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Engine Having a misfire issue on one cylinder

  • Thread starter Thread starter 93Modfox
  • Start date Start date Jun 27, 2020
9

93Modfox

Member
Jun 27, 2020
6
1
13
Indiana
Jun 27, 2020
#1
  • Jun 27, 2020
  • #1
Hi guys, I seriously need some help here.
Here’s a little backstory.. bought a roller, put an engine in it and it was running decent until I realized my regulator was bad. Swapped it and now I keep running rich in 7 cylinders but number 2 looks clean. I’ve swappped injectors, plugs, wires, cap and rotor, control module and have had no change.
what would cause only number two cylinder to be clean (smells like fuel)?
Ran like this with the A9L ecu and still with the megasquirt.
 
9

93Modfox

Member
Jun 27, 2020
6
1
13
Indiana
Jun 27, 2020
#2
  • Jun 27, 2020
  • #2
93Modfox said:
Hi guys, I seriously need some help here.
Here’s a little backstory.. bought a roller, put an engine in it and it was running decent until I realized my regulator was bad. Swapped it and now I keep running rich in 7 cylinders but number 2 looks clean. I’ve swappped injectors, plugs, wires, cap and rotor, control module and have had no change.
what would cause only number two cylinder to be clean (smells like fuel)?
Ran like this with the A9L ecu and still with the megasquirt.
Click to expand...
 

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R

rockyracoon

10 Year Member
Nov 23, 2005
874
27
49
margate NJ
Jun 27, 2020
#3
  • Jun 27, 2020
  • #3
Is it possible that number 2 injector was not pulsing, hence not fouled like the others ?
 
9

93Modfox

Member
Jun 27, 2020
6
1
13
Indiana
Jun 27, 2020
#4
  • Jun 27, 2020
  • #4
Well, I’ve been through everything. Ignition and fuel, everything checked out fine. I decided to do a compression test and found #2 cylinder was a big goose egg, 0 compression. Now I need to figure out if it’s in the head or at the piston.
 
R

rockyracoon

10 Year Member
Nov 23, 2005
874
27
49
margate NJ
Jun 28, 2020
#5
  • Jun 28, 2020
  • #5
Consider running a leakdown test if you have a tester. Or even just take the check valve out of your compression tester hose and listen for where air is escaping.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,915
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203
polk county florida
Jun 28, 2020
#6
  • Jun 28, 2020
  • #6
93Modfox said:
Well, I’ve been through everything. Ignition and fuel, everything checked out fine. I decided to do a compression test and found #2 cylinder was a big goose egg, 0 compression. Now I need to figure out if it’s in the head or at the piston.
Click to expand...
or a valve
 
Reactions: kiddiccarus
9

93Modfox

Member
Jun 27, 2020
6
1
13
Indiana
Jun 28, 2020
#7
  • Jun 28, 2020
  • #7
I did put air to it last night. Exhaust valve is stuck open. It seems to be from the lifter/pushrod side. I’m going to tear into it here shortly.
 
Reactions: General karthief
9

93Modfox

Member
Jun 27, 2020
6
1
13
Indiana
Jun 28, 2020
#8
  • Jun 28, 2020
  • #8
I backed the rocker off and the valve closed. Put air to it again and determined that the valve was completely shut and the rings were fine (leak down). I must have a lifter issue of some kind. This happened out of nowhere.. anyone ever had an issue like this?
 
9

93Modfox

Member
Jun 27, 2020
6
1
13
Indiana
Jun 30, 2020
#9
  • Jun 30, 2020
  • #9
Problem resolved, stuck lifter.
 
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