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420A Can code p1390 have causes other than timing?

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TypeONegative

5+ Year Contributor
130
15
Oct 15, 2017
Utica, New_York
My 420a has a rough idle and code p1390 and a pending code I forget code for too rich, can this be from egr or coil pack? I notice it's worse when coming to a stop fast, I just bought another engine today to build over the winter to put in the car in the spring, just wanna see if I can get it running better while still using it until November
 
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Your timing is off, it has nothing to do with the head. Set your cam gears to top dead center, remove the valve cover to verify cam position, remove plugs to verify piston position. Remove timing belt and verify crank alignment is correct

Doing the cylinder head on my gst messed up my timing marks, on a flat surface I lined up the cam gears and timing marks and inserted my alignment tool in the cam gears. I marked the positions of my belt on the cam gears and it made me double check my work because they were off.

Be sure you set the cam gears to top dead center, secure the belt with zip ties or clamps to the gears, and move the belt down to the crank.

You're off a tooth
 
Your timing is off, it has nothing to do with the head. Set your cam gears to top dead center, remove the valve cover to verify cam position, remove plugs to verify piston position. Remove timing belt and verify crank alignment is correct

Doing the cylinder head on my gst messed up my timing marks, on a flat surface I lined up the cam gears and timing marks and inserted my alignment tool in the cam gears. I marked the positions of my belt on the cam gears and it made me double check my work because they were off.

Be sure you set the cam gears to top dead center, secure the belt with zip ties or clamps to the gears, and move the belt down to the crank.

You're off a tooth
Can't thank you enough! I ended up pulling the cams a few different ways now the code is off but most of all no more idle problems it runs so good idea hate to pull it this spring, but I'm building and engine I'll get some pics of the operation tomorrow but car is running great!

Can't thank you enough! I ended up pulling the cams a few different ways now the code is off but most of all no more idle problems it runs so good idea hate to pull it this spring, but I'm building and engine I'll get some pics of the operation tomorrow but car is running great!
I owe you buddy! I can't believe how your directions worked! I used a Dremmel to put new alignment marks on the cam gears this is awesome! I'm getting in the car now to take a cruise in it. Will get pics in the morning for my engine turbo build thread, can I make this it?
 
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Lol I don't go as far as using a dremel for the marks, usually I find Tdc before removing the belt and Mark it with silver touch up paint, or my wife's nail polish. I mark the belt onto the cam gear so I know where they lay on both the intake and exhaust cam and on the crank pulley. So not only is the motor at top dead center I know tooth for tooth my belt lines back up.

When I pulled my head off I also pulled the cams out and the cam gears off. I lined the cam and gears back up at what looked to be top dead center on my work bench, but once on the car my belt marks didn't line back up and the intake and exhaust cam were both rotated inward half a tooth and I had to reset top dead center using my previous paint alignment marks on the belt and on the cam.

It is best to start another thread in the build section. Surprisingly even though the newbie section has the most clicks initially, a long thread will get passed over. The build section works the opposite way, people look for a build with multiple pages and lots of updates

Glad it all worked out for you
 
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