VSV6 ECU weird goings on.

[brett_jjj]

Thanks mate.Do you know where exactly on the car the ECU earths connect to the engine or body?Is it near the ECU,or is it under the bonnet somewhere.Or does it connect to the engine .Theres a couple of earth wires going to the heater pipe bracket on front of the engine.I also found another earth point on the body near the battery.Theres a few earth wires connecting to the body,along with an earth wire from the neg battery terminal.Could any of these earth points be the ECU earth point?
Also all the wiring is all original.Theres not one bit of bodgey or extra wiring anywhere on the car,so nothing has ever been changed or stuffed around with..

EDIT.The schematic you posted says engine earths ,I take this to mean that the 02 sensors earth to the engine,and not the body, yeah?Maybe the ECU earths to the engine too.

[Holden202T]

ok from memory my ecotec has an earth on the rear of the passenger side head, one on the front of the block somewhere near the water pump and thats about it i think

other than that there is the earth strap for the battery to engine mount bolt.

[brett_jjj]

Thanks mate,I will check out these and make sure they are clean first before doing anything else.Can anyone confirm that the shared earth wire causes the problem with the 02 sensor readings.And would I be better off running a completely seperate earth wire for the 02 sensor heaters?And Id like to hear some of you guys thoughts on how the earth fix will stop the interference if they are still sharing the same earth which is supposedly causing the problem in the first place..I just cant see how it would.Im gonna temporarily join all the ECU and 02 sensor earth wires and earth them to the body somewhere,just to see if the later ECU bin files still set any codes.I will post back what happens with it.Lets hope it works.

[Holden202T]

i didn't originally know the earth issue was because they shared the same wire ..... the thing i can't understand is, sooner or later they all earth together so i can't see how it makes much difference if they share or not.

[brett_jjj]

Thanks agagin for your input,thats what I was getting at, if something is earthed,its earthed,(unless theres a bad connection),I think its more to do with the bin files for the ECU than the ECU earths and 02 sensor earths.And if the ECU earth was bad,wouldnt all the ECU bins do the same thing.It just doesnt make sense.The original bin (BSTK) works excellent.The later VS bins all stuff up with bad 02 sensor readings,bad LTFT-STFT readings and set error codes 76 and 78.

[brett_jjj]

Well today I earthed the ECU earths and 02 sensor earths out to the body and engine and neg battery terminal.I also cleaned and rechecked all the engine earths.I also ran another thick battery cable from the neg battery terminal to the engine..I fitted up the newer bin into the ECU,went for a drive,and you guessed it, bad 02 readings,bad fuel trims,and error codes set.Put the BSTK chip back in,all ok again, good 02 readings and no error codes.It has to be something between the different BIN files. Both the ECU's I have here,came with the original BSTK bin file.Maybe ones that came with BWPJ or BTXP are slightly different and wont do this..I will have to get hold of one somewhere and try it to see what happens.

[vn5000]

Are you sure both o2 sensors are ok. Maybe one is a bit slow but still sending a signal and BSTK bin doesnt do as many checks as the others , or a flag is set to bypass certain checks ,so it doesnt set the error code.Maybe the other bins are more sesitive to a faulty o2 sensor .
Regarding the earth i would use the engine ,as this is what the ecu is connected to,otherwise you may create an earth loop .Run two seperate earths , one for o2 heater and one for signal.Also keep them away from ht leads.

[yoda69]

I'm not sure of the differences with the VS ECU's but the the BSTK & BTXP use 16210672 and and BWPJ & CKUL use 16199728.
Refer Dr Bob's site for details http://www.memcals.com/rcc_info_memcals.html
As much as they are both $51 code bins, there maybe some subtle differences to do with the ECU's, I thought these were mostly to do with transmissions but you can never be sure.
Below is the copy of BTXP that I have, see if it is any different to the one you are using, this will at least eliminate one more possible problem.

btxp5610.BIN

Has anybody else had any experince mixing and match bin's between different ECU's?

yoda69

[brett_jjj]

Thanks again for your time guys,I downloaded the bin file,I will compare it to my BTXP to see if theres any differences with the one I have.The bins I have came from the original holden bin files on this web site,so I reckon they should be ok.Both ECU's I have are 16210672 type ECU's.This still happens with either ECU connected.A guy from here has offered to send me a spare BWPJ ECU to try.That will be interesting.I will try the later type bins with this ECU,I will also try the BSTK bin in the later ECU,just to see what happens .I will post back what I find out when Ive tried this.I might have to get two new genuine 02 sensors as well to see if that makes any difference.The 02 sensors fitted at the moment are about genuine holden sensors,2 years old,and show around 10 cross counts (driving along) on both sides with the BSTK bin,but the later bins show one side has no cross counts at all,the other reading for the other side shows only 1 or 2 counts .Thanks guys.I appreciate the help.

[brett_jjj]

Well.I got hold of another ECU to try in the place of my BSTK ECU and BSTK memcal.It is a newer VS BWPJ ECU and BWPJ memcal.When I run the later ECU and memcal,the 02 sensor readings either stop altogether,or are low and are also completely different between the two 02 sensor readings side to side.As soon as I put the BSTK ECU and memcal back in though,the readings are all ok again.It also fails the Tech 1 02 sensor test with the later ECU and memcal,but passes it with the BSTK ECU and memcal.Ive tried the 02 earthing thing again,absolutely no difference at all in any of the readings with either ECU.I also still get code 76 and 78 set with the later type ECU.I dont get any error codes with the BSTK memcal and ECU.Has anyone got any more ideas about this please.