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HELP

  • Thread starter Thread starter christianbr
  • Start date Start date May 15, 2009
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christianbr

New Member
May 15, 2009
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huntsville al
May 15, 2009
#1
  • May 15, 2009
  • #1
i have an 89 5.0 lx 5 speed . the motor is bored 40 0ver and has a mild cam 512 intake and exhaust lift, heads have 196 160 valves ported exhaust port double springs, 7/16 studs scorpion 1.6 rolor rockers. exhaust : bbk long tube headers off road h-pipes and 2 chamber flowmaster mufflers. 110lbh fuel pump bbk adj fuel press. regulator. summit 19lb injectors. gt40 intake 1 in spacer 70mm throttle body , c&l mass air and tube. my problem is i have to have the fuel pressure at 60 psi or it wont idle and pops through the intake and has seemed to lost some power . i ran the codes and it came up 67nds circuit open/with ac on during self test 67 rpm not with in self test range 85canister purge circuit failure 95air fuel mixture not within self test range 95 thermactor air system inop. PLEASE HELP ! this is my only vehicle
 

Strippt88

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Nov 24, 2006
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Cedar Lake, Indiana
May 15, 2009
#2
  • May 15, 2009
  • #2
5.0 Tech, ask jricher
 

FrankenStang

Now, give me a damn CT!
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May 15, 2009
#3
  • May 15, 2009
  • #3
Strippt88 said:
5.0 Tech, ask jricher
Click to expand...

 

jrichker

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May 15, 2009
#4
  • May 15, 2009
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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:



Code 95 Key On, Engine not Running - the following test path is for 86-90 model Mustangs.

The 95 code is because at one time or another, the fuel pump relay hiccupped and didn't provide power the pump when the computer told it to run. Sometimes this is a one time thing, other times it is a no run or runs poorly condition.

Suspect items are bad fuel pump relay, corrosion in the fuel pump relay socket, inertia switch, wiring damage , corroded connector contacts.



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 driver’s 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. 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. If there is good voltage there & at the Pink/black wire, swap the relay.

Some Mass Air conversions neglect to run the extra fuel pump wire, and they always have a 95 code. See MAF - Mustang Mass Air Conversion - StangNet - The Mustang Network for more information on the Mass Air wiring conversion.




The above items may not do much for your idle problems.

The fix for idle problems is below...

See the "Surging Idle Checklist for help with all your idle/stall problems. Everything you need to find and fix idle problems is in there.

The first two posts contain all the updates to the fixes. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.
 
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