RS_Matt

Just had a 3" Cobra 200cel Sports cat downpipe fitted to my 2003 WRX, I got the expected Cat below efficiency CEL pretty quick but was able to remove it with my code reader.

I opened the car up in 3rd gear tonight and got a fuel cut with a P0244 code letting me know that I'm getting boost creep.

Is this normal for a sports cat? as I've read all over the net that a sports cat only really needs a remap tweak to get the best out of it and that a remap isn't essential.

Will a remap cure the issue or will the car need wastegate modifications?

piehole1983

iTrader: (7)

Probably need the waste gate duty cycle reduced because of the free flowing CAT.

RS_Matt

Am I right in thinking running a sports cat downpipe works better on a non-mapped WRX as the ECU tolerances are wider?

fat-thomas

iTrader: (4)

Unmapped mods lol

piehole1983

iTrader: (7)

I'm not quite sure what you mean by the tolerances being wider. From my experience with self mapping on ESL, small physical changes to the engine, exhaust or fuelling components do require the map to be adjusted or at the very least checked to make sure all is well. What you have done is allow the turbo to spool much faster than the current boost map can control. That's what's causing the fuel cut and fault codes. Potentially it could be knocking away and smashing the big ends up. I'd get it checked asap.

Jolly Green Monster

iTrader: (4)

It's always wise to get it checked and mapped as required rather than assuming. Not only do I often see mods causing issues like lean or det but also actually losing power or finding that something else has failed or worn beyond safe. Like fuel pump, maf, vac hoses split or fitted wrong for example.

Simon

RS_Matt

Found the problem, every time I floor the car the wastegate vacuum hose splits.

RS_Matt

Already contacted you for a map tweak before I created this thread.

joz8968

iTrader: (13)

Great. Now don't floor it, till fixed!

Get that section of hose replaced ASAP, with the OEM black stuff (the best).

RS_Matt

I did, using the intercooler spray hose, it just split.

joz8968

iTrader: (13)

But are you sure it's rated at the same pressure as a vac hose? Surely the water pump's pressure is nowhere near that of a turbo's at full chat?!

For the sake of a few quid, I'd simply not take any chances and get a fresh section of the correct OEM stuff from a main dealer (or a specialist like RCM).

It's not worth it... A member on here lost an engine to a split vac hose, when hooning round The 'Ring.

RS_Matt

I chopped up the original vac pipe at first and it just split again but obviously it may have been too short.

I'll just plum in another piece of intercooler spray hose and stay off boost until I get the OEM one.

JGM after it gets a map tweak will the car pull like it does with the vac hose off?

RS_Matt

Is the hose for a TD05 and TD04 different?

Anyone know the part number?

fat-thomas

iTrader: (4)

Are you sure its not sucking the hose flat on boost?

RS_Matt

I'm not sure what is happening, all I know it was very hard to get the split pipe back on after I cut the split end off and the intercooler spray hose splits a little whilst you slide it on the actuator outlet.

RS_Matt

It was a 3mm internal diameter hose that was on the wastegate, pretty sure it should be 4mm. I think 5mm would be better but then it will be lose on the t-piece.

Can't win

fat-thomas

iTrader: (4)

the pipe is collapsing,nothing to do with the size more to do with wrong pipe for the job

Jolly Green Monster

iTrader: (4)

Similar yes. No fuel cut though and safe.

Jolly Green Monster

iTrader: (4)

Agreed its the wrong hose but its not collapsing as its under pressure not vacuum.

The side to compressor cover should have a restrictor pill in.

silicone hose works well. I often have to replace hoses before mapping as they perish.

RS_Matt

Agreed about not collapsing, I think when the tuner took my turbo off to fit the downpipe he probably partially split the 3mm hose when he put it back on. I've gone on boost a few days later and it's just given out. Same happened today with the 4mm intercooler spray hose, they just seem to tear at the top a little when you force it on the actuator. Might have to use some soapy water. :/

Ordered some 4mm silicone off ebay, hopefully it won't rip putting it on.

The original 3mm hose that split was marked AEM 04-35-06 written on it.

RS_Matt

I know it was dangerous when it happened but what kind of power would my car have made when it over boosted? it felt unbelievably rapid! Without the boost creep my car has never come close to pinning me in the drivers seat. It felt like if I'd let go of the steering wheel I would have been thrown in the back of the car.

It's currently around 310bhp on a TD05. Would the fuel cut have come in as boost rose just over 1.5bar?

Jolly Green Monster

iTrader: (4)

Forgot it was on a td05. Probably 330lb torque. It was the torque you would have felt. Boost cut is probably around 1.5bar yes.

Originally you gave the impression it was on the standard map as you said it had tolerance in for a sportscat. Therefore very little tolerance.

RS_Matt

I did mention a map tweak on post 1, 8 and 12!

I was just trying to figure out why some tuners on here said a remap wasn't that essential for a sports cat.

Jolly Green Monster

iTrader: (4)

Your first post suggests the car is standard bar this newly added sportscat.

What downpipe was fitted before you fitted the sportscat? I now don't know if it was mapped with standard downpipe or Decat.

Yes you mentioned tweak and I nearly corrected you that it would be a full map as the cars standard before the sportscat but decided that was being picky in criticising your workpding because you said in the first post (implied it was standard before sportscat).

You can't expect a car to be safe if changing mods to a standard car let alone one that's been custom mapped to match the mods it had before you changed the downpipe.

I believe I did reply to your message on Facebook but didn't known it was related to this thread at the time.

RS_Matt

But wouldn't boost creep that induces fuel cut be nigh on impossible with 2 other catalytic converters in place as well as a sports cat?

RS_Matt

Anyway I've got hold of some silicone 4mm ID hose from the kind chaps at Pumaspeed in Wakefield and it goes on so easy it defies belief.

Jolly Green Monster

iTrader: (4)

You haven't answered what cat or Decat or what ever was fitted when mapped.

Boost creep is the least concern. What you describe is not boost creep btw. You described over boost because the pipe was split.

The concern is it maybe lean, detting or possibly just down on power as it's not mapped for the new part which will effect flow through the engine.

Jolly Green Monster

iTrader: (4)

Make sure it can't come off as easy. Use cable ties or clips

RS_Matt

No cats save for one in the downpipe.

Basically I do my research before fitting any part and after. Things like de-catting the up-pipe and fitting a panel filter etc etc always get 50-50 opinions.

A few mods I've left without a map and a few I haven't, the car is on it's 5th map. A 6th may or may not be needed but I would like to find out for sure. If it doesn't I can get one after I've fitted headers etc.

As it stands I don't want anymore power increasing mods but that'll change the next time something like a clio pulls away down a slip road, to 60-70 of course.

Jolly Green Monster

iTrader: (4)

Problem is most of the opinions given are from a standard car not one custom mapped already and no offence intended to anyone giving an opinion but "it will be fine as mine has been for 80years and I have done a trackday with it" are meaningless as everyone drives so differently and every car is different.

You have gone from downpipe standard cat to sportscat? Needs checking as I presume thats from closed to open neck downpipe plia faster flowing cat.