needs to be loaded for the engine to work perfectly?
    Thanks for your answer.
    Kind regards,


  4. i innstalled the thunder max about three years ago and from day one i have always had pinging at highway speed under a load thunder max has sent me 4 different tunes with no luck. i am also pretty sure that it is running rich because of the brown crap on my exhaust pipes

  5. Hi. Recently bought a 2006 Harley Deluxe with a stage 4, Zipper 577’s, stage 2 pistons, head work etc. The bike pulled like a monster from 2800 on the first week or so, now it seems to have lost all power when on the throttle. Still runs well and doesn’t seem to have any hiccups besides the lost power. I did add some quiet baffles into the V&H Longshots for a brief period but removed them when I noticed the lost power. Was told by TM rep to give it a couple hundred miles to settle back in with the stock baffles. I’ve gone through 2 plus tanks of fuel and no change in performance. I do have a serial cable on order so at the moment I can’t retrieve any info. It’s the 309-340 model. Still at a loss for the lost power though. Thanks for any input.

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