Z22SE Heeeeeeelp :(

OK so here's the deal:

Vauxhall Vectra (52 plate "b") 2.2 CDX
K&N panel filter
Derestricted air box / 3 pipe mod
FPR vacuum pipe on inlet manifold
NGK PTR5A 10 spark plugs (was Bosch hlr8stex triple plugs)
2nd hand latest model GM coil pack
Klarius metal matrix cat (from the look of it seems to be sports cat)
Hoffman race tube
Pipecraft twin exit exhaust split straight from race tube to 2 boxes, 3x5 oval tail pipes

I've attached Torque "TrackLog" data for inspection. Sorry about the useless sensor data in parts. Still experimenting with what sensors actually give results and what don't lol.

Thing is the car seems really bogged down on WOT from lower revs more so when it's hot than normal weather like it's holding back big time for some reason. Regardless of intake temperature or coolant Temperature really. Makes a little difference but not enough for me to care.

I've noticed my long term fuel trim tends to sit around +10% which denotes compensating for a lean condition I believe.

Regardless of what I think; based on the info given about my cars spec and the info given from Torque, what the hell is going on with my engine!?

https://1drv.ms/x/s!Aq2rwQoL1GZ8hD_M9z_eGmS-Q8ng
 
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vocky

Staff
might be worth replacing the mixture lambda sensor

can also be the air intake sensor, coolant temp sensor or MAP sensor
 
Mixture Lambda was replaced but it tapped the floor and had a bit of a rattle after that. I used my old diagnostic sensor that also was replaced as a process of elimination and changed the plug over so as far as I'm aware it should be fine. Do the numbers suggest otherwise?

The temperature sensor has been replaced along with the thermostat. Both brand new but not GM. Thermostat is from Courtenay but CTS is "Vemo" from Euro Car Parts.
 
I've noticed the first Lambdas waveform isn't uniform very often. The extremities are about right but it doesn't actually zig zag too much. More tends to hang around a little or drop off really slow for the first 10-20% then drop quick. Or hangs about down the bottom end etc. Just random lol
 
And today it finally takes the guesswork out of it lol EML for front lambda heater circuit malfunction. I assume if that's malfunctioning the chances of the sensor working 100% is pretty slim?
 

vocky

Staff
I would recommend you buy a NGK lambda sensor, they are OEM suppliers and will last a long time. The cheap sensors tend to fail after six months
 
OK so here's sumat new! I decided to try putting the fuel regulator vacuum hose back onto my intake instead of the inlet manifold and it has improved the performance some. It's not as powerful on top end but seems to have more torque. Also I've noticed the fuel trim has gone from +10% LTFT and sometimes as much as +9% STFT to around -3% LTFT and +3% STFT most of the time.

Any ideas lol
 
K so I've removed the front bumper and also the pipe that runs behind it as well as the weird canister in the front of the wheel arch that seems to do nothing but obstruct air flow. I also then noticed a slight drop in torque although top end is quite obviously benefiting from increased breathing space. I moved the vacuum pipe back to the inlet manifold and sure enough I've slowly crept back to +12% LTFT!!! However the car is a lot more responsive than before on lower revs and a lot more responsive than with the vacuum line on the air intake. Ideas? Lol
 
Oh also that weird backfire/hesitation only seems to happen when vacuum pipe is connected to manifold, NOT when connected to intake :/ wth guys?! Vocky??
 
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