PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

New mod? = SES..." help"

Thread Tools
 
Search this Thread
 
Old Sep 14, 2013 | 11:13 AM
  #1  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default New mod? = SES..." help"

So since last time at track I added SSRA ram air extension to my SLP ram air, put UMI Lca's on
and I P/P T.B.

Perfect night for racing 40% humidity and upper 50's temp's

So first pass. 13.81@101.2 w/2.06 60'ft
next pass 13.72@ 102.4mph w. 2.15 60'ft

during second pass SES light came on. So I left track knowing something is wrong.
Last time at the track I ran 13.07 and 13.08 back to back hot lapping on a 70% humidity upper 70deg day.

Get home and scan code p0131 02 sensor low volt bank 1 sensor 1
02 reading 0.09-0.11 does this seem correct?????
would this pull timing and make it slow. drove 20 miles home and seem to run fine with plenty of power. I even drove 500 miles to LS Fest with P/P TB with no issues

Did I getting to much air from SSRA lean it out??. Or vacuum leak??
I did not change TB gasket when I removed it. Vacuum line from TB to intake looks good.
Or do I have a bad 02 sensor? What should a good 02 read??

any advise would be very helpful
Thanks "mods in sig"
Reply
Old Sep 14, 2013 | 04:42 PM
  #2  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

Update.
Cleared codes and did some WOT pulls and data log.
P0131 & p0151 showed up. I only had p0131 yesterday. Bank 1& 2 sensor 1
Was reading 0.02- 0.92 02 voltage.
Is it possible port and polish tb can lean out 02's
Im way over my head when it come to tuning
Reply
Old Sep 14, 2013 | 07:23 PM
  #3  
2xLS1's Avatar
TECH Senior Member
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (25)
 
Joined: Nov 2001
Posts: 5,649
Likes: 9
From: Warr Acres, OK
Default

Originally Posted by Red97GT
Update.

Is it possible port and polish tb can lean out 02's
No

What were the O2s mv showing only at WOT. Guessing were you were logging with a Predator. Any way to export the log so it is post-able like maybe in an excel file format?
Reply
Old Sep 14, 2013 | 07:45 PM
  #4  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

2xLS1 i dont have cable to export file.
Looking at log file WOT was 0.04 for both 02's and 0.92 as soon as i let out of throttle.

I replaced TB gasket and vacuum hose from TB to intake and still throws p0131 & p0151. it hasnt thrown a hard fault SESlike yesterday, but when I scan it is there.
only does it when i pull WOT pulls.
What would lean out a 02 sensor 1???
Reply
Old Sep 14, 2013 | 07:57 PM
  #5  
2xLS1's Avatar
TECH Senior Member
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (25)
 
Joined: Nov 2001
Posts: 5,649
Likes: 9
From: Warr Acres, OK
Default

Low fuel pressure, air leak downstream of the MAF, Any air getting into the engine that doesn't go through the MAF sensor. There isn't a vacuum line from the TB to the intake. There is a fresh air hose that runs from the throttle body to the front port on the passenger side valve cover.
Reply
Old Sep 14, 2013 | 08:17 PM
  #6  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

Originally Posted by 2xLS1
Low fuel pressure, air leak downstream of the MAF, Any air getting into the engine that doesn't go through the MAF sensor. There isn't a vacuum line from the TB to the intake. There is a fresh air hose that runs from the throttle body to the front port on the passenger side valve cover.
What should fuel pressure be?? Should I change fuel filter and check pressure?

Will a Diablo read fuel pressure?

OOH I replace a fresh air line. Well that make sense.

I did have a very low tank of fuel when I was at the track. I dont know if i was just freaking out but I could have sworn it sounded like the fuel pump was louder on the way home from track. I didnt notice that today.
Reply
Old Sep 14, 2013 | 08:24 PM
  #7  
2xLS1's Avatar
TECH Senior Member
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (25)
 
Joined: Nov 2001
Posts: 5,649
Likes: 9
From: Warr Acres, OK
Default

FP s/b 58 psi.
Reply
Old Sep 14, 2013 | 08:45 PM
  #8  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

Originally Posted by 2xLS1
FP s/b 58 psi.
Just checked Diablo. It wont read fuel pres.
So is 58psi constant pres.?

So it makes sense if im putting a ton more air into engine (ie p/p tb and ssra) and maf is reading it and trying to adjust fuel trims but pressure is insufficent.

If the MAF was bad it would give a diffrent OBDII code?

