bdking57

iTrader: (7)

I just got back from tuning at Gruppe-S and we discovered there is something wrong with my evo somewhere.

My original o2 sensor was damaged back in october during a turbo back install.. i foolishy thought this was a p0420 and just let it be.. turns out it was a p0171,p0134 combo that was causing the car to run mega rich.. although it felt weak it was still alright. We replaced this part today and confirmed that was the problem. The codes are gone. I also recently added a new fuel pressure regulator, walbro 255 and cam gears set at 0,0. I would say after this round of installs the car felt like it needed tuning bad.

the baseline pull came in at 187hp
we tried cam gears at -2-2 with fuel management and the car only put down 201
adjusted back to 0,0 and had a best of 221hp 240tq on91octane.. mustang dyno... seems like the car just falls flat on its face. I will post the dyno chart soon. I was told that im making 20hp less then turbo back cars tuned with the SAFC.

Any ideas to where my problems are? The car has 50K miles.

Our first thought was that the rich condition caused the plugs to become fouled. I picked up new iridium -1 spark plugs.. havent installed yet.

I purchased the car used so im thinking its possible it could have had a flashed ecu.. it did have a MBC when i purchased that was concealed near the turbine. Could a flash be holding me up.. should i go to the dealership and try to get reflashed citing the po300 problem?

The MBC is connected at the BOV line.. i thought their was general consensus that this was the way to do it on the evo but there might be a problem there. I picked up the AVC-R and plan on ripping my mbc out and double checking and recapping all connections.

My last thought is that this is related to the cam gear install... im really hoping this isnt the case.

Helix o2 housing
Helix DP, HFC,
RSR catback
Hallman MBC
Perrin upper IC pipe
AMS lower piping
Fidanza Cam gears (0,0)
adjustable FPR (43.5psi)
walbro 255
S-AFC II

marksae

iTrader: (12)

How much vacuum is your boost gauge reading at idle? If your cam gears were installed off a tooth, your vacuum would read lower than normal (like maybe 11-12 inHg). Your idle would also be rough.

Do you have in intake leak somewhere? If the car falls flat on its' face, you might have a major leak somewhere.

bdking57

iTrader: (7)

I believe its reading - .6 bar at vac.

I have perrin lower ic elbows that are on tight as hell.. the upper pipe is also very tight. Im going to go and tighten all connections. The ams pipe is also on there very securely. Its possible one of the vacumm houses was not plugged properly during the MBC install.

one other possible culprit could be the GFB BOV (two turns from hardest setting). I have it set per the worksrally guidelines but running at full recirculate.

My idle is slightly rough.. but basically the same as other cars.. the exhaust sounds very poppy.. when i let off the gas i feel a stutter at times.. feels like the car suddenly drop in power then picks up again.. or will do this rapidly. It has been doing this for awhile.. since october

bdking57

iTrader: (7)

Im going to check this out as a possible problem, install my AVC-R and install the -1 NGK spark plugs and ill let everyone know the progress.

"I have an 05, had that problem - key word there had - check you bov, yes even the stock dv. its mounted right next to the exhaust manifold. and if you havent felt under the hood after driving - its damn hot. i have my type s in pieces right here in front of me. it has a rubber diaphram in it, guess what - its melted. i was still running something near 19 and sometimes 20 psi, but i always had to tighten it down every week or so, inconsistant boost levels everytime, and i was getting that hicup. i was thinking bad plugs, too rich...took off the bov just to see if it was dirty or jamming - noticed black flakes inside. so i took it off the car, played with the valve, still moved but it didnt feel smooth, took off the hat and bam - diaphram had melted in a few spots letting air in and out - boost leak. this leak caused a over rich mixture, and was giving me the hicup, even though i was close to stock boost it was over compensating for the fuel. stock dv's are abs plastic, but they may not like the high heat either and could also have something similar in warping or melting causing a leak and that hesitation. so check out your bov's or dv(if stock). im going to get the replacement diaphram and redo the hoses so that i can still recir but move it away from the heat source, this will take me a week or so to get the new piece in, but i will surely post the results...and if i can take some pictures of it redone. Here are some of the melted piece and areas that had melted through. Notice the asymmetry of the diaphram when I have it in its normal position, I had to pry it out when I took it apart."

bdking57

iTrader: (7)

I just went for a ride to try and confirm some sort of boost leak.. i thought the whistle GFB bov had opened a notch, but it was on full closed, and i was hearing a whippssttttt sound in second when getting off the gas. I dont know if that the valve recirculating or im leaking somewhere. The funny thing is that i seem to be hitting 1.5 bar no problem so its not like im deficient on boost .. the car just doesnt want to make any power up top.

marksae

iTrader: (12)

Perhaps you can try swapping the stock DV back on to see if the problem goes away. This should help narrow down the culprit.

bdking57

iTrader: (7)

you got it.. thanks for the advice. We are going to try switching back tommorow.

bdking57

iTrader: (7)

I changed the plugs and that seemed to make a big difference... will post pictures of the plugs. There was very little hestitation but the car was still a little stall prone. I put the stock diverter valve in and the car is super smooth though.. although i lost about 1.5 psi of boost switching back. I havent messed with the mbc setup but i intend on redoing all of that. Then i found something else out. I was told the fuel pressure was lowered back down to stock setting.. when i checked it out the car was idling at 43.5 with vacumm.. it should be at 43.5 without vacumm. so the baseline fuel pressure was set at like 52psi!~ If im rising 1:1 from 52psi with boost this sound like its just way to much fuel at higher rpms.


this was the best of the plugs.. the rest had black tips
[img] [/img]

KILTERMAN

iTrader: (9)

Talked to My Mechanic ( which happend to be my mommy) and she seems to think that you are running WAY WAY WAY too rich. she says your prolly dumping to much fuel up top and all its doing is burning and not making power. hope this helps .

BTW , she said she could be wrong

bdking57

iTrader: (7)

haha.. well i talked to some other peps and they to believe the fuel pressure is way to high and is causing a mega rich fuel condition up top. The car is running way leaner then it was before and leans out to 11.3 at 1.5 bar. but somethings up.

03BREvo8

why are you using cam gears with the stock cams.?...

marksae

iTrader: (12)

The wrong base fuel pressure sounds like the culprit. That'll throw your fuel trims way off and make your car run like a$$. It probably caused your plugs to foul.

mooreboost

iTrader: (6)

Did the ECU throw the check engine light for the p0171 and p0134 codes?

And I thought the ECU only gathered info from the o2 sensor at idle?

bdking57

iTrader: (7)

I instaleld a new 02 sensor.. that was also broken. I belive the plugs fouled out because the 02 sensor was not functioning.. thus assuming it was lean it was dumping fuel in. The fuel is much better now and at idle im running a similiar fuel pressure to a car with a walbro 255.. since that pump overuns the fpr to 52 psi at 0 boost.. but then it doesnt keep adding more fuel because it its still actually rising from 43.5 up.


I belive the 02 sensor gathers data when cruising on the high way.. it has something to do with long term fuel trims? anyway.. it would only throw that cell combo on the highway.

bdking57

iTrader: (7)

I dont know why people act like this is such an anomally.. i planned on going vishnu stage one.. which requires adjustable cam gears. I decided not to becuase the distance is to far and i love the way they treat the local cars at gruppe-s. They have been reset to 0,0.. but at least they are in place for when i add cams.