The P0171 returns...

[YlwMSP]

The last time the P0171 code showed up, it turned out to be a bad battery messing with the SSAFC, and it went away. That was back in January. Today the car randomly had a rough idle, it would drop to around 500 RPM and then shoot up to 1k RPM, but it never stalled. And as soon as it started the CEL came on. Then I checked my boost gauge and it was saying that I'm at -10 psi at idle, and if I get on it at all, I only get 4-5 psi of boost. Does anybody know if it could be the stock bpv going out, since I can hear the turbo spool up, and when I let off the throttle, I can hear fluttering, like the infamous turkey, but since I still have stock intake/intercooler piping, its not as loud as I have seen videos of on youtube. Or if it could be a waste gate problem, or something else completely random. I will try to remember to go out in the day light to check my vac lines from where I tapped into for the SSAFC and the boost gauge and see if they're all still secured.

Thanks in advance for any advice.

 

[Jaleik]

I think its your VTEC that gave up.



I would check for vacuum leaks first.

 

[YlwMSP]

Fixed it. The vacuum line going from the bpv to the intake manifold was cracked and leaking like crazy. I'm kinda surprised that it was even doing its job at all considering how bad the line was.

 

[Jaleik]

Fixed it. The vacuum line going from the bpv to the intake manifold was cracked and leaking like crazy. I'm kinda surprised that it was even doing its job at all considering how bad the line was.

Glad you got that fixed. I would advise replacing all the stock vacuum lines as they are prone to cracking.

 

[YlwMSP]

Well, the code came back again today, and I noticed that i was boosting to around 8 psi...along with some compressor surge as I let off the gas. Could this be a wastegate issue, or the stock bpv shitting out on me? Since the vacuum line coming from the bpv to the intake mani was shot for who knows how long, could it have messed with it?

 

[mazdaspeedp]

I think p0171 is from vacume leak. I had that same code when i was running ssafc and when i removed it the code went away.

 

[YlwMSP]

I think I may have narrowed the leak down today...as I was driving home, I accelerated and all of a sudden, my boost gauge went from normal readings to 0. No vacuum, no boost. But the engine didn't make any different noise, and the idle didnt change at all when I came to a stop. I'll have to check it out in the morning when it's light out.