boost problem, help and opinions would be appreciated
Apr 11, 2017, 04:59 AM
#1
Newbie
Thread Starter
boost problem, help and opinions would be appreciated
hi guys,
short story:
my evo x gsr wont go above 14 psi of boost and tappers down to 12-13 PSI at 5000-6000rpm.
I did a boost leak test and nothing was leaking.
and now it threw a code p0171 lean condition.
Long Story:
i recently bought an Evo X with the following mods:
AMS Intercooler and hard pipes
AMS CAI
AMS DownPipe
HKS SSQV4 BOV VTA
Tomei CatBack Exhaust
greddy profec B spec 2 Manual Boost Controller
at that time the car was boosting 14PSI only so i figured the MBC was set to this. My plane was to ditch the MBC and reconnect the original Solenoid, and i did. and put an OTS map from Cobb (Stage 1 v403 +sf 91OCT (Normal Wastegate)). the boost didn't go up. at 3000rpm reaches 14PSI but above 5000RPM around 12-13 PSI. the car Idles at around -9.9 PSI
so i started simple and went to a shop the "supposedly" specializes in Evos and performed a boost leak test, he took the cone filter out and put his fitting and pressurized the system, no leaks where found. on my way back i did a pull on 3rd gear, and just after it the Service engine soon light came on, i pulled the code and its p0171 (lean system).
the car doesn't hesitate or act, just not powerful enough on high rpms.
what im thinking now is:
faulty boost solenoid
bad wastegate/rod/turbo
exhaust leak on the exhaust manifold
bad CAT, although its the stock one, im thinking this because the BOV is VTA so i figured lots of unburned fuel goes there is ruin it.
ur opinions and help would be much appreciated.
Thanks.
2011 Evo X GSR USDM.
short story:
my evo x gsr wont go above 14 psi of boost and tappers down to 12-13 PSI at 5000-6000rpm.
I did a boost leak test and nothing was leaking.
and now it threw a code p0171 lean condition.
Long Story:
i recently bought an Evo X with the following mods:
AMS Intercooler and hard pipes
AMS CAI
AMS DownPipe
HKS SSQV4 BOV VTA
Tomei CatBack Exhaust
greddy profec B spec 2 Manual Boost Controller
at that time the car was boosting 14PSI only so i figured the MBC was set to this. My plane was to ditch the MBC and reconnect the original Solenoid, and i did. and put an OTS map from Cobb (Stage 1 v403 +sf 91OCT (Normal Wastegate)). the boost didn't go up. at 3000rpm reaches 14PSI but above 5000RPM around 12-13 PSI. the car Idles at around -9.9 PSI
so i started simple and went to a shop the "supposedly" specializes in Evos and performed a boost leak test, he took the cone filter out and put his fitting and pressurized the system, no leaks where found. on my way back i did a pull on 3rd gear, and just after it the Service engine soon light came on, i pulled the code and its p0171 (lean system).
the car doesn't hesitate or act, just not powerful enough on high rpms.
what im thinking now is:
faulty boost solenoid
bad wastegate/rod/turbo
exhaust leak on the exhaust manifold
bad CAT, although its the stock one, im thinking this because the BOV is VTA so i figured lots of unburned fuel goes there is ruin it.
ur opinions and help would be much appreciated.
Thanks.
2011 Evo X GSR USDM.
Last edited by khaled_hourani; Apr 11, 2017 at 05:34 AM.
Apr 11, 2017, 07:41 AM
#2
If you're leaning out I definitely wouldn't be driving unless you have $8k laying around for an engine!
Get rid of the MBC, use either the factory setup or use an EBCS. Also, do you have a Wideband gauge? I'd like to see what your AFR was during WOT. I keep forgetting whether or not the 2011 has the revised fuel relay but thats something I'd check out too. When the shop did the boost leak test did they say what they tested up to? If the tune is supposed to run at say 25psi, you'd have to pressurize to 25 to see if theres any leaks (a lot of people are afraid to do the boost leak test so they only pressurize to 5-10psi).
Any vacuum leaks? Even a small leak can cause the issues you're seeing. From my own experience a vacuum line popped off wreaking havoc on all of my gauges and such.
Get rid of the MBC, use either the factory setup or use an EBCS. Also, do you have a Wideband gauge? I'd like to see what your AFR was during WOT. I keep forgetting whether or not the 2011 has the revised fuel relay but thats something I'd check out too. When the shop did the boost leak test did they say what they tested up to? If the tune is supposed to run at say 25psi, you'd have to pressurize to 25 to see if theres any leaks (a lot of people are afraid to do the boost leak test so they only pressurize to 5-10psi).
