94 century 2.2L engine misses
chevy55
08-17-2007, 12:45 AM
94 century cylinder 4 not getting spark. Complete rebuild on motor 30-40,000 miles ago, has new plugs and wires. Just recently started to miss. Put new coil packs and ignition module and still misses. I have narrowed the miss down to cylinder 4. I put a timing light on cylinder four and the light flashes once every 3-4 seconds so I am assuming it to be electrical. the only thing i havent changed is the cps but everything i have read sounds like if the cps is faulty it wont run at all, and even with the miss the car still runs strong and wont die. Not sure what to do now. Any suggestions or comments?
GTP Dad
08-17-2007, 01:16 PM
Welcome to AF!!
Unfortunately, I am not very well versed in this engine, so I have a question. Is this port or throttle body injected? If it is port injected then the injector is probably bad. If throttle body injected then I suggest you pull the plug and check it. If it looks good go ahead and do a compression check. The compresion check will tell you what is going on inside the cylinder. I suspect you may have an issue with a burnt valve or a bad lifter that is causing the miss.
Unfortunately, I am not very well versed in this engine, so I have a question. Is this port or throttle body injected? If it is port injected then the injector is probably bad. If throttle body injected then I suggest you pull the plug and check it. If it looks good go ahead and do a compression check. The compresion check will tell you what is going on inside the cylinder. I suspect you may have an issue with a burnt valve or a bad lifter that is causing the miss.
richtazz
08-17-2007, 04:47 PM
If it's a spark issue on cylinder 4, only 4 things can cause no spark on only one cylinder. Bad plug, wire, coil or ignition module. Just because you replaced a part, doesn't mean it still isn't bad.
You can rule the coil by swapping them around. If the miss moves with the coil, there's your problem.
You can do the same with the plug wires and spark plugs. The ignition module is trickier to test, but can cause a mis-fire on only one cylinder also.
You can rule the coil by swapping them around. If the miss moves with the coil, there's your problem.
You can do the same with the plug wires and spark plugs. The ignition module is trickier to test, but can cause a mis-fire on only one cylinder also.
chevy55
08-18-2007, 02:12 AM
Ill try switching the coils tomorrow and the plugs and wires and see what I come up with. If that doesnt do it, how would you test the ignition module?
richtazz
08-21-2007, 06:59 AM
If you have an Auto-Zone or Advance in your area, they can test it for free. Make sure they run the test multiple times to get the module warm, as they can work cold, but fail when warm. Another forum member had a similar problem (but it was cylinder 2), and it ended up being the new ignition module he'd just purchased was bad.
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