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Discussion Starter · #1 ·
So, I'm driving off after I installed my Invidia catless dp and I'm fine for like a half mile or so then I decided to WOT it and I hear the blow off valve go off louder than usual and my engine is cut off. I looked and I have 14.5psi which is the highest I've seen it run before. I restarted it and it was on but it was rough when it was running and had no control of the throttle at all. I have a Cobb AP and just tuned it to stage 2. Took some forums words for it and thought it'd be alright to run it and never had a check engine light at all for not having a cat.

From what I read about boost creep is that your fuel gets cut off too as a safety so you don't blow your engine.

Can I just reset my ECU and just not enter high boost and still drive it? and what solutions are there to eliminate boost creep?
 

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External wastegate will solve the problem. Also needs a dyno tune.

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Village Idiot
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So will resetting my ECU and not entering high boost bring my car back up to normal?
NO

If you are running a cobb OTS tune with a catless down pipe then you are not running the correct tune. Not running the correct ECU configuration is bad even when the car is just idling. From the limited information you gave us, this is the best answer you will get. If you want a more detailed answer please answer these questions: What year and model is your car? Exactly what modifications do you have? What tune EXACTLY are you running?
 

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Discussion Starter · #5 ·
So will resetting my ECU and not entering high boost bring my car back up to normal?
NO

If you are running a cobb OTS tune with a catless down pipe then you are not running the correct tune. Not running the correct ECU configuration is bad even when the car is just idling. From the limited information you gave us, this is the best answer you will get. If you want a more detailed answer please answer these questions: What year and model is your car? Exactly what modifications do you have? What tune EXACTLY are you running?
So my best bet is to just go back to the catted DP until I can get it tuned. It's an 05 WRX just a Cobb intake and the Catless DP from Invidia. I was running the Cobb Stage 2 when it all happened.
 

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Village Idiot
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Did you even read the MAP notes of what you were getting into? Cobb stage 2 Map is designed ONLY for use with an aftermarket CATTED DOWNPIPE, as stated in the map notes of the OTS tune. Please do your research in the future. You have one of two options as stated before. Either return to stock and stock map ASAP and drive; or park the car until you can get a professional tune for the catless downpipe you currently have installed.
 

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Easy fix.

Sell the intake and the catless down pipe.

Use the money toward a catted downpipe.

Then run a stg2 map for exhaust, no intake.

The intake is useless, the downpipe wrong; no logic in keeping either.
 

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So will resetting my ECU and not entering high boost bring my car back up to normal?
Sure for some time, then it will sense something's wrong and do it again, and again and again and the car goes bang.

If you want to run a catless setup you are gonna need an external wastegate and boost controller setup. The problem is the system can't bleed pressure off fast enough on the stock wastegate to safely keep your boost levels under control on a catless pipe.

My suggestion, having a catless DP, get a catted one, it's nearly impossible for me to keep the tips clean, and the car reeks of fuel and exhaust.

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Sure for some time, then it will sense something's wrong and do it again, and again and again and the car goes bang.

If you want to run a catless setup you are gonna need an external wastegate and boost controller setup. The problem is the system can't bleed pressure off fast enough on the stock wastegate to safely keep your boost levels under control on a catless pipe.

My suggestion, having a catless DP, get a catted one, it's nearly impossible for me to keep the tips clean, and the car reeks of fuel and exhaust.

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I'm sorry, but this isn't terribly relevant. The problem is that he's not even running the proper tune. Yes catless can cause boost creep even when tuned properly, but that's irrelevant in this case.
 

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I'm not following what's not relevant. His problem is over boost with a catless DP. The solution if he keeps the DP is exactly what I said. He can make the choice to go catted or catless.

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Discussion Starter · #11 ·
So will resetting my ECU and not entering high boost bring my car back up to normal?
Sure for some time, then it will sense something's wrong and do it again, and again and again and the car goes bang.

If you want to run a catless setup you are gonna need an external wastegate and boost controller setup. The problem is the system can't bleed pressure off fast enough on the stock wastegate to safely keep your boost levels under control on a catless pipe.

My suggestion, having a catless DP, get a catted one, it's nearly impossible for me to keep the tips clean, and the car reeks of fuel and exhaust.

