• Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 V6 Mustang Tech

Help! Runs like crap...

  • Thread starter Thread starter dbspcl
  • Start date Start date Sep 2, 2004
D

dbspcl

New Member
Oct 3, 2003
3
0
0
Los Angeles, CA
Sep 2, 2004
#1
  • Sep 2, 2004
  • #1
I have a 2000 automatic that I put a CAI on several months ago. It ran great and then about a month ago the CEL came on and performance now sucks. It's to the point where if there's a hill on the freeway I can't even get to 50mph. I give it gas, but there's no power at all - it starts pinging and won't speed up. Downhill is no problem. The code its giving is P0411, which is the secondary AIR. It's possible I messed something up when putting in the CAI, but I don't think the AIR pump would cause the performance problem. It's almost like the mixture is not right - when I give it gas, it's getting more air, but not the right amount of fuel, that's what I think is causing the poor performance. It's possible I hosed the IAT sensor or the MAF assembly. Is it possible to check those? By the way, I disconnected the whole harness assembly and ran the car, it ran the same (crappy), and I got more CEL codes (MAF/IAT inputs wrong, etc). Thanks for any help.

Deepak
 

Mustang_02

Member
Jan 26, 2004
113
0
17
Sep 2, 2004
#2
  • Sep 2, 2004
  • #2
I got that error and it was the EGR valve.
 
D

dbspcl

New Member
Oct 3, 2003
3
0
0
Los Angeles, CA
Sep 2, 2004
#3
  • Sep 2, 2004
  • #3
I thought the EGR codes were P0401, P0402 and P0403. Were you getting the 411 code? Was your performance like what I describe? Thanks.
 

Mustang_02

Member
Jan 26, 2004
113
0
17
Sep 2, 2004
#4
  • Sep 2, 2004
  • #4
Bad gas mileage, rough idle were my symptoms.
 

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
Sep 2, 2004
#5
  • Sep 2, 2004
  • #5
mine is doing that now, check fuel pressure. mine is intermittant and only does it every 5 minutes and then runs alright when i turn it off then back on. when it starts running worse, it won't go over 40 over hills and sometimes will not go over them. i checked the psi and at idle i got only 28 and when revved it went to 8 psi and started cutting out. it soundes like a 2 stroke 4 wheeler. i am getting an 02 code for this problem but that is only because the car is running lean because of the faulty pump and i have a crappy idle and very bad fuel mileage
 
S

SpectorV

Founding Member
Sep 3, 2000
1,872
0
36
Florence, Alabama
Sep 2, 2004
#6
  • Sep 2, 2004
  • #6
get the codes ran again and then get a shop that knows stangs to help you
 

Ernad

celibate sans pants
Apr 2, 2004
0
1
0
Grand Rapids, MI
Sep 3, 2004
#7
  • Sep 3, 2004
  • #7
dbspcl said:
... I give it gas, but there's no power at all - it starts pinging and won't speed up. Downhill is no problem...
Click to expand...
Downhilll is no problem Sorry, not tryin' to sound mean, but you have to admit it's funny.
 
D

dbspcl

New Member
Oct 3, 2003
3
0
0
Los Angeles, CA
Sep 28, 2004
#8
  • Sep 28, 2004
  • #8
Okay, turns out the cats were blocked. Anyone know how many are supposed to be on a 2000? I think it's 4, but not sure.

The good news is that the cats are covered under Ford's warranty upto something like 80k miles. The dealer says the oxygen sensors are bad too, wants $400 to replace 2. I'm leaning towards leaving those until smog time, but he says it will make the cats go out again. Does anyone know if that's true?
BTW, I had to take the CAI off, I've heard of many cases where the dealer won't cover cats under warranty because of a CAI installed.
 

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
Sep 28, 2004
#9
  • Sep 28, 2004
  • #9
yes after a while the cats will go bad, they are easy to replace and if you have any wrenching know how at all, you can do them,which sensors are the bad ones. it is a good idea to get a small torch and heat the o2 bung red hot if you can and then get a 7/8 wrench or socket if you cut the lines off, and loosen them with a cheater pipe. go to autozone and check the codes, if any there and they will tell you if you have bad o2 sensors. i ran my car with a stuck open injector(which was what i had last week) for weeks and no cat damage. i also have driven it wil a broken intake bolt that was letting water and unmetered air in the cylinder which made the computer dump more fuel and i was smoking horrible black smoke everywhere and it burned peoples eyes. no cat damage either and that was on the same side as the bad injector.
 

Ernad

celibate sans pants
Apr 2, 2004
0
1
0
Grand Rapids, MI
Sep 28, 2004
#10
  • Sep 28, 2004
  • #10
$400 to replace 2 O2 sensors DAAAAAAAAAAAAMN. I say DIY, shouldn't be too hard.
 
You must log in or register to reply here.

Similar threads

0
'04 V6 running rich excessively on both banks
  • 04DSGVert
  • Oct 26, 2025
  • SN95 V6 Mustang Tech
Replies
2
Views
300
SN95 V6 Mustang Tech Oct 27, 2025
04DSGVert
0
L
95 gt engine vibration
  • lenzgt
  • May 11, 2026
  • 1994 - 1995 Specific Tech
Replies
6
Views
133
1994 - 1995 Specific Tech May 26, 2026
lenzgt
L
M
Engine Unexplainable Exhaust Pop and Gurgle
  • Mrnissen122
  • Feb 14, 2026
  • Fox 5.0 Mustang Tech
Replies
12
Views
468
Fox 5.0 Mustang Tech Feb 18, 2026
Noobz347
J
Help Figuring Motor Choice(Possible future turbo)?
  • jaygee15
  • Dec 14, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
13
Views
473
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jan 3, 2026
Jarhead67
J
SURGING IDLE / NO IDLE CHECKLIST FOR 1999–2004 MUSTANG GT (4.6L 2V) - Work In Progress
  • Noobz347
  • Aug 30, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
810
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 V6 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?