Need Help Please.

[nathen]

Hi guys,

I have a really weird issue that has happened and hopefully someone can tell me what is going on.

Firstly my car is a ba xr6 turbo that has a custom tune ,wog cooler dekas, the car makes 300rwkw.

Now I have had this tune for nearly a year now and never had an issue with it tuned at c@V, it would always spike to 15psi then hold on 12psi this is how it was setup in the tune.

the misses filled up at shell with vmax.

now the problem part!!!

she gave the car a boot up the hill just after she filled up.car was on boost then back fired!!!

got the car home and it was running like a busted arse.wont rev past 3000rpm and as soon as boost comes on runs fine until 5psi then starts jerking and splutters!!! get her home in driveway car revs no problems 4000 rpm..5000rpm starts to cof and splutter

I ran this tank of fuel all the way out and filled the car up with the 98 octane fuel from caltex and then gave it a boot to see if the issue was still there, to my suprise it was.

next day removed all cooler pipes cleaned throttle body done boost control maintance,replaced all plugs checked all hoses.

problem still there.

next day drove down to my mechanic mate.he test all coils found 2 stuffed coils put checked for errors in ecu nothing came up??checks cat no problem

then replaced fuel filter still nothink car still splutters and carrys on.

today I replace oil and filter recheck all plugs check turbo bolts manifold bolts I remove bov thinking it could be the bov not closing properly.still no fix

Does anybody know what this can be, can bad fuel cause these problems? Or can it be that the wastegate is on the way out?

im about ready to sell the car im over this!!!!

[Brods]

Sounds like a effed cat.

[nathen]

looked at that no problem

[ratter]

so has it got new plugs and coils?

[Worm]

My thoughts too! Replace all coils and plugs with new ones...

If you have, one of them may be dodgy...

[nathen]

yes guys replaced all plugs and gabbed to .080.

mechanic replaced 2 of the coils but car has got 88000km.just waiting for my new ones to arrive

[John_K]

You say you checked the cat. Did you actually unbolt it to check it?

One of my mates had similar symptoms to yours. We checked everything over 6 months.

Then eventually, he decided to unbolt his cat to make sure. Sure enough, the internals had somehow dislodged and jammed itself sideways.

It didn't rattle when we banged on it as it was in there nice & tight!

[nathen]

no john I didnt unbolt it mate.

hopefully my new coils will arrive tomorrow.

if its not the coils I will be taking it to get the cat swapped.im booked into c@v tuesaday to see if they can sort it but fingers crossed its the coil packs or cat.I dont want to have to fork out $800 for a new xcal unit then dyno time and new tune!!!

im about ready to sell the car and buy a ss.

first time the car has done somethink but im stuffed if I know what it is

[PSI40L]

Mate check all vacuum hoses the ones that go the plenum that they hAvent popped off or split doesnt sound like anything major it is easy to over look some things can u hear any leaks in air . Worst case do a comp test or leakage test should find your problem

[nathen]

checked all hoses again.

I let the fuel in thne tank get to a 1/4 car played up baddly.

limp the car to the servo put fuel in car came ok but still wouldnt boost over 5 psi.

going to get cat checked out after lunch.

im also considering pulling the fuel pump cradle out and checking to see if there is a blockage in the fuel pick up