Unknown issue, running rough
Thread Starter
Instructor
Joined: Apr 2015
Posts: 207
Likes: 9
Unknown issue, running rough
I was driving one day everything was fine. A week later went to drive and having issues. It is running rough sounds like crap and has a strong fuel smell.
I am modded with stroker motor, cam, etc
So I don't know what is happening. I have 58 psi , I have swapped out maf, map sensor, o2 sensors, drained gas and refilled with additive.
here is a link to a data log for hp tuners.
Any help would be appreciated
https://www.dropbox.com/s/qebk0bga1zpuu96/record-001.aac?dl=0
I am modded with stroker motor, cam, etc
So I don't know what is happening. I have 58 psi , I have swapped out maf, map sensor, o2 sensors, drained gas and refilled with additive.
here is a link to a data log for hp tuners.
Any help would be appreciated
https://www.dropbox.com/s/qebk0bga1zpuu96/record-001.aac?dl=0
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,629
Likes: 4,074
From: Cape Coral, Florida
Couldn't open that file but looking at pages and pages of a data log makes me cross eyed...what do your fuel trims look like at idle and also what is your MAF reading in grams/second ??...should be about the liter displacement of the engine at idle...can you graph O2 sensors with HP Tuners ??...are the upstream O2's switching between 200-800 Mv also at idle ??...if they are "stuck" high or low you may have to look at the O2 wiring.since you changed the sensors...any DTC's ??...whatever air filter you're using when was it last cleaned ??
Thread Starter
Instructor
Joined: Apr 2015
Posts: 207
Likes: 9
I was driving during this. I can do an idle data log. I wonder why you couldn't read it. It's been a little while since my air filter was cleaned. But a week before this happened everything was fine. It's been sitting like this for a couple months and just did this log sunday
Thread Starter
Instructor
Joined: Apr 2015
Posts: 207
Likes: 9
Also I only have the o2 sensors and the collector of the headers the other ones were deleted
I just replaced them after this started because it seemed my others failed.
I just replaced them after this started because it seemed my others failed.
Last edited by MaxximuS; May 12, 2021 at 07:24 PM.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,629
Likes: 4,074
From: Cape Coral, Florida
Just record those numbers...idle MAF grams/second, MAP (KOEO..key on engine off), O2's if they are switching and fuel trims whether positive or negative...dirty air cleaner will make it run rich...we don't have to worry about the downstream O2's !!...also it's a good idea to include in your profile the year of the car and ALL mods !!
Last edited by C5 Diag; May 12, 2021 at 07:30 PM.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,629
Likes: 4,074
From: Cape Coral, Florida
Just key on engine off for MAP and MAF reading at idle in grams/second OR if another value we can always convert it !!...does HP Tuners show MAP in inches of mercury ??
Last edited by C5 Diag; May 12, 2021 at 07:35 PM.
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Drifting
Joined: Apr 2013
Posts: 1,501
Likes: 185
From: Erie PA
I had similar issue and just fixed it last night. turned out being my o2 sensor extension was burned a bit and grounded out. caused a blown fuse that controls the o2 sensors - all o2 sensor codes were on. it was causing severe rich run and then very lean (18.5 afr - 10.5 aft while normal cruising)
fuse #6 in the fuse box under the hood was blown. replaced fuse and fixed wire, all good now.
just something to
fuse #6 in the fuse box under the hood was blown. replaced fuse and fixed wire, all good now.
just something to
Thread Starter
Instructor
Joined: Apr 2015
Posts: 207
Likes: 9
I checked my 02 sensor fuse and it's ok. I have my extensions and o2 sensor wires wrapped in a fiberglass heat wrap. They have melted before. And I have them tiewrapped out of the way so they don't lay in the headers
