What is happening in this AFR plot, ideas ?
Thread Starter
Drifting
Joined: Jul 2000
Posts: 1,517
Likes: 1
From: Stockholm
What is happening in this AFR plot, ideas ?
I've installed a FJO Wideband in my car. The sensor is mounted in a 3" H-pipe installed directly after the LT headers but before the cats.
Any ideas what could be happening at 4100rpm ?
I made six runs today in forth gear starting at about 1300rpm and floored it up to 6100rpm, all plots came out the same - engine problem or wideband problem?
[Modified by vette.se, 4:08 PM 11/4/2003]
Any ideas what could be happening at 4100rpm ?
I made six runs today in forth gear starting at about 1300rpm and floored it up to 6100rpm, all plots came out the same - engine problem or wideband problem?
[Modified by vette.se, 4:08 PM 11/4/2003]
Thread Starter
Drifting
Joined: Jul 2000
Posts: 1,517
Likes: 1
From: Stockholm
Re: What is happening in this AFR plot, ideas ? ('97 C5)
97 C5,
I have COT enabled, do you think the cat gets overheated and the PCM tries to cool things down by adding a lot of fuel :confused:
The engine is a 427' so maybe it's to much for the stock cats?
Thanks :cheers:
I have COT enabled, do you think the cat gets overheated and the PCM tries to cool things down by adding a lot of fuel :confused:
The engine is a 427' so maybe it's to much for the stock cats?
Thanks :cheers:
Instructor
Joined: Sep 2003
Posts: 145
Likes: 0
From: Scottsdale Arizona
Re: What is happening in this AFR plot, ideas ? (vette.se)
Check your post at ls1tuning.com. I answered in detail there but the long and short is that your sensor is most likely overheating. You need to install a heat sink between the sensor and the bung. If it were the COT most likely your AFR would gradually richen due to the three or four step up values of over temp protection in the PCM. If you have ls1 edit just change those values to max out each step at 1279* that will still protect your cats but give you some extra cushin for higher temps from mods.
