Sale ends todayGet 30% off any course (excluding packages)

Ends in --- --- ---

ECU temperature

Off Topic Discussion

Forum Posts



Tech Articles

If it's not really about tuning or wiring. Then it belongs in here.

= Resolved threads


Hey guys i have a few questions. when a afr sensor goes bad will it just read a error code #. or can it read consistent lean or rich numbers also? (Innovate lc2) my car has had the same tune on it for a while no issues

my car has been running lean in boost randomly I thought it could be my afr sensor acting up. But I did a log and it fuel cut a 5k rpm. i did two pulls in third gear and the afr's where good all the way up to 17psi then I did a fourth gear pull and it leaned out as the boost increased. And then fuel cut for some reason. The Elite 550 doesn't have a lean afr fuel cut does it?? But

I noticed the actual ECU temperature was blinking red and was at 170°f. Not coolant or air temp but the ECU itself. Would this cause my car to randomly fuel cut? I'm not hitting boost cut & i just upgraded to a new aeromotive fuel pump and regulator a few months ago. No other issues i can see that would cause fuel cutting other than ECU temp maybe? Also is 170°f ecu temp to high to continue to drive the car?

Thanks for the help.

Hello when the sensor goes bad it can give all kinds of readings, not always just an error code but that is the most common thing

170f is too hot for the ECU, check where it is mounted does it get hot around that area from outside sources like exhaust etc, you would need to check the map for a possible lean out protection being set up. my opinion would be to swap out the 02 sensor if you have any doubt, then get some logging done to see what is going on

Regards Ross

Okay I have a haltech Elite 550 does this ECU cause any cutting or some sort of safety function if the ECU is overheating? Iv moved it to the floor board as it was underneath the glove box didn't really seem like it was that hot where it was but i moved it anyway. As far as the wideband I changed the sensor but im pretty sure it actually fuel cut for some reason that can't figure out.. unless these euc comes with lean protection? I didn't set anything like that up, but would the target afr page have been a part of that? Maybe the ECU noticed it was too lean an fuel cut?

you will need to check the settings but if you did not set it up then it would not be there it is not there as a standard-setting


Without knowing the specific Haltech hardware or safety functions the symptoms you describe - fuel cut - would suggest the injector drivers failing or maybe an internal thermal cut out. The injector and ignition drivers tend to be the highest producers of heat with an ECU therefore the most likely to fail 1st. Typical maximum board temperatures tend to be around 65celsius or 150farenheit, try mounting it to something that can act as a heat sink or with some direct airflow, if the problem persists then the ECU may need to be returned to Haltech for service.

Regarding the lean condition fuel cut I would suggest referring to the user manual or contacting Haltech directly for support.



You can check the settings under the 'O2' tab in the functions menu for your wideband. I don't believe they come with any kind of lean out protection enabled as there would be too many variables. 'DTC Severity' would also need to be set from none to level 1 for example. The 550 having single stage engine protection only. It'd be worth checking what you have set up under engine protection also.

Do you mean the power or status lights on the ecu were blinking or the digital gauge in the software? They do get surprisingly warm going off my logs of ecu temperature. Around 25C ambients here atm and I have logged 52C ecu temp after half an hour driving for comparison, ecu in a cool location. 76C does sound pretty bad though. Might be worth shooting Haltech an email to confirm if there's some safety feature kicking in?

Attached Files

We usually reply within 12hrs (often sooner)

Need Help?

Need help choosing a course?

Experiencing website difficulties?

Or need to contact us for any other reason?