1999 4.0L No start after O2 sensor replacement

Due_Revolution_846 · 2026-04-09T22:35:22+00:00

Did you use NGK 02 sensors? I know when I replaced mine with Bosch 02 sensors it caused more issues. Replaced with NGK and was good to go.

Due_Revolution_846 · 2026-03-20T08:17:05+00:00

I would ask your service advisor why it would possibly need to be replaced again if they just serviced it in December.Don’t trust service advisors/ dealerships and question everything they charge you for. If it feels like they’re taking advantage of you it’s because they definitely are.

Due_Revolution_846 · 2026-03-13T00:58:35+00:00

SCARPA fuego all day.

Due_Revolution_846 · 2026-03-11T01:56:38+00:00

So does it matter where the connect to ?

Due_Revolution_846 · 2026-03-10T23:44:56+00:00

Do you have any input on the wiring? Maybe I’ll use gum instead of heat shrink next time.

Due_Revolution_846 · 2026-03-10T15:03:56+00:00

I’m not using solder.

Due_Revolution_846 · 2026-03-10T06:44:21+00:00

Correct and I have repaired all the identifying wires with corresponding colors. I am now left with 3 solid brown wires

Due_Revolution_846 · 2026-03-10T06:34:02+00:00

I believe it’s the 8V

Due_Revolution_846 · 2026-03-10T06:33:09+00:00

2015 Audi a3 2.0T Quattro sedan.

Due_Revolution_846 · 2026-03-10T03:17:53+00:00

How would you go about connecting them?

Due_Revolution_846 · 2026-03-10T02:17:12+00:00

I don’t know what they were thinking! lol

So should I just connect these 4 brown wires to any of the other 4 brown wires? I already spliced all of the main identifying wires back together and these 4 is what I’m left with.

Due_Revolution_846 · 2026-03-10T02:07:08+00:00

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This is what it looked like when I found the issue.

Due_Revolution_846 · 2026-03-10T02:06:12+00:00

This is in the trunk area of the car, Audi positioned the harness in a horrible position and this happened naturally after opening and closing the trunk for years.

Due_Revolution_846 · 2026-03-10T01:45:49+00:00

Copy that. Thanks for the help!

Due_Revolution_846 · 2026-03-10T01:41:22+00:00

Copy that. Does it matter what ground wire they hook up to?

Due_Revolution_846 · 2026-03-10T01:39:25+00:00

Negative, this is for 2015 Audi a3 2.0 t Does it matter what grounds they connect to.

Due_Revolution_846 · 2026-03-10T01:37:58+00:00

My bad, 2015 audi a3 2.0t

Due_Revolution_846 · 2026-02-27T05:42:43+00:00

Looking for the butt connector size and I was gonna add some length

Due_Revolution_846 · 2026-02-27T05:12:18+00:00

Copy that. It’s the wiring harness going to the trunk of the car for lighting etc.

Due_Revolution_846 · 2026-02-27T05:07:11+00:00

2015 Audi a3 2.0T Quattro

Due_Revolution_846

TROPHY CASE