Interesting VR V8 ECUs

[Mikestech0]

Hi guys
I have an interesting one, I have just acquired x2 VR V8 Man ECU's service number 16183082.

My current ECU is a VR V6 Man ECU with a VS 185Kw HSV tune, VATS removed and fan output setup to run thermos.

I Put my Memcal in the first V8 Man ECU and tested, fans came on when the ignition was turned on and the motor idles at 1100 RPM... thinking limp home mode invoked???
The second ECU runs the motor at 1400 RPM and fans don't run, not sure why the motor is running higher than the normal idle??? IAC relearn???

Both ECUs were tested after leaving them for a while before running them, I haven't had a chance to check error codes on the laptop.

Just wondering if anyone else has come across these sort of issues.

The reason for using the V8 ECUs is because I thought I had a problem with my V6 ECU

Any help would be appreciated

[Dazza92VP]

sounds like it going into limp home mode only thing is you say that its a vr v6 and your running a 185kw tune hsv which sounds like a v8 tune which cant run a v6 due to netres being setup for v6 and the tune telling it its a different amount of cylinders ref angle is wrong for starters and what was the original issue with it that made you thing ecu is playing up?

[Charlescrown]

The ECU's are exactly the same for V6 and V8 and I agree it looks like it's in limp mode. Is the check engine light also coming on?

[Mikestech0]

Hi Guys
Let me start again as I think I made a mix up here

Project
: UC Torana
: VT roller cam motor
: VR or early VS wiring harness, MAP sensor, VR throttle body, 2 wire O2 sensor
: VR V6 man ECU with V8 memcal 185kw tune, mods are no VATS and A/C fan output controls thermo fans.

Problem
Had issues with the idle when cold, would hunt and stall, once warm its idles correctly and runs normal
So I loaned a friends ECU with the same tune, plugged it in and the engine ran very smooth and would idle when cold.
Thinking I either had an ECU problem or a memcal problem. I did however plug my memcal into my friends ECU and the motor ran fine, thinking this cancels out a memcal issue.

Went serching found 2 identical VR V8 man ECUs which haven't been touched, still had the BLFM tune, I was unable to used the memcals as they have VATS still on them.
I plugged my memcal into the ECUs and the below is what I found

ECU 1 fans running all the time and engine idle at 1100RPM, assuming limp home mode
ECU 2 Engine running at 1400RPM, assuming IAC re-learn.

I haven't hooked up the laptop to them yet to check for error codes, haven't had time.

Just wondering if anyone has experienced similar issues with ECU's

Hope this makes more sence

[vlad01]

Yeah it could be ECU 1 that is faulty. I once had a 808 ECU that just ran like a bucket of crap and had a constant code 51 if I recall correctly, was a memcal error anyway but memcal was fine, just refused to run with any memcal and gave the same memcal error everytime.

Just FYI, a readily available 808 will run your engine just the same except it has no built in high speed comms but you can add either USB interface board or the SXR board which converts it to have high speed and be the same as the VR manual ECU. I prefer the latter as you then have the USB ALDL adapter which you can use in other cars when needed and not be a dedicated USB just for your project. But since you already have a VR manual ECU no need, but nothing wrong with spares than cost less than the going price of a VR manual ECU.

[yoda69]

Where have you placed the Manifold Air Temp sensor?
In VR/VS was in the Manifold but VT ran an Inlet Air Temp near the MAF.
You will need to have it placed in the inlet manifold as per the VR/VS setup or you’ll have problems.

[Charlescrown]

Check for codes first then you'll know what direction to go.

[Dylan]

Where did you get the map sensor vaccum from? VT manifold doesn't have a port for that

[antus]

Agree check for codes. It sounds like the ones which are running are running ok, its likely there is one or more hardware faults. As Yoda says about the MAT location too. Quite possibly also an air or injector leak.

[Mikestech0]

Hi guys
Thanks for the info
The MAP is teed off the fuel pressure reg and the air temp sensor is in the air filter box.
The engine temp sensor is on the front of the inlet manifold right next too the torana temp sensor.
I have had all the injectors tested and they are all flowing correctly, when i put them back in i put new O rings in aswell.
The inlet manifold has be removed due to an oil leak around the dizzy area and all new gaskets installed.
New dizzy cap and rotor button, leeds and plugs.

I was told that the cam profiles are slightly different from VR non roller cam to VT roller cam, cant find any info on this. A topic for another day i guess

I work away so when i get home i will plug the laptop in and see whats happening,

Again thanks guys