BigBoiMR2

This Log is after arriving home, then turning off Closed Loop Lambda and watching the output fluctuate at idle https://drive.google.com/file/d/14nE2p50g3HdDnDHS-Qd0hZPmQA2lJUzi/view?usp=sharing

power runs.llgHello, I recently installed an AEM Fuel Pressure sensor (30-2130-100) I wired the Sensor to AN volt 3, 5V Power from the ECU to the sensor, and the ground to the sensor ground on the ECU. I used new lengths of wire and crimped on new pins and spliced into the power and sensor ground at the ecu side. The sensor was reading properly and I had no issues, it would react to changes instantly. After driving for maybe 30 minutes the sensor voltage rises to a point where the sensor is reading above the actual fuel pressure. once it rises past, the reading will be stable at say 50psi until the actual fuel pressure surpasses 50 psi, then the sensor will read the correct pressure until pressure drops below this "floor". the floor seems to slowly rise up to about 54psi max. setting the readout to 0-5V shows the same behaviour. the calibrations are correct it seems that the sensor wire is picking up voltage over time. If i unplug the sensor the voltage drops to .20 but as soon as the pins make contact it will jump back up to the voltage it was at. It seems to discharge once the car sits for a couple hours but short periods of time it holds the voltage. The car is a 1988 toyota MR2 with a 3SGTE. the Ignitor is mounted to the transmission as I was getting too much interference to connect to the ECU when it was installed on the Firewall. Other sensors do not seem to be affected by any rising voltage either, The MAP and IAT sensors continue to real correct values after long drives. the ECU is grounded to the factory point on the Intake Manifold. Edit: The 5V output is stable at 4.97V the whole time. Hopefully it is something simple I am overlooking, I have attached a log with it working correctly. I will upload a log with the issue present also. Thanks for the help power runs.llg

I couldn't wait for the morning, Just got back from testing with the laptop logging in the trunk. the ECU disconnected maybe once in the trunk and a couple times while I was holding the laptop so those could have been cord movement . Watching my boost/afr gauge to stay in the cell ranges, then pulling over and using the mixture map to tune the fuel map worked great. bonus to this is no distraction in the cabin but the downsides are obvious. Everything seems to be working well now. Thanks again for your help.

I'll test it some more in the morning without the extension. Thanks for the suggestion.

Hi Adam, I am using BKR7E spark plugs. I was using a usb 3.0 extension but I am also having the issue without any extension connected directly to the supplied USB cable. The USB connector is the only non OEM connection to the ECU Thanks for trying to help me again!

I just reset the ECU to factory settings and made a new map on software 5.6.5.3338 and firmware 5.6.5.3389. It seemed to correct the issue, I was able to connect with the engine running and start road tuning the map from scratch again. 15 minutes or so later it disconnected and now it is constantly disconnecting again.

Hello, I am running a Gen2 3SGTE in an AW11 with the ST205 PNP G4+ ECU. I was able to setup the ecu and get it idling as well as tuned in the cruise area of my map. I am now experiencing terrible connection issues that seem to be getting worse. I have no issues when the engine is not running. The ECU will connect to my PC initially and I can monitor at idle but recently if I try to change the fuel map the ECU will disconnect. The ECU will also consistently disconnect under light load while driving, this seems to be more frequent if I have PC logging running but will still happen within a minute or two without PC logging. once the ECU disconnects I can occasionally reconnect by pressing F3 but it will disconnect again quite quickly and then give me an error message about the com port. unplugging and replugging the USB will occasionally work but not for long. If I do manage to reconnect and try to download the log file from the ECU it will go through the download process but come up with an error message reading "Unable to save log file due to corrupt flash pages" My laptop Is running windows 8.1 x32 bit, I have tried another laptop running Windows 7 X64 bit Initially The ECU was on Firmware 5.6.4.3240 and I was using the new PCLink 5.6.6. I fully uninstalled it and the USB drivers, I then downloaded and installed 5.6.5.3338b along with the USB Drivers. I have tried to restore the ECU to factory settings and I have updated the firmware to 5.6.5.3389 I have read through the connection help file and checked off all the boxes, I have cleaned and checked all of the grounds, tried different USB settings and I am stumped at this point. I have attached a log file that was running with the engine idling and then disconnected. I have also attached my current map file. I am probably overlooking something and I hope someone can point it out to me. Thanks ECU Disconnect.llg Toyota MR2 MK1.5 Modelled Fuel.pclr

Ok, pin 71 receives power from the Circut Opening Relay, which gets power from the EFI relay so I will check the voltage along the path and find where it is dropping. Thanks for the quick replies and helpful information, I'll update once I've found the cause.

Alright I just tested pin 71 and 1 and got 14.20 which is matching the ECU voltage in the pclink software. The battery at the time tested at 14.7

Thanks for clearing that up. I'll update once I've repeated the test properly

I had been using pin 61 as the main power for my tests and probed 1, 14, 23, 26 and 46 as the grounds. I will test again using 71 as the main 12v power. I have attached the numbered pinouts I am referencing. Thanks for your reply

Hello, I am still in the early stages of my tuning and trying to make sure everything is functioning properly before I fully tune my fuel map. I currently have the car idle and cruise areas safely tuned. I am running a Gen2 3SGTE in an AW11 with the ST205 PNP G4+ ECU. I was having inconsistent voltage issues that I attributed to ground issues. I added a second ground to the battery in the trunk and the voltage is holding fairly stable now but I am getting a few different readings depending on where I check, Ecu voltage in pc link 14.10 Alternator to chassis 14.58 Battery positive to negative 14.58 B+ backprobing to each of the 5 grounds on the ecu connectors 14.48 Is this somewhat normal? I have checked the grounds in the engine bay and they all seem secure. I am mostly concerned about the ecu reading lower than what I'm getting at the ECU pins with a multimeter. Hopefully someone has some experience with this. Thank you.