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Just had a thought did you change the knock sensor to a Buick one or just plug into the ecotec one cause they are not the same and will pull out 9 degrees of timing

Thanks for your patience, Sorry for delay in getting back leg is OK now

i found the fault with the CEL light (bad connection) code displayed is 12 which i believe means all is good
which it is not!

Knock sensor is the VP

regards

robkeith wrote:code displayed is 12 which i believe means all is good

This is a common misconception. Code 12 simply means the ECU is good, not that "all" is good. Everytime an ECU is checked for error codes a code 12, regardless of any other codes being displayed, will always be displayed IF the ECU is ok. Did you leave the jumper in long enough to see if other codes are displayed after code 12?

Incorrect, 12 means everything regarding sensors, actuators, igintion module and operating parameters of the whole system including those within the ECU are ok, so yeah 12 means generally 90% of the power-train operation is all good.

There are a few instantiates where mechanical, ignition or fueling issues can not disrupt things enough to throw some sort of error.

If it runs like shite and there is no codes, there could be subtle issues elsewhere in calibration or mechanical/ignition/fueling. Start with basics. connect up to TP and have a look at the data for obvious, look at commanded values vs tables vs what you actually get, thats a good starting point.

unfortunately dont have hardware to connect to TP5 at this stage

soon!!

I wouldn't be surprised it its false knock as every V6 I have ever worked with an owned has false knock which killed all the power once warmed up as there is a scalar for knock retard enable temp. So it only becomes active once the engine reaches a certain temp. I think it was 68ºc iirc ?

You'd want to be careful with ecotecs and any actual knock though as they are extremely fragile. Pistons shatter at the drop of a hat unlike the army tank pistons buick have, they take a LOT of punishment.

vlad01 wrote:Incorrect, 12 means everything regarding sensors, actuators, igintion module and operating parameters of the whole system including those within the ECU are ok, so yeah 12 means generally 90% of the power-train operation is all good.

Not incorrect actually. I have seen many times ECUs flash code 12 then flash other codes.

MAGP,

i did wait for quite a number of cycles but only ever got the '12' flash count

rgds

hi vlad.

im suspecting lean out at top end as i detected a rattle when going up a hill whilst on petrol and switched to gas, and rattle stopped?

will have to get the interface cable and check

regards

robkeith wrote:MAGP,

i did wait for quite a number of cycles but only ever got the '12' flash count

rgds

Each code should flash 3 times e.g 12, 12 12, 35, 35, 35, then if 35 is the only fault code it will go back to 12, 12, 12, 35, 35, 35, and keep cycling in a loop.
If the only code you are getting is 12, then the ECU should be fine and the ECU system is working as it should.

robkeith wrote:hi vlad.

im suspecting lean out at top end as i detected a rattle when going up a hill whilst on petrol and switched to gas, and rattle stopped?

will have to get the interface cable and check

regards

You detected a rattle? and it went away on gas (I'm assuming you mean LPG?). LPG has an octane rating of 105-110 while regular unleaded is 91. Sounds to me like you've got detonation under load, which indicates to much timing in certain parts of the timing map on unleaded.