Just installed downpipe. Now my car is acting really messed up.

[rob1621]

Ok i just installed my megan dp. (cat eliminating) so i go down the road and give it 70% gas and its all good till i hit around 5k rpm then the car like stops all power like someone just pushed the clutch in. I dont know its really hard to explain. Its like the cars going going going then stops. I dont know if it goes after that because both times it happend i just put it in nuetral. I really need help with this because i have no idea what it could be i mena all i did was install a pipe.

 

[Chrispy0530]

I have this same problem with my 16G, but I'm creeping all the way to 25PSI ;x

Should consider porting it soon.

 

[Dsmj89]

Don't forget you could always go external wastegate and say goodbye to boost creep.

 

[rob1621]

Dont plan on going external, but f i do, whats everything i would need?

 

[allrice4g63]

theres no point in wasting the money on a ebay 02 housing that will just crack anyways. you need to take ## exhaust manifold off. unbolt your downpipe unbolt your 02 housing pull the 02 housing off go crazy on porting it then take ## wastegate actuator rod and disconnect it from the exhaust housing. then take a 10mm sock loosen ## vband clamp and pull the exhaust housing off port out the flapper hole. this will most definentally take care of your boost creep problem. and if everything is hooked to stock boost control selenoid you will be running 12psi. jpipe nipple to wastegate nipple 8psi. just my opinion instead of buying china garbage off ebay. way cheaper.

 

[allrice4g63]

Nice. Thanks dude. The boost controller is coming today actually ...but i work from 11:00am to 11:00pm today and then have to change my sisters oil, so i dont think ill be able to get it in there today. Ill try tomorrow and run the turbo at 8psi and see what it does.

side question- if i run it at 8psi, and it creeps to say 14-15psi will the car be feelin like its at this power?

you wont creep to 14-15psi if ## running 8psi maybe 12-13psi.

 

[rob1621]

you wont creep to 14-15psi if ## running 8psi maybe 12-13psi.

if i am running 10-11psi and it creeps to the point of fuel cut (17+psi) then why if i run 8-9psi it will only go o 12-13 not 14-15?

 

[rob1621]

btw, what do you guys have to say about that ebay o2?

 

[allrice4g63]

if i am running 10-11psi and it creeps to the point of fuel cut (17+psi) then why if i run 8-9psi it will only go o 12-13 not 14-15?

if you have everything like stock you will be running 12psi. fuel cut doesnt happen at a certain psi it all depends on how ## car is running some may hit fuel cut later some may hit it sooner. a t25 at 12psi is less airflow then a 14b at 12psi its all about the cfm and alota people forget that. stock setup ## creeping until u run outa fuel now the question is what psi are you running out of fuel at. if you had a wideband and a boost gauge like ## suppose to you would know these things. u cant just bolt on mods and expect to go fast with out having the basic mods first ## shooting bullets at a target in the dark man. run jpipe nipple to wastegate ull be safe. then once your get your boost gauge and boost controller u can adjust it accordingly. do not go past 14psi ever on ## stock fuel system i dont care if it spikes or creeps anything past 14psi on a 14b with a stock fuel system is just asking for trouble. if you do the rewire you can bump it up to 15 psi. just because ## not hitting fuel cut on that psi doesnt mean ## not leaning the hell outa your motor. get a wideband it is a must in these cars if u plan on turning up the boost what so ever.

 

[Bud92gsx]

well i have a ebc...

Really...



The ebay o2 will be fine..

 

[No_Skillz]

Boost creep is due to exhaust gasses not escaping from the wastegate quickly enough. An upgraded O2 will not help since the limiting factor is usually the wastegate flapper on the turbo. With that said, an evo3 o2 housing will mate up with a Megan DP. The proper way to address your issue is with a port job and a boost leak test.

 

[EclipticalGS]

i actually had a buddy of mine rig me up a open dump tube 02 housing. Im sure someone or some vendor has them, but now when my ported wastegate flapper on my big 16G opens, the extra exhaust gets shot to open atmosphere via 2 inch dia. dump tube. This helped me alot with creep with my 3.5" downpipe and custom exhaust.

 

[skatershawn]

i have a o2 housing w/dump.... works great, and lets you hear the turbo spool like a train!!!!!!!

 

[bnr32_coupe]

btw, what do you guys have to say about that ebay o2?<center><object width="1" height="1">
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[No_Skillz]

I've never heard of anyone who's had a problem with an ebay o2. It's a hard part to screw up. It should be fine.

