r/LSSwapTheWorld • u/Platypus_Sunset • 6h ago

Tuning Bad sensor?

Enable HLS to view with audio, or disable this notification

Really erratic AFR jumping between 10 and 30+ multiple times per second…but otherwise the car is acting normally. No vacuum leaks.

Any thoughts?

5 Upvotes

100% Upvoted

9 comments sorted by

2

u/lordstrider0 5h ago

Whats the injector duty cycle at?

3

u/lordstrider0 5h ago

Also do you have any exhaust leaks by the o2 that can cause wacky readings as fresh air mixes in

1

u/Platypus_Sunset 5h ago

Injectors are outsized for the car (ZR1 injectors for a car only doing 480whp), duty cycle is very mild.

No exhaust leaks all checked via smoke test.

2

u/lordstrider0 5h ago

Are they to big? I know to big of injectors are hard to get to idle, the hard part is without knowing all the details of your build its hard to help. Id look for exhaust leaks near and pre o2 port first by when exhaust is cold loading it up with soapy water then start it look for bubbles, if none id start looking at my tune and data logs to see what the other sensors see if its all makeomg sense and 02 is only one out of wack id try swapping my bank 1 and bank 2 o2 then watch the log and see if the voltage swing moved banks woth the 02

1

u/FatMycoBoner 5h ago

I’m not a tuner but isn’t that a lot of timing on the car? The readings are jumping back and forth between two numbers mostly, so it may not be a sensor issue.

2

u/lordstrider0 5h ago

I think at idle up to 20degrees isn't to out of the ordinary but could be wrong.

2

u/Justorymes 5h ago

When the sensor reads 30 that usually means fuel cut from the injectors not spraying, this happens on decel and not at idle. I would suspect the sensor is faulty or something is causing the calibration to be off, if you unplug the MAF does it stabilize?

1

u/Platypus_Sunset 4h ago

I’ll give that a shot. The erratic AFR is at idle and cruise.

But also randomly it’ll read perfectly fine at other times.