Car seems to run fine. I have been beating the **** out of it today and it pulls like crazy. But the 1/4 mile time and SES tells the real truth..
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Sep 15, 2013 | 05:11 PM
  #9  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

Update.
Today I changed fuel filter and put some fuel system cleaner in.
Data log showed 0.03mv @ WOT on both banks 1&2 sensor 1. And throw codes again.
Cleared codes and drove home and drove it normal and not going WOT. checked codes and none were there. So it only throws codes at WOT
Reply
Old Sep 15, 2013 | 08:26 PM
  #10  
2xLS1's Avatar
TECH Senior Member
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (25)
 
Joined: Nov 2001
Posts: 5,649
Likes: 9
From: Warr Acres, OK
Default

You are probably seeing .03v which is 30mv. O2s reading 30mv at WOT is extremely lean. They should be around 900 mv. (.900v) Put a fuel pressure gauge on the rail with a long enough hose to tape it to the windshield and check the FP at WOT. Or you could keep blindly throwing parts at it and keep putting junk in the fuel.
Reply
Old Sep 15, 2013 | 08:42 PM
  #11  
Russ K's Avatar
TECH Resident
20 Year Member
Photogenic
Photoriffic
Liked
iTrader: (1)
 
Joined: Apr 2006
Posts: 811
Likes: 4
From: Regina, Sask
Default

Most likely a bad Maf. Just unplug it and see if the 02's go to 800+ mv @WOT. If they do, then just replace the Maf, if not then test the fuel pressure at WOT.

Russ Kemp
Reply
Old Sep 15, 2013 | 08:44 PM
  #12  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

Will a GM Tech II read fuel pressure?
I work for a car dealership. I willl talk with a couple of techs to see who has a gauge that will hook up to the rail.
I was seeing 0.15v at idle. It would jump all over the place. Highest i saw was 0.89. Does this seem normal?
Reply
Old Sep 15, 2013 | 08:52 PM
  #13  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

I didnt data log maf. If maf is bad would it set of a code to?
What should a good maf be reading while logging?
Reply
Old Sep 15, 2013 | 09:01 PM
  #14  
Russ K's Avatar
TECH Resident
20 Year Member
Photogenic
Photoriffic
Liked
iTrader: (1)
 
Joined: Apr 2006
Posts: 811
Likes: 4
From: Regina, Sask
Default

Originally Posted by Red97GT
I didnt data log maf. If maf is bad would it set of a code to?
What should a good maf be reading while logging?
Seen many bad Mafs that didn't set a Maf code. Maf Hz will be ~3000 at idle to 9500+ at WOT & redline. And the more power the engine makes, the higher Hz.

Russ Kemp
Reply
Old Sep 15, 2013 | 09:34 PM
  #15  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

Just went out and checked 02s at idle with maf pluged in was .15-.09 unpluged it jumped around from.89-.04. Cant go do WOT pulls right now.
I did have maf off when i ported TB
Reply
Old Sep 15, 2013 | 10:34 PM
  #16  
2xLS1's Avatar
TECH Senior Member
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (25)
 
Joined: Nov 2001
Posts: 5,649
Likes: 9
From: Warr Acres, OK
Default

Originally Posted by Red97GT
Will a GM Tech II read fuel pressure?
I work for a car dealership. I willl talk with a couple of techs to see who has a gauge that will hook up to the rail.
I was seeing 0.15v at idle. It would jump all over the place. Highest i saw was 0.89. Does this seem normal?
O2s switch between 100mv and 900mv continuously in closed loop idle and part throttle. That is how they maintain 14.7:1 A/F ratio by going above and below 450mv. There is no FP sensor on a 00 F-body.You have to use a pressure gauge on the rail.
Reply
Old Sep 16, 2013 | 06:29 PM
  #17  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

Update.
Fuel pressure 60 psi at start up. Wot first gear pull. Psi38# 02's drop to .05

Unpluged maf while logging for
Second pull wot 1st thru 2nd gear. 35psi thru 2nd gear
02's start at .87 then drop quick to .06
So fuel pressure is to low. Pump going bad?
Reply
Old Sep 16, 2013 | 07:10 PM
  #18  
Russ K's Avatar
TECH Resident
20 Year Member
Photogenic
Photoriffic
Liked
iTrader: (1)
 
Joined: Apr 2006
Posts: 811
Likes: 4
From: Regina, Sask
Default

Since your fuel filter is new, you need a new fuel pump. The pressure shouldn't go lower than ~54 psi @wot at redline.

Russ Kemp

Last edited by Russ K; Sep 16, 2013 at 07:18 PM.
Reply
Old Sep 16, 2013 | 07:15 PM
  #19  
2xLS1's Avatar
TECH Senior Member
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (25)
 
Joined: Nov 2001
Posts: 5,649
Likes: 9
From: Warr Acres, OK
Default

And if you are going to replace the pump with an OEM style then use only an AC Delco. Stay away from auto parts store off brand pumps especially Airtex.
Reply
Old Sep 16, 2013 | 07:25 PM
  #20  
Red97GT's Avatar
Thread Starter
12 Second Club
 
Joined: Jan 2006
Posts: 54
Likes: 0
Default

Thanks for the help guys.

Sucks I have to do a fuel pump and racing season weather is perfect right now.
I better go shopping and see if I can pick up a pump.
Do I have to drop the tank to put pump in??

Thanks again I will update when pump install happens.
Reply



All times are GMT -5. The time now is 11:03 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE