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hi guys

i'm trying to diagnose my sister in laws car.

she has an alloytec with 250k on the clock.
she dropped off her car saying its vibrating like hell on idle and no power.

i put the tech2 on it and pulled p0150 and p0050 - so i replaced the pre cat o2 and cleared the dtc's and they havent come back on but the car is running rough as still on idle and acceleration - the car shakes while idling and hesitates when taking off. i think there is a cat thats failed?
when i put the scan tool on and look at the fuel trims at 2500rpm they are fine within a couple of percent between each bank

however when idle bank 2 ( where the o2 was changed ) short term trim is running really high at 11% while bank 1 is at -1% so would explain the roughness.

i cant locate any vacuum leaks so running out of ideas

any help would be appreciated - i'm going to pull the cat off and have a look but i dont think it's that

attached is a log of the scan - i had to rename it to.csv as .html isn't allowed but rename it to .html to view

What model is it?

Have you checked the purge canister valve?

Hi it's a vz 05 Leo engine code

The purge Valve in the passenger side of the engine ticks away when it's active - that I have noticed but didn't think it'd be the cause?

I just pulled the cat off on that side and it looked good, no rattles and the cells are in good condition

I had one that did a sort of similar thing, it jumped a tooth or two on the left bank and through the cam position out.. Didn't log any correlation faults either! Doesn't rattle on start up?

nah no rattles - starts up fine and the fuel trims are good once above approx 1200rpm.

starting to do my head in now :/

The purge canister valve must be in the closed position when disconnected, remove from vehicle and simply make sure you can't blow through it, if you can then that's not only a big vac leak but also an extra fuel source that makes them run shit at idle.

I agree with oss96, I'd be checking the cam timing, they don't have to rattle to have jumped/stretched.

Thanks guys, I'll give the canister a go shortly and see what it's like, hope it's not the cam tooth as mentioned :/

my brother has my old VZ ute, and its doing similar, sounds rough as at idle, bring the revs up a bit and its ok, it also seemed to be smoother when it first starts, like once a cam tensioner gets oil pressure it puts the timing out .... BUT we haven't done much more than to park it up and forget about it lol....

it did have cam phasing DTC's though.

Turns out was a dicky coil pack causing the problem.

Also replaced the plugs as well but no more issues now

aceycv8 wrote:Turns out was a dicky coil pack causing the problem.

Also replaced the plugs as well but no more issues now

Don't suppose you can remember what exactly was wrong or how the coil pack was failing ?