Car info
2011 GSR
AMS short ram intake
TurboSmart Dual Port BOV(fully recirculate)
MAP UICP
Cobb AP
Cobb 3-port EBCS
DW 65c
ETS test pipe
ETS V2 quiet
FIC 1100’s
E85
New relays
AEM uego

Ok so about three months ago I had my car dyno tuned. At the time of the tune they drained my tank and filled it with e85, installed FIC 1100’s, and new spark plugs. My car made 360whp and 360wtq on a dynojet. Since I needed a tune for the new injectors and e85 I had to let them install injectors and drain my tank. So total price out the door for labor and tune was a little under $1,000, which was more than they quoted me. I didn’t really notice a big difference in power compared to Cobb ots maps, but as long as the tune was safe and my car ran fine I was happy.

About a month after my tune I noticed that my LTFT were maxed out at +12.5% and was running really lean. I was getting P0171 code system too lean code and one day I got P0137. So I called up my tuner to let him know what was going on he said to bring it back in. Well the next opening was three weeks away. So I didn’t really have a choice but to wait. The shop told me that if it was tune they would cover the cost but if it was anything mechanical (e.i. boost leak) I would have to pay.


So I swapped out relays and did a boost leak test and found nothing. My car was still running lean. I still thinking it's tune related. Possibly he didn’t scale the maf or the injectors right.

My three weeks were up so I make the 1:45 hour trip back to the tuner. My appointment was at 4:00 tuner didn’t show up until 5:00. He starts to dial in the A/F ratios and comes out and tells me the car is running dangerously lean…. I’m thinking no **** idiot. He tells me there is a mechanical issue causing this. He claims it’s the fuel pump. I told him I put it in about two month before the tune. He continues to tell me that all DW pumps need to be hotwired. I have never heard of anyone having hot wire a DW pump for the stock turbo.


So the tuner and I go to the service writer and inform him of the issue and they recommend I make another appointment to hook up a fuel pressure gauge while on the dyno to see if it’s the fuel pump for sure.

I’m think WTF why not do it right now it only takes five minutes to hook up the fuel pressure gauge.I tell him could it be the tune also…..he says no nothing about the tune has changed ….ummm no **** but it could have bad scaling since the beginning… he says it has to be something mechanical like the fuel pump. So my fuel pump died within a month???



I’m pissed off so I buy the hotwire kit for the fuel pump and pay for the hour of dyno tune service for a total of $200. The tuner did add a bunch of more fuel to get me by.

I take out the fuel pump and everything is connected right and seems to be fine. I take my car to my buddies shop to hook the fuel pressure gauge and at idle it sits at 52psi. I can’t drive around with the gauge taped to windshield because the hose wasn’t long enough. He tells me that dying pump usually have trouble holding psi at idle and are have low psi, he doesn’t think my pump is dying.
I’m thinking it just a ****ty tune the whole time.

I googled the codes P0171 and P0137 and led me to MAF problems. I hadn’t looked into the MAF sensor yet. I didn’t think it could go bad yet the car only has 13K on it.

I check with the MAF with my AP. The maf g/s are maxed out 255g/s during a third gear pull. The volts are also maxed out at 4.4 volts. They are both maxed out by 4000 rpms and just stay at 255g/s and 4.4 volts.



I think I may have found the problem maybe. I ordered a new MAF sensor and put it in on Saturday and go out for a test drive. WTF still maxed out 255g/s and 4.4 volts.

I recall the Cobb OTS maps for AMS intake have the maf scaled to a max of 5 volts at 468.08 g/s.



So is this my problem, just a ****ty tune from the start? Sorry for the long post, besides a bad tune I’m out of ideas any help would be appreciated.

 

Come on guy, any help would be appreciated.

 

I know it can be frustrating the forum can take some time. All I can be of assistance with this problem is a free bumb

 

Is it a reputable tuner?

 

Free Bump,

so the FPR hose is zip tied and has no cracks correct?
and The fuel pump relay is working fine also,
if this is the case then I am unable to provide help or suggestions
sorry,
Maybe call another reputable shop?
Good luck.

 

I took my car to MAP. I heard some good things about MAP and since they make quality parts for the Evo's I figured I could trust them.

 

Yes sir, hoses are zip tied and relays are good. I'm thinking I might just have to have someone else tune it. I just hate to spend more money on a tune, since I'm already in to MAP for $1,200.

 

You don't have an aftermarket DP do you? I had P0171 issue with my speed 3 prior to getting the Evo, took it to CP-E performance and got charged through the *** to have their head tuner look at it and tell me my "Timing is off somehow" ...ended up ****ing being the DP was loose and had a major exhaust leak...sometimes these pro's don't know how to find the easy stuff.

 

^^^^
I don't have a down pipe, but I will make sure the whole exhaust is secure.

I guess my main question is since my maf is maxed out at 255g/s and 4.4 votls would this only be caused by the tune or is there anything else that could cause this? That's almost half the g/s of air flow cobb ams intake map had. So the ecu is only be told half of the actual air flow. This would cause for my lean conditions.

 

I'm pretty sure MAP is perfectly capable of tuning your car properly. I would say its likely not the tune but I can't be certain since I can't see it. Your car doesn't run good for the first month and then all the sudden run like ****. A bad tune would have shown the minute you left or at most hours later.

 

I agree but I have read where it could take a while for the maf to show bad scaling, not sure why though. I just don't know what would cause the maf only to read 255g/s and 4.4 votls besides the tune. I'm open for ideas.

 

DW 65 pump NOT need to be hotwired.
have you check the λ sensor ? a faulty reading can throw you to a faulty Ecu mapping.
Is it tuned correctly for E85 ?

 

Fuel filter?

 

could be mechanical.
could be tune. if you can access your tune, post up your injector scaling and latencies.

are you setup for dual maps? can you switch from e85 back to 93 to test?

 

Very first thing I would do is open the map on your computer and see what map you have loaded in what slot. On the left hand side there's "Switchable Map 0" and "Switchable Map 1". Default is Map 0. If you have a gas tune loaded in the tune for Map 0, but have E85 in your tank, you will run lean for sure.


MAF voltage will usually indicate a dead MAF by reading "0" volts all the time


Since it's MAPerformance, and not some shady tuner, I'm inclined to think its either mechanical, or on the wrong map slot.