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Code P1233 HELP please!

  • Thread starter Thread starter the98stang
  • Start date Start date Sep 30, 2006

the98stang

Active Member
Aug 12, 2005
2,408
0
47
Clovis, CA
Sep 30, 2006
#1
  • Sep 30, 2006
  • #1
I'm getting really frusterated with my mustang. For MONTHS it had terrible idle. I replaced the IAC, PCV and grommet, fuel filter, plugs, cleaned the filter, and it STILL idles like sh1t. But it would only happen while braking. Car idles fine at start up. But if I'm driving and put it in N, it drops all the way down to 0 rpm's and dies. Same thing happens while braking. I have to keep revving the car for it not to die. It used to happen occasionaly, but now the problem is definetely there.

Today was the first time the "service engine soon" light came on. But here is the story behind it. I wanted to program my PCM back to stock, so I pulled the fuel pump fuse as well as the fan fuse (Maybe that's why its showing code P1233 FPDM offline). Then I flashed the car back to stock. I put the fuses back. During all this, I was messing with my shifter console area because it was sqeeking, and that caused my speedcal wiring to get messed up. So I was driving and noticed the speedo wasn't working. I knew it was because I was messing with it earlier. No biggie. THEN my odometer disappears and shows (--------) . And shortly after, the CEL. And every time I braked or put it in (N) while moving she died or came very close to dieing. I pulled the codes and these came up:

1. P0720 Output Shaft Speed Sensor circuit.
2. P1000 OBD-II Monitor Testing Incomplete.
3. P1233 Fuel Pump Driver Module off-line.

I assume the 1st code is related to the speedcal. I don't think the 2nd one is relevant. But what about P1233? I have searched and a lot people relate this to faulty fuel pumps. But many people say to check the fuses and FPDM connections. Based on my observations, what do you think is causing this code to occur? Considering my idle has been weird like this for a while, I don't think it's related to my Xcal2 tuning. So what can I do? PLEASE HELP! Thanks..

Tanner
 

Rickey_Bobby

New Member
Nov 8, 2006
332
0
0
Sarasota, FL
Nov 21, 2006
#2
  • Nov 21, 2006
  • #2
hmm, I have the same problem with idle. I ALSO just got a code P0720. But my speedo and tach still work. And I'm using a flashed diablo chip. so I doubt its something u messed up. Mine started out of nowhere. Did you get anywhere with your idle problem?
 
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