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I have just fitted GT2560rs, and Greddy / Trust Dumps and front pipe, this was matched to my existing 3" Cat back Jasma exhaust and Standard CAT.

The car still has the standard ECU, and is running very rich over 5000rpm (low 10AFRs)

After picking car up from dyno yesterday it ran like bit of a dog on the way home, as if plugs were fouling as it was put under load (which would confirm what dyno printout suggests), but later that night it was breaking down real bad and did'nt clear up at all, I had a top speed of about 60kmh, and after a little while the little 'Exhaust temp sensor light' came on.

A quick check underneath the car revealled, a huge amount of heat from the Cat.

Has the Cat melted...?

Would retaining the standard Cat have caused my initial AFR problems in the first place, and would fitment of HiFlow Cat solve it?

I thought the standard ECU would have coped better with fairly minor Turbo and exhaust upgrade...?

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running very rich = shitload of unburnt fuel comin out through the cat = burnt through cat.

The cats probably carked it as a result of the turbo upgrade.

First thing id suggest is get the damn thing tuned. Thos turbos will have completely different response and power figures compared to stock.

I am fitting these turbos also, and as a result, with the expected power figures, am upgrading my injectors and my AFM's. I should probably also upgrade my fuel pump.

So yes, before you go driving that thing around any further with a clogged up cat, get it tuned. If you get a new hiflow cat you will probably melt that through also :)

Not really what I wanted to hear... :)

I wanted to build HP up on this car slowly (to a max of 450rwHP) so as I could enjoy each HP increase & not get bored to quickly with it, but if I fit PFC as it appears I will need to, i may as well then fit the larger injectors cam gears and AFM's so as not to have PFC retuned again and again... :)

I had a few ignition problems with my new setup and it dropped a cylinder on me a few times and I had the same rough running (rich as hell).

My CAT overheat light also popped up a few times as well. When it all got sorted and went back on the dyno it struggled to make the same power and needed 5psi more boost to match the same outright power but was still down on average power.

The cause was found to be a literally melted shut cat.

Okay......since the first post I have driven to an Exhaust shop and had them remove old Cat....turns out it was fine, and not melted at all.

(although they did have to use an OXY to get it off, so I was'nt a wuss after all for not removing it myself! :P )

I now have a Decat pipe fitted retaining the exhaust temp sensor.

Car still ran like shit, missing, felt like plugs were fouling, would'nt really go over 60kmh.

Replaced plugs today, Old plugs were'nt in bad nick at all (HKS items) and seem to be burning well, except plugs 4 & 5 which were still a bit wet with fuel.

New plugs fitted start car, runs exactly the same straight up as it did before....ie not running on all cylinders.

So what next 'coil packs'...?

and what is the best way to check they are working on a GTR?

Initially I would have suggested the cat had broken up. I had one do it once and it blocked the rear part of the cat up.

Buy six short plug leads, unscrew the coil packs and connect to the plugs using the leads. As it's running carefully unplug each one to isolate the crappy coil if one is bad. Try not to get zapped.

Buy six short plug leads, unscrew the coil packs and connect to the plugs using the leads. As it's running carefully unplug each one to isolate the crappy coil if one is bad. Try not to get zapped.

Good idea, I was wondering how i'd get the length out of the coil packs to check for spark...simple really :P

hey psi if u find a coil not workin then switch the plug from another one to it and try it to see if its the coil, or it might be the igniter pack on the back of the centre coil cover, as mine recently shit itself suddenly and it would misfire and then run fine and then run like shit, and really weird, until i got a second one to try and it worked perfecto, if u want to try one i can lend you mine to test if u like, i live north of river (near joondalup)

hope it helps :P

cheers

Brad

no stock computers go like this: more air flow, more fuel and it's not a linear increase either so the more airflow you get the amount of fuel being dumped in grows exponentialy.

Okay, seems I have stumbled (whoops I mean 'Found') the problem :rofl:

During the process of checking the coil packs today i removed the Rocker cover panel to get to them (as you do) and happened to notice the plug on the 'inside' which plugs into the ignitor (?) was very loose, and when I attempted to reconnect it did'nt really seem to click in very well and is infact still a bit loose.

But I restarted the car like that...and what do you know, purrs like a kitten!

Took it for a drive around some of the backroads around here and pulls well thru all the gears.

Bloody cars!.....the problem was totally unrelated to all recent work really, but as it happened straight after dyno it had me thinking it was a fueling issue!

Thanks for all the help guys.... :)

Now off to wash it so I can 'finally' check out these bigger turbos etc :)

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