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Would a bad injector throw a code?

  • Thread starter Thread starter aar0s
  • Start date Start date Aug 4, 2011

aar0s

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Dec 20, 1998
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Aug 4, 2011
#1
  • Aug 4, 2011
  • #1
Im trying to diagnose a problem that ive had for a while thats not throwing a code and i'm wondering if it could be some kind of fuel problem. Im wondering if a bad injector would give a code if it was missfireing?
 

ID89GT

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May 26, 2008
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Aug 5, 2011
#2
  • Aug 5, 2011
  • #2
I would imagine it would throw a lean code due to the air in that cylinder not burning, but I'm not sure. I'm sure someone else would know for sure
 

Mustang5L5

That is…until I whipped out my Bissell
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#3
  • Aug 5, 2011
  • #3
If you run a cylinder balance test, it will come up as a weak cylinder
 

aar0s

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Dec 20, 1998
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#4
  • Aug 5, 2011
  • #4
cant run any KOER tests because the car use to be a five speed and it was converted to a auto (before i got it) and they kept the five speed computer so im getting the neutral safety switch code and it wont let the computer do the test.
 

Mustang5L5

That is…until I whipped out my Bissell
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Feb 18, 2001
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Aug 5, 2011
#5
  • Aug 5, 2011
  • #5
aar0s said:
cant run any KOER tests because the car use to be a five speed and it was converted to a auto (before i got it) and they kept the five speed computer so im getting the neutral safety switch code and it wont let the computer do the test.
Click to expand...

You can bypass that by putting a jumper wire at the EEC. You could probably even put in a toggle switch so any time you want to run the codes, you can just flip the toggle and run them.

Small speed bump, but being able to do engine codes/CBT is helpful.

What year is your car so i can check diagrams and tell you what pin to jump out?
 

aar0s

Founding Member
Dec 20, 1998
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Aug 5, 2011
#6
  • Aug 5, 2011
  • #6
its an 88, I tried the jumper at the clutch harness next to the brake peddle trick and it didnt work.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,179
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Aug 5, 2011
#7
  • Aug 5, 2011
  • #7
That won't do it.

I'll check in the AM...I have the diagrams.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Aug 6, 2011
#8
  • Aug 6, 2011
  • #8
It's pin 30 that gets grounded as I recall. Wait for confirmation on that..............
 

jrichker

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#9
  • Aug 6, 2011
  • #9
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.
Be sure to remove the jumper BEFORE attempting to drive the car!!!

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 and 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.
 

aar0s

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#10
  • Aug 6, 2011
  • #10
Are the pins numbered on the computer? just because its sposta be lt blue and yellow dont mean that it is, as im finding out on my heap.
 

jrichker

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#11
  • Aug 7, 2011
  • #11
See Mustang Mass Air Conversion « for a picture of the wire side of the computer wiring connectors. There are lots of front side views, but you have remember that when you flip the connector over what was right is now left, and what was left is now right.
 

aar0s

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Dec 20, 1998
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Aug 7, 2011
#12
  • Aug 7, 2011
  • #12
thanks guys, Ill subscribe to this for easy finding but it will probably have to wait till it cools off in the garage a little before I can get in there and do it. Thanks for the info!
 
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