[cubano]

Hey everyone I am new to the scooby family just bought an 02 WRX and loving it but I am having an issue with it, a few days ago I popped a p0171 code and after hearing the spudder I changed out the A/F ratio sensor which solved the problem and the engine code went away but heres the thing I was also having issues with a hesitation once I got up to about 4500rpm 1/2 throttle and on top of that I am not getting full boost when I do go WOT it still hesitates and still only at 7psi. I thought it could have something to do with the tune from a cobb accessport version 1 its a stage 2 tune that the guy i bought it off of put on it. I accidentally forgot to reconnect the MAS to the ecu once i put it back in and it ran smoother without the hesitation. This has me baffled as far as the hesitation is concerned , why is it running smoother without the MAS then it is with. Any help wouod be great thanks.

 

[subaken]

Hey everyone I am new to the scooby family just bought an 02 WRX and loving it but I am having an issue with it, a few days ago I popped a p0171 code and after hearing the spudder I changed out the A/F ratio sensor which solved the problem and the engine code went away but heres the thing I was also having issues with a hesitation once I got up to about 4500rpm 1/2 throttle and on top of that I am not getting full boost when I do go WOT it still hesitates and still only at 7psi. I thought it could have something to do with the tune from a cobb accessport version 1 its a stage 2 tune that the guy i bought it off of put on it. I accidentally forgot to reconnect the MAS to the ecu once i put it back in and it ran smoother without the hesitation. This has me baffled as far as the hesitation is concerned , why is it running smoother without the MAS then it is with. Any help wouod be great thanks.

im guessin it was in limp mode

 

[SD_GR]

When the car runs better without actual air flow data, it could be that those data the car got when the sensor was connected were nonsensical from the ECU's point of view.

Please list any/all modifications on the car to the best of your ability. I am guessing the car has an incorrect intake fitted.

Typically, a PO171 implies an intake problem, a vacuum problem, a boost problem, a metering problem, or a fuel pressure reference problem -- and my guess is that the order given would not be unrealistic compared to the frequency of occurence.

 

[cubano]

It does have an intake k &n, stage 2 tune from the version 1 cobb, prodrive exhuast, grimspeed uppipe, borla headers and thats all that i know.

 

[cubano]

To add to this if it did have a vacuum issue wouldnt it not be able to idle very well? Mine is holding strong at 500rpms idle.

 

[SD_GR]

You cannot measure 500 rpm with the tachometer. The first "line" on the tack is 500 rpm. It is likely your motor is holding at ~750 rpm, and that's normal.

Whether it idles OK won't allow you to exclude a vacuum leak, a boost leak, or an intake problem. Idling bad would imply something like that going wrong, but idling OK doesn't necessarily mean you don't have one of the above issues.

 

[cubano]

Alright cool thanks.

 

[SD_GR]

OK great. If you continue having problems do not hesitate to post back with the full list of modifications and if you have any data logs or symptoms etc. not mentioned, those too.

 

[cubano]

Will do thanks again I will check on what has been mentioned and let yall know.

 

[mycologist]

Do you have the Cobb AP? I was able to log with the cable from that and romraider. That would tell you a lot.

7 psi is wastegate spring pressure. Either your car is so messed up your ECU is not allowing boost, or you have something wrong in the vacuum lines to the turbo/BCS (no restrictor pill, wrong size lines, T fitting). Search google images there is a pic of the stock setup that has been posted a ton. Or far less likely a mechanical issue with the turbo, exhaust, or motor.

Your MAF is installed with the connectors facing forward? Is it clean (search and read the directions carefully - the sensor is a coiled wire up inside, not just the heater bulb.

Any air leaks in the intake tract between the MAF and the turbo? Make sure the clamps are tight etc. or use a boost leak tester (properly, find the directions).

 

[mycologist]

Also, if you used a universal A/F sensor that may be the problem yet.

 

[cubano]

The A/F sensor that I used was a denzo part number 2369011

 

[cubano]

Alright update, on the way home I hooked up the cobb accessport and read the live boost the good news with out the MAS plugged in it was reading 14.1 psi WOT, and at idle it was reading -9.3psi also when i got home it was idling a little high not sure if that was because of some spirited driving. I checked the lines coming fromt he turbo didnt see or feel anything loose but I will check again in the morning when theres light.

 

[EJ257]

It does have an intake k &n, stage 2 tune from the version 1 cobb, prodrive exhuast, grimspeed uppipe, borla headers and thats all that i know.

You mention a Prodrive exhaust (usually, this just means the axleback). Is the stock downpipe on the car?

 

[cubano]

No its an aftermarket one but i dont know who made this one.

 

[Mikie13]

You said that the AP had a Stage 2 map that "the guy you bought it off of put on it"...do you know if it's a base stage 2 map or if it was some sort of a protune? If it's a protune, it might not work the best for your car.

 

[cubano]

I am pretty sure its a base map, he did say he had never had an issue with it till recently and that hes had the map on there for a year. Is there a way to find out if it is a protune or a base for sure.

 

[Mikie13]

I am pretty sure its a base map, he did say he had never had an issue with it till recently and that hes had the map on there for a year. Is there a way to find out if it is a protune or a base for sure.

not sure on the V1 APs...datalog your car? That should tell you...

 

[mycologist]

As said above, the car can probably be logged with the V1 cable and Romraider. You may even be able to save a copy of the map with ECUflash to look directly at the rom (don't think so though). I'd assume a protune would have a different boost target than cobb, or other obvious differences with the timing or fuel targets we could see in the logs.

Also as said above, a log will tell you a lot more than us guessing at things.

http://www.clubwrx.net/forums/tunin...nagement/134322905-datalogging-romraider.html

Regardless, you should be cleaning and checking your MAF and for intake leaks and boost control system leaks at least (we don't call it MAS).

 

[cubano]

Alright so here it is I downloaded romraider and this is the log that i did with the MAF is connected on this see what you guys think
View attachment romraiderlog_20120404_222735 - Sheet 1.pdf

I have a few more if anyone is interested but hte files are too big to put on here.