Any vacuum leaks? Even a small leak can cause the issues you're seeing. From my own experience a vacuum line popped off wreaking havoc on all of my gauges and such.
Apr 11, 2017, 08:20 AM
#3
Newbie
Thread Starter
If you're leaning out I definitely wouldn't be driving unless you have $8k laying around for an engine!
Get rid of the MBC, use either the factory setup or use an EBCS. Also, do you have a Wideband gauge? I'd like to see what your AFR was during WOT. I keep forgetting whether or not the 2011 has the revised fuel relay but thats something I'd check out too. When the shop did the boost leak test did they say what they tested up to? If the tune is supposed to run at say 25psi, you'd have to pressurize to 25 to see if theres any leaks (a lot of people are afraid to do the boost leak test so they only pressurize to 5-10psi).
Any vacuum leaks? Even a small leak can cause the issues you're seeing. From my own experience a vacuum line popped off wreaking havoc on all of my gauges and such.
Get rid of the MBC, use either the factory setup or use an EBCS. Also, do you have a Wideband gauge? I'd like to see what your AFR was during WOT. I keep forgetting whether or not the 2011 has the revised fuel relay but thats something I'd check out too. When the shop did the boost leak test did they say what they tested up to? If the tune is supposed to run at say 25psi, you'd have to pressurize to 25 to see if theres any leaks (a lot of people are afraid to do the boost leak test so they only pressurize to 5-10psi).
Any vacuum leaks? Even a small leak can cause the issues you're seeing. From my own experience a vacuum line popped off wreaking havoc on all of my gauges and such.
I did get rid of the MBC, im now in the stock solenoid and still no proper boost. The guy didnt say what pressure he used. I do not have a wideband gauge but i can provide u with a log from the AP, would that help?
and i cant understand y would it run lean and also low on boost, it should rum rich. Anyways today the p0171 code went away by it self.
Apr 11, 2017, 08:30 AM
#4
Theres a bunch of reasons why it would run lean and low boost. A vacuum leak being one of them. You can post a log, but if I were you I'd get a wideband gauge ASAP. That thing can save your ***!
Is the car sputtering or anything? Have you checked the spark plugs to make sure they're in good condition? In terms of the bov do you have the oem one by any chance? I wonder if the one you have in now isn't set correctly.
Definitely triple check all of your vacuum wiring and with the car running at idle see what the AP is saying your vacuum/boost is at.
Is the car sputtering or anything? Have you checked the spark plugs to make sure they're in good condition? In terms of the bov do you have the oem one by any chance? I wonder if the one you have in now isn't set correctly.
Definitely triple check all of your vacuum wiring and with the car running at idle see what the AP is saying your vacuum/boost is at.
Apr 11, 2017, 08:52 AM
#5
Newbie
Thread Starter
Theres a bunch of reasons why it would run lean and low boost. A vacuum leak being one of them. You can post a log, but if I were you I'd get a wideband gauge ASAP. That thing can save your ***!
Is the car sputtering or anything? Have you checked the spark plugs to make sure they're in good condition? In terms of the bov do you have the oem one by any chance? I wonder if the one you have in now isn't set correctly.
Definitely triple check all of your vacuum wiring and with the car running at idle see what the AP is saying your vacuum/boost is at.
Is the car sputtering or anything? Have you checked the spark plugs to make sure they're in good condition? In terms of the bov do you have the oem one by any chance? I wonder if the one you have in now isn't set correctly.
Definitely triple check all of your vacuum wiring and with the car running at idle see what the AP is saying your vacuum/boost is at.
Im will order a wideband gauge ASAP. the car runs very fine no hesitation or sputtering or anything except that its not very powerful on high rpm. I will definitely check my sparks and vacuum hoses again. The bov is the HKS SSQV4 and is set to VTA
. It's definitely not leaking boost i checked. But set correctly?! I have no idea. I already ordered the recirculation kit just waiting for it to arrive. And my AP says i idle at -9.5~ PSI
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khaled_hourani (Apr 11, 2017)
Apr 11, 2017, 12:52 PM
#10
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Thread Starter
Dude, if what u r sayin is true that is a GREAT tip. Indeed i am not using oem hoses, just some vacuum hoses and Ts from a parts store. If i get a grimmspeed EBCS would i need this boost pill? Do u think i should do it?
Apr 11, 2017, 01:27 PM
#12
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Apr 11, 2017, 01:37 PM
#14
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