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2000 mustang unknown codes

  • Thread starter Thread starter aleborjas
  • Start date Start date Dec 15, 2006

aleborjas

New Member
Sep 11, 2005
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Dec 15, 2006
#1
  • Dec 15, 2006
  • #1
hi, there is a stang that is geting me off is a 2000 car with 5.0 stroker kit, vortech supercharger(15 pounds), aftercooler, 42 pounds injectors, aeromotive fuel system (rails,regulator,lines), dual pumps, lightning maff, p-51 intake, 278 comp cam's, LT headers, 3" mac catback, diablo custom tune chip and make some things weird in iddle some times it's fine but sometimes tha car starts to go up and down the rpm's and sometimes gets rich and gets like crazy i put on the scanner and i don't know these codes 1- P0102 Mass or volume air flow circ. low imput (what sensor is this?) 2- P0135 O2 sensor heater circ. Bank 1 sensor 1 mal funcion 3- P0155 O2 sensor heater circ. Bank 2 sensor 1 (what is this?) the next 2 codes the scaner sais unknown faults P1409 and P1451

i would realy apreciate the help this thing is gettin me crazy and some times when you hit the peddal to the floor the car just turns off!
 

twogts4us

15 Year Member
Apr 1, 2004
4,188
12
79
Dunedin, FL
Dec 15, 2006
#2
  • Dec 15, 2006
  • #2
You lost me at "hi, there is a stang that is geting me off"
 

aleborjas

New Member
Sep 11, 2005
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Dec 15, 2006
#3
  • Dec 15, 2006
  • #3
because is not mines is my cousin's anyone need help with this!
 
G

GTCharles

New Member
Dec 20, 2005
18
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Portland, OR
Dec 16, 2006
#4
  • Dec 16, 2006
  • #4
This is what all the codes stand for:

P0102 - MASS OR VOLUME AIR FLOW CIRCUIT LOW INPUT
P0135 - HO2S SENSOR CIRCUIT MALFUNCTION (HO2S-11)
P0155 - HO2S SENSOR CIRCUIT MALFUNCTION (HO2S-21)
P1409 - EGR VACUUM REGULATOR SOLENOID CIRCUIT MALFUNCTION
P1451 - EVAPORATIVE EMISSION SYSTEM VENT CONTROL CIRCUIT

So your MAF sensor is getting a funny reading and so is both of your upstream (or precat) O2 sensors. The last 2 are telling you that your egr system is getting a weird reading also. And sense you described what sounds like an idle roll I think the EGR codes would probly be a good place to start.

Long story short I'd start by looking for a disconected or leaking vaccum line on your EGR system.

Plus did you recently install any of those parts or have they all been on there for a while? Because if any of it was recently installed you may want to double check all of it.
 

aleborjas

New Member
Sep 11, 2005
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Dec 16, 2006
#5
  • Dec 16, 2006
  • #5
i build the engine with all the stuff and always i had the problem when i build it i eliminate the EGR does not have vacum lines and the EGR sensor only have the electric conection on thats all! what should i change?
 

sgarlic

Founding Member
Apr 21, 2001
3,085
1
56
Dec 16, 2006
#6
  • Dec 16, 2006
  • #6
Too many mods to troubleshoot o2 sensor/maf problems. Gunna have to figure that out yourself since you know the setup, and we don't. Could be the tune, could be an exhaust leak, could be bad o2 sensors, a dirty maf, who the heck knows.
 

aleborjas

New Member
Sep 11, 2005
610
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Dec 17, 2006
#7
  • Dec 17, 2006
  • #7
hi, i've tried an other maff new same 90mm, tried an other chip from an other car with almost same engine, i'm going to put the EGR sensor new both the one that uses vac lines and is electric and the other one that uses tow hoses from the exhaust tube that comes from the header!
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Dec 17, 2006
#8
  • Dec 17, 2006
  • #8
Check fuse #8 in the central junction fuse panel ( under the dash)

Your problem is either that fuse or a open in circuit 391 RD/YE before splice #117

If it's the fuse ( 99 percent of the time it is) then the root cause is most likely a short or intermintent short in a 02 sensor heater

EDIT.......

After reading you original post one more time, I think your root cause could also be a chaffed or otherwise damaged circuit 391.. check all wiring near the pedals.
 
G

GTCharles

New Member
Dec 20, 2005
18
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0
Portland, OR
Dec 17, 2006
#9
  • Dec 17, 2006
  • #9
Yeah I agree with sgarlic you have to many mods to troubleshoot your problem without knowing the set up better.
 

aleborjas

New Member
Sep 11, 2005
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Dec 17, 2006
#10
  • Dec 17, 2006
  • #10
i cheked all fuses they are all fine i looking to get the EGR sensors new i hope thats the problem!
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Dec 17, 2006
#11
  • Dec 17, 2006
  • #11
aleborjas said:
i cheked all fuses they are all fine i looking to get the EGR sensors new i hope thats the problem!
Click to expand...



No just swapping in sensors WILL NOT FIX THIS...

I am 100 percent sure you have either a blown number #8 fuse in the central junction box or a open on circuit 391.. that is the ONLY thing that can cause the circuit faults you have.

Did you check the fuse in the box under the dash, you are aware that the car has two fuse boxes right?
 

aleborjas

New Member
Sep 11, 2005
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Dec 18, 2006
#12
  • Dec 18, 2006
  • #12
off course i cheked all fuses the ones on the engine bay andunder the dash all fine
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Dec 18, 2006
#13
  • Dec 18, 2006
  • #13
aleborjas said:
off course i cheked all fuses the ones on the engine bay andunder the dash all fine
Click to expand...


Sorry I just had to be sure, some people are not aware that there is two fuse boxes.Since the fuse is fine now you need to see if you have power to the sensors in question.

Check to see if you have power at the EVR wire RD/YE you should have 12 volts there.

We know the problem has to be in circuit #391 because the codes are for circuit faults for all the components that get power from 391.. the only components on that circuit that you don't have a circuit fault for would be the rear 02 sensors but with your mods the rear 02's would be shut off in the tune.

If you have power to those components try to wiggle the harness all the way from the back of the underdash fuse panel all the way to the pcm and intot he engine comartment while testing for power you may have a intermintent problem caused by a chaffed wire.
 
0

02GTstangGT02

New Member
Dec 1, 2006
17
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0
Dec 19, 2006
#14
  • Dec 19, 2006
  • #14
I can tell that these codes below are getting thrown off by whats originally causing the problem.
(i.e. a bad MAF will cause your car to run lean or rich causing your O2 sensors to throw a code)
In my case I had 12codes come up and it was either my MAF or IAC
I replaced both and disconnected my battery and my car was fine after that.

P0135 - HO2S SENSOR CIRCUIT MALFUNCTION (HO2S-11)
P0155 - HO2S SENSOR CIRCUIT MALFUNCTION (HO2S-21)
P1409 - EGR VACUUM REGULATOR SOLENOID CIRCUIT MALFUNCTION
P1451 - EVAPORATIVE EMISSION SYSTEM VENT CONTROL CIRCUIT

and please think before you type
 
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