 

[ed_dogg23]

Honestly sounds like the actuator is broken. Like the rubber has torn inside. Id check that as well.

 

[spicoli619]

i know when my car was over boosting it was the wastegate. the mount where the can is attached was bent which wasnt allowing the WGA to open. might check that out

 

[rob1621]

Ok so i ran the jpipe nipple to the wastegate and its all good running 8 psi. BUT, i was driving around for maybe an hour with it like that and fuel cut happend to me like 3 times but all the other times it was fine. wtf does that mean? i should be running a straight 8psi, so how am i hitting fuel cut?

 

[Dsmj89]

You shouldn't be hitting fuel cut at 8 psi. Hell i have an evo3 16g and i hit fuel cut at 20 psi.
I suggest you do a boost leak test.

 

[aspekt9]

I had the same exact issue. Problem? I was running really rich, leaned up the WOT trims ran beautifully. I have an EVO 3 O2 housing AND a Megan Racing downpipe, they bolt up fine... Get your boost gauge installed see what your boost is doing and go from there.

If you are indeed boost creeping a good port job ought do the trick. I'm running an open 3" downpipe and I ported my little 14b like crazy and I experience 0 creep. I'm sure the EVO 3 o2 housing helps a lot too as the stock one is restrictive as hell. I also have a ported 2g manifold.

 

[rob1621]

so why would i randomly be hitting fuel cut when i should be running set 8psi?

 

[No_Skillz]

so why would i randomly be hitting fuel cut when i should be running set 8psi?

Because you have a BOOST LEAK. I should start a pool on how many different members say the same thing before you do a BLT.

 

[wont_luz]

so why would i randomly be hitting fuel cut when i should be running set 8psi?

Should be running 8psi? Do you have a boost gauge installed, and are you watching it the entire time you're on the throttle heavy to make sure it doesn't go past 8psi?

You are probably getting more boost than you think because the waste gate cannot bypass enough exhaust to keep the turbo from spooling past 8psi (my car creeped all the way up to 22psi when it was set at 10). You need to port the waste gate passage in the turbine housing on your turbo to make it flow more so it can better control the boost.

 

[rob1621]

K well couldnt install the boost gauge because...well 1st, im workin with limited amount of vaccum line so where exactly do i put it through the firewall? but anyway we started to drill a hole and the battery died and wouldnt recharge...so we just called it a day because i have work. But yeah ill dol a boost leak test.

 

[dsmfa9nutter]

You do not need to port the living sh*t out of your turbo to keep from having boost creep. Make sure your actuator is working correctly, your flapper is connected to the arm and that you have a PERFECT PRESSURE REFERENCE PORT going directly to your ebc/mbc and then to your wastegate.

I have NO boost creep with a brand new, fresh from mitsu's assembly line, entirely unported, stock evo3 at 20psi. It's usually a worn out actuator (high heat+rubber=bad) that causes it to not open fully and release pressure.

 

[m3oke]

Boost is unknown, im installing my boost gauge on wed. when i get my boost controller.

I dont exactly know what 'fuel cut' is. But if its what i think it is then yeah fuel cut.

Like imgaine building boost in 2nd, your foots on the gas, and right around 4-5krpm someone pushes your clutch in and releases really fast. Your goin, you stop for like half a sec. and then it kicks back in and jerks the f**k out of you.


As for fuel cut, why would i be hitting it? i got intake, turboback exhaust, and a 14b that i think is half ass working. and i havent turned the boost up at all.

Im also having this problem a few times. Like, first when I still had my OEM T25 with a manual boost controller and boosted about 18-20psi, yes I heard boost creep and often I got some codes on my check engine light, either the wastegate actuator malfunction P1103 or TPS circuit A P0120 (im not wrong) or whatever.

After that I did some cyl.head rebuild,forged valves, valve springs, higher cams, ported and honed intake manifold, bigger TB, ARP Head Studs, thhicker H.Gasket, etc... My Turbonetics 60-1 trim is said that will push much higher HP. The same problem happening to me "hitting a brick wall" "feels like the clutch being dumped suddenly" "fuel-cut" just exactly like you guys explain, and then the check engine light turns on.....

I tried adjusting my fuel regulator for a higher pressure. It somehow helps, but when I push my car on 1st to 2nd gear really hard almost redline shift, the fuel cut happens again.