TimoL Posted March 21, 2019 Report Share Posted March 21, 2019 So here's the full story, Few days ago I started having problems with the car running really rich. First I thought it has something to do with MAP sensor or FPR but I couldn't find any fault. Then I went to check ECU readings and I noticed battery voltage was stuck to around 11.5V. This would explain why the car was running too rich because the ECU adds too much injector dead time to PW. I'm 100% sure the alternator or battery is not at fault here. There was zero change in the voltage reading when I applied full electrical load on the system vs. load at all. This has been happening for a few days now. It's not the same reading it gets stuck to. And it's always on cold starts, but I haven't done that many warm starts. If I shut the engine down after a while and restart, the voltage reading is working again. I've attached a log from this morning when I started the engine and shut down a couple of times. After I saved the log and started the engine again the voltage reading started working. Changes I've lately to tune is to enable internal logging. The voltage reading got stuck again tonight. When I disabled the internal logging and saved the settings it started working right away, no restart was needed. I'm not sure if this issue has something to do with the logging or if the settings save triggered this fixing effect. Any thoughts? I can provide more logs or do testing if needed. But for now I've turned of the internal logging to see if it helps. -Timo battvolt_starts.zip currentConfig.pclr Quote Link to comment Share on other sites More sharing options...
Tim D Posted March 21, 2019 Report Share Posted March 21, 2019 I would use a volt meter to measure the battery voltage (at the battery terminals) first. This should be around 12 V with the engine off and no electrical loads. Then start the engine and check that it goes up to around 14.3 V (as part of your log shows). This will narrow down where the problem is very quickly. Hope that helps... Quote Link to comment Share on other sites More sharing options...
TechDave Posted March 22, 2019 Report Share Posted March 22, 2019 Batt voltage wasn't logged in that file, so that's not much help. Try doing a PC Log, it captures everything. Quote Link to comment Share on other sites More sharing options...
Tim D Posted March 22, 2019 Report Share Posted March 22, 2019 Dave, I initially thought that, but it is logged. See below... It's a bit strange though, if you type Batt in the parameter list, it doesn't appear as you'd expect! However, if you click on Batt Voltage, it's there! I can't explain that....... Quote Link to comment Share on other sites More sharing options...
Adamw Posted March 23, 2019 Report Share Posted March 23, 2019 Hi Timo, We have had this reported by a couple of users now, so we believe it is a bug. We havent been able to reproduce it in house yet last time I heard so I will pass your log on to engineering so they have more info to help find the problem. Quote Link to comment Share on other sites More sharing options...
TimoL Posted March 23, 2019 Author Report Share Posted March 23, 2019 Hello, I've been rather busy with my work so I didn't check this thread regularly. Thanks for all the replies. I checked the battery voltage one morning and it was about 14.5V after cold start, engine running. The ECU was showing about 12V. I have one 20 sec PC log that to took after about 20km drive. I tried various electrical loads by turning the lights and blower on or off. No change in reported voltage.I believe the reported voltage was wrong during the whole drive, it was running very rich whenever I had to stop or drive at very light loads. I also noticed that I can't use the search function for the battery voltage. -Timo batt.llg 23 minutes ago, Adamw said: Hi Timo, We have had this reported by a couple of users now, so we believe it is a bug. We havent been able to reproduce it in house yet last time I heard so I will pass your log on to engineering so they have more info to help find the problem. The ECU config file I posted earlier contains the settings that caused this issue. Maybe they can test using it? Anything else I can do to help? No problems since I turned off the logging, but I think it's a bit too early to tell for sure. -Timo Quote Link to comment Share on other sites More sharing options...
UrbanD Posted March 3, 2021 Report Share Posted March 3, 2021 This has not yet been solved I see, because I'm having the same problem. Occasionally ECU reads fixed battery voltage. This happens in approx. 1/5 of my drives. See in attached image. And because of fixed voltage dwell is off too. Car: evo 8 with link g4+ Any update on firmware regarding this? UPDATE: did a firmware update to the latest version and that seemed to have solved the issue. So for anyone else having this problem, update your ecu fw to the latest version and you should be fine. Quote Link to comment Share on other sites More sharing options...
don17 Posted October 16, 2023 Report Share Posted October 16, 2023 I am having the same issue on my supralink ecu, was there any fix ? Quote Link to comment Share on other sites More sharing options...
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