*hello guys my jag runs a bit poor so i have some fueltrims and these are not good ive heard bank2 was bad maybe a vac leak or a o2 sensor now how do i test the o2sensor before taking the intake off and go look there and can someone tell me how a good trim looks like and how you can see why it could be a vac leak ? The car is a jag xjr v8 97' ive got this info :RPM 645 .in park idile short term bank1 : 0,0 long term bank1: 10,9 short term bank2 : 1,6 long term bank2: 5,5 Maf : 5,0g/s inlet temp 11degrees celcius . Now at 2522 Rpm short term bank1: 2,3 long term bank1: 8,6 short term bank2: 2,3 long term bank2: 3,9 Maf :17,4 i hope you guys can help me out if this is good or bad and why or what could cause this. The car had some mods lowwer and upper s/c pulley change electric coolant pump upgrade Thanks

 

I can't see it throwing codes and if it's a leak it's quite small. Why are you worried?

 

No got no codes from the car but the car starts poor sometimes and car holds back @ around 3000 rpm on highway and when driving slow and give it half throttle or kickdown it makes a rumbling sound and holds back.