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engine stalls when trying to run KEOR test

  • Thread starter Thread starter 50 Proof
  • Start date Start date May 31, 2009
5

50 Proof

Member
Jul 14, 2003
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1
9
Orange County
May 31, 2009
#1
  • May 31, 2009
  • #1
My buddy has a 1988 Mustang, california car with Mass Air. He gets a check engine light when driving the car. When we try to run a key on engine running test, the engine stalls as soon as the computer tries to go into self test mode. We ran a key on engine off test and got codes 67 and 85. We're going to replace the vacume lines going to the charcoal canisters but I doubt this will fix the issue with his engine stalling when trying to run the KOER test. Any suggestions? Thanks
 

Brian992V

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Feb 11, 2000
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Lexington,KY
May 31, 2009
#2
  • May 31, 2009
  • #2
The computer won't let you because of code 67. You'll have to ground PIN 30 on the computer. Jrichker has a great write up on how to do this. I used this method and it worked great.
 

jrichker

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Jun 1, 2009
#3
  • Jun 1, 2009
  • #3
Code 67 - clutch not depressed (5 speed) or car not in neutral or park (auto) or A/C in On position when codes
where dumped. Possible neutral safety switch or wiring problem. This code may prevent you from running the Key On
Engine On tests. You can generally ignore this code, since it has no effect on engine performance.

The computer wants to make sure the A/C is off due to the added load on the engine for the engine running tests. It also
checks to see that the transmission is in Neutral or the clutch depressed (T5, T56, Tremec 3550 & TKO)). This prevents
the diagnostics from being run when the car is driven. Key On Engine Running test mode takes the throttle control away
from the driver for several tests. This could prove hazardous if the computer was jumpered into test mode and then driven.

The NSS code 67 can be bypassed for testing. You will need to temporarily ground computer pin 30 to the chassis.
Computer pin 30 uses a Lt blue/yellow wire. Remove the passenger side kick panel and then remove the plastic cover from
the computer wiring connector. Use a safety pin to probe the connector from the rear. Jumper the safety pin to the
ground near the computer.

IF YOU JUMPER THE WIRING TO BYPASS THE NSS, BE SURE TO REMOVE IT PRIOR TO DRIVING THE CAR!!! YOU COULD END UP CRASHING AND BURNING!!!

Code 85 - CANP solenoid - The Carbon Canister solenoid is inoperative or missing. Check vacuum lines for leaks and cracks. Check electrical wiring for loose connections, damaged wiring and insulation. Check solenoid valve operation by grounding the gray/yellow wire to the solenoid and blowing through it.
The computer provides the ground for the solenoid. The red wire to the solenoid is always energized any time the ignition switch is in the run position.

Charcoal canister plumbing - one 3/8" tube from the bottom of the upper manifold to the rubber hose. Rubber hose connects to one side of the canister solenoid valve. Other side of the solenoid valve connects to one side of the canister. The other side of the canister connects to a rubber hose that connects to a line that goes all the way back to the gas tank. There is an electrical connector coming from the passenger side injector harness near #1 injector that plugs into the canister solenoid valve. It's purpose is to vent the gas tank. The solenoid valve opens at cruse to provide some extra fuel.



It does not weigh but a pound or so and helps richen up the cruse mixture. It draws no HP & keeps the car from smelling like gasoline in a closed garage. So with all these good things and no bad ones, why not hook it up & use it?

Purge valve solenoid:


Carbon Canister:
 
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