Cyl 1 and 2 not working when engine warm
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Cyl 1 and 2 not working when engine warm
I am helping a friend with an junk yard engine swap because the old engine over heated, this is my 5th engine swap but my first Honda.
The Car is a 94 Accord EX 4 Cyl. I believe the new junk yard engine is from a 95 Accord ex. The engine runs great when it is cool but after warming up, it starts running very rough. We have determined that when warm it is only running on Cyl. 3 and 4. We can unplug the spark plug wire from cyl 1 and 2 with out effecting the engine. We know the Cam shaft and crank shaft are timed correctly, Not sure about the computer controlled timing. We know we are getting spark and fuel in Cyl 1 and 2. The compression in all 4 Cyl. was 160-170. We have cleaned the FITV. I am out of ideas because it runs great when cool. Rather than taking it to Dealer ship I figured I would ask the real experts here first.
Thanks in advance.
The Car is a 94 Accord EX 4 Cyl. I believe the new junk yard engine is from a 95 Accord ex. The engine runs great when it is cool but after warming up, it starts running very rough. We have determined that when warm it is only running on Cyl. 3 and 4. We can unplug the spark plug wire from cyl 1 and 2 with out effecting the engine. We know the Cam shaft and crank shaft are timed correctly, Not sure about the computer controlled timing. We know we are getting spark and fuel in Cyl 1 and 2. The compression in all 4 Cyl. was 160-170. We have cleaned the FITV. I am out of ideas because it runs great when cool. Rather than taking it to Dealer ship I figured I would ask the real experts here first.
Thanks in advance.
Honda-Tech Member
Joined: Jan 2004
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From: New England, USA
Re: Cyl 1 and 2 not working when engine warm
I am helping a friend with an junk yard engine swap because the old engine over heated, this is my 5th engine swap but my first Honda.
The Car is a 94 Accord EX 4 Cyl. I believe the new junk yard engine is from a 95 Accord ex. The engine runs great when it is cool but after warming up, it starts running very rough. We have determined that when warm it is only running on Cyl. 3 and 4. We can unplug the spark plug wire from cyl 1 and 2 with out effecting the engine. We know the Cam shaft and crank shaft are timed correctly, Not sure about the computer controlled timing. We know we are getting spark and fuel in Cyl 1 and 2. The compression in all 4 Cyl. was 160-170. We have cleaned the FITV. I am out of ideas because it runs great when cool. Rather than taking it to Dealer ship I figured I would ask the real experts here first.
Thanks in advance.
The Car is a 94 Accord EX 4 Cyl. I believe the new junk yard engine is from a 95 Accord ex. The engine runs great when it is cool but after warming up, it starts running very rough. We have determined that when warm it is only running on Cyl. 3 and 4. We can unplug the spark plug wire from cyl 1 and 2 with out effecting the engine. We know the Cam shaft and crank shaft are timed correctly, Not sure about the computer controlled timing. We know we are getting spark and fuel in Cyl 1 and 2. The compression in all 4 Cyl. was 160-170. We have cleaned the FITV. I am out of ideas because it runs great when cool. Rather than taking it to Dealer ship I figured I would ask the real experts here first.
Thanks in advance.
Long shot #1
Readjust the valve lash. It may be too tight and/or non existent. If so, the cylinder would loose compression as everything tightened for heating up.
If you haven't done so, I'd try to get a compression reading when it's the hottest, just to confirm. And I would recheck the spark Hot as well.
P
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Re: Cyl 1 and 2 not working when engine warm
No luck. We confirmed that the valve lash was good. We let the engine warm up the normal Op Temp and the compression was good at 170. I am thinking that the issue is computer related. We tested the CKP, CYP and TDC sensors and they were good as far as the Ohm's. We let the engine run for 45 minutes with out reving it up and it ran great. Then on the test drive it started acting up again. Running ONLY on cyl 3 and 4. 1 and 2 were sparking and the injectors were working fine. But when I unplug Spark plug 1's wire it did not make any differance.
