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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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new engine's running now it's time to tune

  • Thread starter Thread starter rj95svt
  • Start date Start date Jun 24, 2008

rj95svt

Member
Jan 11, 2007
422
0
16
Hayden, AL
Jun 24, 2008
#1
  • Jun 24, 2008
  • #1
I have just got my new engine running last weekend and I'm having a small problem (some things were expected). I have never done any major tuning as I had a mostly stock car. I am still running a stock maf, TB, heads(lightly ported), intake, and stock 24lb injectors. I am however running a crower 15511 cam, mac 1 5/8 shorties, CAI, and O/R x pipe. All of this is on a stock j4j1 tune with the smog and egr turned off and some minor tweaks to the timing tables as of right now.

The problem is a lean condition which is triggering a CEL for both banks running lean O2's not switching. The car will go into closed loop for several seconds and the O2's will read .512-.537. The lambse's will go all the way down to 10.92 and the car will almost die when it does this if it's idling. The Kam's will never become active. The car will go back into open loop and not switch back to closed loop again. The O2's are new and read exactly the same as the old ones did. I have checked for vaccum leaks and have found none. I need to get a vaccum gauge to check to see how much vaccum it has.

I have got EA downloaded but I haven't got it registered yet it will be Friday before I can do it as I've spent all my money getting the car running. Where do I need to start to get everything right? I know there is gonna be a steep learning curve doing all this and forgive me if I've missed something that needs to be done or didn't give all the information needed.

Thanks in advance, Jarad
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Jun 24, 2008
#2
  • Jun 24, 2008
  • #2
Post up a log and your tune, unless something in the tune is wack, you should not be having those problems, likely a mechanical type problem.

Wes
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Jun 24, 2008
#3
  • Jun 24, 2008
  • #3
Be sure to check for any exhaust leaks around those O2s and also around your CAI couplers.

Wes
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jun 24, 2008
#4
  • Jun 24, 2008
  • #4
I'm with Mr. Wes

Most likely something small you've over looked

Those mods should not throw things off ... THAT ... much

Just go over everything again and pay attention to detail

Grady
 

rj95svt

Member
Jan 11, 2007
422
0
16
Hayden, AL
Jun 25, 2008
#5
  • Jun 25, 2008
  • #5
That's what I thought originally until I couldn't find any vaccum leak but with you guys saying that I'm gonna go through and check everything again. The tune is the same one I was running before without these problems with no changes at all.

I will double check everything thoroughly. It will probably be this weekend before I can check everything but I'll post up what I find.

I am unsure how to post a datalog or I would.

Thanks guys
 

rj95svt

Member
Jan 11, 2007
422
0
16
Hayden, AL
Jun 30, 2008
#6
  • Jun 30, 2008
  • #6
Well guys I've checked and double checked for vaccum leaks with no luck. I'm gonna get vaccum gauge as I still suspect a vaccum leak but using carb cleaner spraying around all the components I've noticed no changes. I'm beginning to wonder if the lower intake is sealed up good underneath. I am gonna try to borrow a vaccum gauge this afternoon to see if I can find anything.
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Jun 30, 2008
#7
  • Jun 30, 2008
  • #7
I'll PM you my email and you can send me your log/tune and I'll go through it and look for anything screwy.

Wes
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jun 30, 2008
#8
  • Jun 30, 2008
  • #8
rj95svt said:
Well guys I've checked and double checked for vaccum leaks with no luck. I'm gonna get vaccum gauge as I still suspect a vaccum leak but using carb cleaner spraying around all the components I've noticed no changes. I'm beginning to wonder if the lower intake is sealed up good underneath. I am gonna try to borrow a vaccum gauge this afternoon to see if I can find anything.
Click to expand...

If you suspect the lower might not be sealing
why not check all the lower bolts to see if any might have loosened

Its not all that uncommon
for a few of them to be loose after a couple of heat cycles have passed

Good Luck

Grady
 

rj95svt

Member
Jan 11, 2007
422
0
16
Hayden, AL
Jul 1, 2008
#9
  • Jul 1, 2008
  • #9
Well guys I found my problem yesterday when I was changing the oil. The plug on the driver side of the balancer that apparantly connects the O2's to the computer harness was unplugged. I plugged it in and no more check engine light and the O2's are swithching like normal. I felt like a complete idiot. It is still running on the lean side as the kam's were getting into the 1.15-1.18 range.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jul 1, 2008
#10
  • Jul 1, 2008
  • #10
rj95svt said:
Well guys I found my problem yesterday when I was changing the oil. The plug on the driver side of the balancer that apparantly connects the O2's to the computer harness was unplugged. I plugged it in and no more check engine light and the O2's are swithching like normal. I felt like a complete idiot. It is still running on the lean side as the kam's were getting into the 1.15-1.18 range.
Click to expand...


See there

Its usually something really simple
that can cause you so much grief

Good to see you are now able to move on and make some progress

Grady
 

rj95svt

Member
Jan 11, 2007
422
0
16
Hayden, AL
Jul 3, 2008
#11
  • Jul 3, 2008
  • #11
Yes I figured it was gonna be but I didn't think it was gonna be that simple. The car is running better now than it was. It seems the major bugs are worked out. I haven't bought EA yet but I plan to do so soon.

I am really quiet happy with the way the car seems to be running as it is. After I fixed the CEL issue the car hasn't stalled at idle once or anything. The engine idles smoothly at 750rpm's and doesn't search or hang at a high idle. The car does buck a small amount but only when idling in first below 1,000 rpms. I am really not expecting to make great driveability improvements but I think some inprovement can be made.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jul 3, 2008
#12
  • Jul 3, 2008
  • #12
rj95svt said:
I am really not expecting to make great driveability improvements but I think some inprovement can be made.
Click to expand...

Respectively

I just gotta tell you

I have to believe you have not set your goal high enough

I am certain :Word:
That combo can be made to behave like a little stocker Stang
in every way
except
for a bit of cam lope

You just gotta be willing to ... tweec ... things a bit
and of course ...
Do a bit of research to find out what adjustments can help stabilize things

Allow me to share a tip or two about drivability from my findings

Bucking during cruising can be helped or eleminated by reducing spark
at light loads in the spark tables.

I found idle and light load conditions seemed to be more tame with a bit
more rich mixture.

The injector timing can make a difference on drivability ... big time.

Throttle body airflow and neutral idle airflow (I think that is what its called )
can make a differnece as well.

If you try and idle down too low .....
You can go around and around in circles
cause
The tune at idle just won't stabilize

Now on that last tip ................

Its something I learned the hard way
and
I suspect it has a lot to do with the fact .........
I got a cam with a very narrow lsa
so
You might not have any issues or probs with that

But ... I did

Grady
 

rj95svt

Member
Jan 11, 2007
422
0
16
Hayden, AL
Jul 7, 2008
#13
  • Jul 7, 2008
  • #13
I have a wide lsa cam (114). I know inprovements can be made and after I have driven it more I have started to notice some more small things that could be helped with tuning. I haven't done any tuning yet as I've wanted to get EA before making many changes. I think I'll get better results being my first time doing this if I have EA.

I planned on getting EA last week but I have got to pay a ticket for having illegal window tint. I didn't know it was illegal till I got pulled over because the car was bought this way.
 

Methodical

15 Year Member
Dec 1, 2003
1,192
11
59
Clinton, MD
Aug 28, 2008
#14
  • Aug 28, 2008
  • #14
RJ hows it going? What tuning have you've done and how has it worked out. Just checking up on ya.
 
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