Help needed with intake manifold hose

Hi!

Today I was checking oil level and suddenly saw unplugged hose near the intake manifold nipple..

I pluged it back and put zip tie on it.

I really can't say how long I was riding with unplugged hose, but there was no CEL or some weird noises, and I think there was no perfomance issues..

 

Later I was going to my friend , all was ok , but when I floor the gas my car behavior was really strange, first there was no boost, then was flashing CEL for about 2 sec, then it seems like the turbo switched off and the car was like NA without any turbo..

I switched off ignition, then try again, the car was like before, no boost.

Then I unplugged that hose again, didn't help at all..

I was thinking about some turbo or BCS issue..

Then after 5 miles or so, turbo switched on again and it feels like nothing happened..

Later I plug that hose again because those nipple from intake manifold was sucking air from engine bay and there was no issues at all..

I was trying to check that CEL code, but LV was clear, no stored errors, nothing..

 

I'v got some questions.

1) what is that hose for

2) what CEL it could be and why it switched boost off completely

 

I have some photos of that hose and location on intake manifold.

That hose is with green zip tie and it goes to box at the right side of the second photo..(hose with white paint splash on it)

 

Thanks for answers!

 

yeah dude, thats your fuel pressure regulator vac line, you're gunna want to keep that plugged in at all times or else you'll run lean. keep it plugged in and reset ecu(you didnt mention that anywhere) and try again.

yeah dude, thats your fuel pressure regulator vac line, you're gunna want to keep that plugged in at all times or else you'll run lean. keep it plugged in and reset ecu(you didnt mention that anywhere) and try again.

 

Yep, I reseted Ecu.

No issues was until today, was driving hard,and normal..

Again I floored gas ,was at 40mph,when it was 60mph it stucks at this number and. Really loose power,then CEL was flashing for 2-3 sec,but this time after CEL dissapeared the car came back to normal..

 

Again no stored CEL codes, lv logs are good..

This thing bother me so bad..

What it can be?

Before I plug back that hose there was not anything like this..

I think maybe my last rev of tune was done when hose was unplugged and now there is some mess in the ECU with hose plugged back..

Can you try a previous map ?

Can you try a previous map ?

I can,but I didn't want to mess with maps..

Anyway I didn't look at AF ratios at LV logs,I looked later and there was real mess, all numbers are negative..

I will write Shamar about this,but the question is - can this be problem of tune,or can't?

Shamar said that logs was ok,and he doesn't know what it can be(

Today was flashing CEL again, no codes, this time no boost cut,only stucked for a moment..

I think maybe my cat in uppipe(stock) is dead, could it be like this?

But there are no codes,nothing..

 

Is there a way to check cat without disassembling headers,turbo ,etc? (sounds silly,but maybe)

if there are no codes found when using a scan device, use the self diagnostic white connectors for the 05 and scan through all faults, which include BIU and TCU codes.... they may have caused the CEL. search if you dont know how to do this

if there are no codes found when using a scan device, use the self diagnostic white connectors for the 05 and scan through all faults, which include BIU and TCU codes.... they may have caused the CEL. search if you dont know how to do this

 

Done this already..

Nothing,no codes,tcu and other tests was ok..

This is so bad, something wrong,but can't find what..

 

But I think it's a leak or something with intake or exhaust system,because LV logs always show AF corrections..

Maybe this doesn't matter, but I was checking my old logs and the only CEL codes was:

P1518 - STARTER SWITCH LOW INPUT

P1152 - FRONT 02 SENSOR RANGE/PERF LOW B1 S1

p1153 - FRONT 02 SENSOR RANGE/PERF HIGH B1 S1

 

They were always temp codes and I was always resetting ECU for pull logs , they were only 3 times, but 3 code the same time everytime , last time was about 2,5 months ago..

 

Shamar told me that time, that they are temps , so problems was solved..

 

Can this be the clue?

Or this codes and problems with them couldn't make such car behavior?

Problem solved!

 

It wasn't a leak, it wasn't a turbo, it wasn't o2 sensor..

It was ...tadadadam.. stock uppipe cat.

 

Nobody told about that, because all logs was pointing to o2 sensor or leak.

 

Clogged cat in stock uppipe was broken from its housing, and was moving in uppipe the way he likes..

So the flow was sometimes blocked and limited, and sometimes was rattling noise, that I thought was from loosen heat shield.

 

Cel was from sensor in uppipe, but in stage 2 flash most of the codes was disabled, so no codes was stored.

 

So now no more CELs, no more issues and no more AF corrections in logs:)

 

I was waiting too long to change upppipe..

 

P.S Some pictures of my stock uppipe, you could see how cat moves in uppipe..

 

This is why its a general rule to get the stock up pipe out of the car.

 

Also why 07 and later don't have that cat.

 

I thought tha stage 2 ment you had removed the oem up pipe and gone catless up and have a bigger down pipe.