Engine Cylinder balance test acting up

sav22rem22

Active Member
Feb 6, 2020
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So I did a code dump today on my 89 Gt just to see how everything’s doing after the explorer intake install and everything is good except I got a code 96 although I believe this is when I removed my fuel pump relay to relieve fuel pressure. However when I did the cylinder balance test it sounded like it only tested one cylinder and then it immediately idled down and gave me a code 7 several times. Isn’t it supposed to at least do the other cylinders first?? I don’t notice any missing and the injectors are all working.
 
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Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
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The CBT goes by pretty quick. Idles up a tad and shuts off the injectors one at a time. 7 would indicate cyl 7 is not firing so I would investigate that one. Pull the spark plug, test the injectors, check spark on the wire
 

sav22rem22

Active Member
Feb 6, 2020
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North Carolina
The CBT goes by pretty quick. Idles up a tad and shuts off the injectors one at a time. 7 would indicate cyl 7 is not firing so I would investigate that one. Pull the spark plug, test the injectors, check spark on the wire
Well I’ve done a lot of cbts before and they usually take about at least a few minutes but this one took about 45 seconds which has never happened before. I’ll probably run another one soon to see if that was just a fluke but if not I’ll pull the plugs and start investigating
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,515
12,465
224
Massachusetts
I am not 100% sure on this because it’s been a while since I looked into it, but if the system detects a bad misfire I believe it ends the test.

don’t quote me on that one.
 

sav22rem22

Active Member
Feb 6, 2020
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North Carolina
I am not 100% sure on this because it’s been a while since I looked into it, but if the system detects a bad misfire I believe it ends the test.

don’t quote me on that one.
Hmm could be the case. I’ll check tomorrow and come back with an update. After doing the cbt I went and did a few backroad pulls and it felt great except for when I let off the throttle after about 5 seconds there was a pop from the exhaust.
 

sav22rem22

Active Member
Feb 6, 2020
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North Carolina
17697812-5503-465F-BED8-C553B3ACB7F9.jpeg

Pulled the #7 plug and this is what it looks like. It looks more white than it is but it’s more of a grey. Here’s the top of it
2FAF450F-30A8-4944-A33D-1C9F0AE80509.jpeg

What do you guys think? They all pretty much look like this they’re all a lightish grey color