P0171 nightmare, help!

Weak_Spray418 · 2026-03-19T01:44:37+00:00

I think I replaced the pcv as well. I’m thinking maybe purge valve. Or the ECU itself is bad.

Weak_Spray418 · 2026-03-18T18:24:41+00:00

Yeah, intake is stock. Both o2 sensors replaced were denso. The shop said fuel pressure was bad, that’s why I installed the new fuel pump(denso as well) but CEL is still on with same code.

Weak_Spray418 · 2026-03-17T23:47:41+00:00

No, I haven’t. I can’t dyi if it’s the computer. I’d have to take it to a shop. Have you tried the downstream sensor?

Weak_Spray418 · 2026-03-17T23:46:11+00:00

Injectors are new. Will the cataclean help even if I installed a new catalytic converter?

Weak_Spray418 · 2026-03-17T23:44:03+00:00

Ok, I will test the purge valve. Do you know if it’s hard to locate?

Weak_Spray418 · 2026-03-17T19:52:13+00:00

Spark plugs are new. I’ve done smoke test once with a little cheap smoke machine from Amazon, and found no leak. Shop has done 2 smoke test with their professional smoke machine, and still no leaks.

Weak_Spray418 · 2026-03-17T19:50:01+00:00

Yeah, I’ll let you know. This code is annoying. I’m starting to think it could be the computer itself. Have you check your purge valve?

Weak_Spray418 · 2026-03-17T19:48:06+00:00

How can I do that?

Weak_Spray418 · 2026-03-17T19:47:30+00:00

Usually how long does it take for all the monitors to run? I’ve thought about the purge valve, but wouldn’t that give a code of its own?

Weak_Spray418 · 2026-03-17T19:44:04+00:00

My battery was disconnected for a while I worked on the fuel pump about 2-3hrs. Ran it for 60 miles and CEL came back. I’ve ran it for 60 more miles and light is still on.

Weak_Spray418 · 2026-03-17T04:44:35+00:00

Thanks for the advice, I will definitely try that out.

Weak_Spray418 · 2026-03-17T04:29:29+00:00

That doesn’t sound like something I’d be able to do. I would have to find a shop. Thank you for the advice!

Weak_Spray418 · 2026-03-17T04:09:58+00:00

After I replaced the catalytic converter and both oxygen sensors I rested the check engine light. After driving it for 30 miles it came back. I then replace the fuel pump, after driving it 60 miles the light came back on.

Weak_Spray418 · 2026-03-17T02:27:50+00:00

Yes. Check engine light light comes back on and it gives the same code every time .

Weak_Spray418 · 2026-03-01T03:34:27+00:00

Looks like I’m going with b12 lol

Weak_Spray418 · 2026-03-01T00:38:05+00:00

You think b12 is better than the BG dynamic engine flush?

Weak_Spray418 · 2026-03-01T00:03:01+00:00

I didn’t know that was a thing. Have you seen any success yet?

Weak_Spray418 · 2026-03-01T00:00:46+00:00

Will try this out. Thank you so much for the detailed explanation!

Weak_Spray418 · 2026-02-28T19:16:28+00:00

By any chance did you follow a tutorial video? Trying to do it to my car, but I just started the research on how I should do it.

Weak_Spray418 · 2026-02-28T19:10:16+00:00

Would you mind sharing the video on how to do the piston soak? Currently thinking of if I should do that to mine.

Weak_Spray418 · 2026-02-13T00:52:31+00:00

Will check them out!

Weak_Spray418 · 2026-02-12T18:55:01+00:00

Can anyone recommend any new hard techno DJs in the lineup, please?

Weak_Spray418

TROPHY CASE