Help looking at VY Log

[Stringyweevil]

Hi Guys,

I recently got a second hand 190km vy ecotec motor installed by a wreckers as my old one developed a nasty rod knock. As soon as i drove it under the slightest load the check engine came on the dash. Took it back and they had a look at it, plugged it into tech 2 and said knock sensors, they changed them over and it was still showing check engine under the first acceleration. Turns out the engine is pinging/knocking and they blamed it on bad fuel in my car (even though i just filled the tank with caltex 91 the night before and my previous engine never showed any errors driving 40km with that same tank of fuel). So now I am trying to figure out the problem myself as they seem unwilling/unable to help. Using an ALDL cable and tunerpro there are no DTCs coming up even though everytime I drive it I get check engine on the dash after 30 seconds of driving (I know the check engine comes on while logging due to lack of communication with BCM, but it happens without cable plugged in) I took it for a short drive and logged the data. With my limited experience i can't seem to find any issues with the logs, O2 sensors seem to be working fine (varying up and down voltage) the short term fuel trim seems to go a bit high in either direction, knocks don't seem to be detected in the DTC (even though I have heard the engine pinging and check engine comes on). Can someone with a bit more experience check out the log and see if anything stands out? I have put new spark plugs in and checked all connections/vacumm hoses and nothing seems out of ordinary. Old spark plugs seemed grey but nothing burnt/white. THe MAF sensor is still my old one which was working fine, I think O2 sensors are still my old ones which had no issue.

test 3.xdl

VY Log

(100.08 KiB) Downloaded 319 times

Thanks!

[Charlescrown]

I am not the smartest one to be advising you but what I see is a small amount of timing being pulled after you take your foot off the accelerator. At that time the O2 sensors go very rich before the decel fuel cut starts. I don't suppose it's something like a hole in your fuel pressure regulator? Pull the vacuum hose off and see if there's petrol inside it. You also have a code logged for low speed fan.

[Stringyweevil]

Thanks Charlescrown I pulled the vac line off the fuel pressure reg while it was running and it was dry. Can you think of why the check engine would be coming on with no error code? are there error codes that a tech 2 can pick up that we cant with tunerpro?
The low speed fan code is the one that is always triggered when you are logging from the aldl cable something to do with BCM communication I have read.

[Comcal76]

have you checked and cleaned your earth connections on the motor.

[Stringyweevil]

No I havent I will try that tomorrow thanks Comcal