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Need help with codes 87 and 96

  • Thread starter Thread starter broncobuddha
  • Start date Start date Apr 20, 2004

broncobuddha

Founding Member
Jan 10, 2001
123
0
0
Knoxville, TN
Apr 20, 2004
#1
  • Apr 20, 2004
  • #1
Been having pinging problems with my coupe for a few weeks now. Seems to ping no matter what timing I run it at. It's currently at 15* initial. Figured this was the EGR and unplugging the vacuum line to it stopped the pinging. Made my low rpm bucking worse but hey...

So... I ran the KOEO codes last night and here's what I came up with:

Here it goes:

67: Neutral Drive Switch circuit failure or AC input high or Clutch switch circuit failure- probably due to my leaving the car in first during KOEO.

85: which is the canister readings due to my not having a smog pump.

I got these twice.

2nd set of KOEO:

33: EGR not opening properly. Confirms my EGR problems.

87: Fuel Pump Primary circuit fault.

96: Fuel Pump secondary circuit fault/ high speed fuel pump relay open.

I don't understand the 87 or 96. I replaced the fuel pump when I did the v8 swap, so, what's wrong? I'm getting fuel otherwise it wouldn't run.

Any ideas?

Thanks.
 

broncobuddha

Founding Member
Jan 10, 2001
123
0
0
Knoxville, TN
Apr 21, 2004
#2
  • Apr 21, 2004
  • #2
ttt anyone know? This was a 4cyl to 5.0 conversion if that helps.

Thanks.
 

jrichker

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Apr 21, 2004
#3
  • Apr 21, 2004
  • #3
Code 87 – fuel pump primary circuit failure. check inertia switch, wiring to/from inertia switch, red wire going to inertia switch for +12volts. Check other side of inertia switch for +12 volts.

To help troubleshoot the 87 code, follow this link for a wiring diagram http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Code 96 – KOEO- Fuel pump monitor circuit shows no power - Fuel pump relay or battery power feed was open - Power / Fuel Pump Circuits.

Look for a failing fuel pump relay, bad connections or broken wiring. The fuel pump relay is located under the Mass Air Meter on Fox bodied stangs built after 91. On earlier model cars is under the passenger seat. On MASS Air Conversions, the signal lead that tells the computer that the fuel pump has power may not have been wired correctly. See http://www.stangnet.com/tech/maf/massairconversion.html

To help troubleshoot the 96 code , follow this link for a wiring diagram http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Look for power at the fuel pump - the fuel pump has a connector at the rear of the car with a pink/black wire and a black wire that goes to the fuel pump. The pink/black wire should be hot when jumpered to the test position. . To trick the fuel pump into running, find the ECC test connector and jump the connector in the lower RH corner to ground. http://www.mustangworks.com/articles/electronics/eec-iv_codes.html for a description of the test connector. it. No voltage when jumpered, check the fuel pump relay and fuse links.

Using the diagram, check the red/black wire from the fuel pump relay: you should see 12 volts or so. If not, check the inertia switch: on a hatch it is on the drivers side by the taillight. Look for a black rubber plug that pops out: if you don't find it, then loosen up the plastic trim. Check for voltage on both sides of the switch. If there is voltage on both sides, then check the Pink/black wire on the fuel pump relay: it is the power feed to the fuel pump. Good voltage there, then the fuel pump is the likely culprit since it is getting power. No voltage there, check the Orange/Lt blue wire, it is the power feed to the fuel pump relay & has a fuse link in it. Good voltage there & at the Pink/black wire, swap the relay.

Code 85 - CANP solenoid (ALL 1989) - Solenoids the Carbon Canister solenoid is inoperative. Check vacuum lines for leaks and cracks. Check electrical wiring for loose connections, damaged wiring and insulation. Check solenoid valve operation by applying 12 volts to the solenoid and blowing through it. The carbon canister vents the fuel tank and has nothing to do with the smog pump.
 
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