99 frc started running rough, code 1416?
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Melting Slicks
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From: Milton, West Virginia
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99 frc started running rough, code 1416?
Hey Guys, My 99 has started running rough, missing even backfires at times, code PO 1416 keeps popping up also code PO 300 one time, I have researched this code and can replace the check valves myself. I was just wondering if these check valves could cause the engine to miss? Under acceleration engine seems to run fine, miss shows up while at idle and normal driving. My car just has 34,000 miles, thanks!
Last edited by 3Vettes@Home; Sep 16, 2016 at 11:25 AM.
Thread Starter
Melting Slicks
Joined: Sep 2000
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From: Milton, West Virginia
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Clear ALL the codes you have. Next time the car is running rough pull the codes BEFORE you shut off the engine. Some codes can disappear once the engine is cycled OFF.
To pull codes with the engine running you need to use the reset key to clear all messages displayed in the DIC. Then pull codes as normal.
To pull codes with the engine running you need to use the reset key to clear all messages displayed in the DIC. Then pull codes as normal.
Melting Slicks
Joined: Sep 2011
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From: Appleton WI
You may want to check the connections between your air cleaner and intake. If you are getting unmetered air into the system, the engine can run rough. On my car, the connection at the front of the accordion has a tendency to slip off. When it does my idle changes.
Last edited by 3sACROWD; Sep 17, 2016 at 04:58 PM.
Thread Starter
Melting Slicks
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From: Milton, West Virginia
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Thanks I'll check that connection too..
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Melting Slicks
Joined: Sep 2000
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From: Milton, West Virginia
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Update!
I checked all connections, they were good, I pulled the plugs and found one was fouled. Bought NGK TR55 plugs which is what is in the car, changed the one plug and the miss has been corrected! I'm now going to change all of the plugs (Advance Auto had them in stock for $2.49 each) Does anyone remember the gap for these plugs? I am running AFR 205 heads, 30lb injectors, Z06 intake manifold, modified throttle body, cold air intake and long tube headers. The current gap on the exixting plugs are .055 Thanks for your help! 
Last edited by 3Vettes@Home; Sep 19, 2016 at 04:24 PM.