Sent from my SAMSUNG-SM-G935A using Tapatalk
Yea I'm just gonna put the OEM DP in with the Cats, reset it, and run the stage 1 map I was running. Sucha PITA since this DP only lasted a day lol.

I'll get the CBE, external waste gate, and put the DP in and do it all in one shot for a pro tune.

I read some people put the stage 2 OTS Map and tune and came out fine and never had any problems. I guess I just got unlucky.
 

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The only true fix for boost creep is porting the internal wastegate and fitting a new closure, or adding an external wastegate. Boost creep is a pure mechanical issue due to the turbo not being able to evacuate enough exhaust pressure to allow for the proper amount of boost. While an external wastegate is relevant and is indeed a mechanical fix to the mechanical issue, its also $900 worth of a fix which many people can't shell out easily.

However there are "band aid" fixes. Protuning is one of them...you can increase the boost limit. Many Stage 2 protunes increase boost to 17-19psi. I was running 20psi on my first STI.

You can also mitigate the issue by running the correctly specified catted downpipe that the map notes state from Cobb. There is a reason they are specified. Remove the intake as well if the notes don't specify for an intake.

I do find it interesting that a 2.0L engine is boost creeping. That's pretty rare in and of itself. Creep didn't become somewhat common unless you had an STI with the 2.5L engine, or in 2006+ with the 2.5L EJ255s were going into the WRX.
 

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Discussion Starter · #13 ·
The only true fix for boost creep is porting the internal wastegate and fitting a new closure, or adding an external wastegate. Boost creep is a pure mechanical issue due to the turbo not being able to evacuate enough exhaust pressure to allow for the proper amount of boost. While an external wastegate is relevant and is indeed a mechanical fix to the mechanical issue, its also $900 worth of a fix which many people can't shell out easily.

However there are "band aid" fixes. Protuning is one of them...you can increase the boost limit. Many Stage 2 protunes increase boost to 17-19psi. I was running 20psi on my first STI.

You can also mitigate the issue by running the correctly specified catted downpipe that the map notes state from Cobb. There is a reason they are specified. Remove the intake as well if the notes don't specify for an intake.

I do find it interesting that a 2.0L engine is boost creeping. That's pretty rare in and of itself. Creep didn't become somewhat common unless you had an STI with the 2.5L engine, or in 2006+ with the 2.5L EJ255s were going into the WRX.
EWG looks pretty simple of a concept. From looking at the product it looks like an Uppipe with a blow off kinda. Just releases all that pressure before it enters the turbo.

I'm not too familiar with porting the internal wastegate tho. What's the cost of doing it and Doing the labor yourself and how long will it take to do?

I'm starting to sense I should work my way from back to front. CBE first then DP, then EWG. So would I run into the same problem with an exhaust without a resonator?
 

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Once you start messing with ewg and boost controllers and such you will have to get the car tuned at s local tuner.

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Discussion Starter · #15 ·
So I found the problem.

Unfortunately this all happened at midnight and I could see anything. The Y-pipe that is attached to the turbo came off. That's where that loud BOV noise came from. I looked at it around 6pm when I got off work and just wrench tightened the hose clamp and jumped it BC it only had 8.8V and it worked. No weird response from the engine at all.

I can't remember who it was that mentioned it was weird for the EJ205 to over boost but I haven't ran it in high boost yet but I'm gonna run it low so I'm not blowing off hoses.
 

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You're going to be fine with stage two, even catless. Despite what people on this site claim to say the control systems in these vehicles are rather simple. Nothing your car is reading after the cat (rear 02 sensor) has an effect on the fueling. These maps are off the shelf, meaning they are very conservative as they need to work on everybody's car. Stage 2 used to be for catless only, if you're not getting a CEL, then cobb didn't really rebuild the map they just changed the notes...
 

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Except it can cause boost creep because the flow difference. Nobody said anything about the rear o2 doing anything.

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Except it can cause boost creep because the flow difference. Nobody said anything about the rear o2 doing anything.

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You're right, they didn't, all they said was "Cobb stage 2 Map is designed ONLY for use with an aftermarket CATTED DOWNPIPE, as stated in the map notes of the OTS tune" and that running it even at idle would ruin the car, signifying that they don't really understand how parts effect their cars.

As was stated before, this is a 2.0L. It is highly unlikely to experience boost creep unless you remove the DP all together.
 
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