Engine Miss driving me nuts.
Thread Starter
Intermediate
Joined: Aug 2015
Posts: 42
Likes: 2
From: Bonney Lake Washington
Engine Miss driving me nuts.
ok so I have this miss. I have already changed all 4 o2 sensors, plugs wires and fuel filter/regulator. I have checked to make sure that I do not have any broken valve springs and I don't. I can take the plug wire off the coil and I do have spark. I have ohm checked the new wires and they are good the plugs are gapped correctly and are the recommended ones from the forum. I have also replaced the pcv and the other vacuum hose in that area. I have had the p0300 cel as well as random others p0174 I think, it has also said that the miss was on #7
So I have been told that some of the ls motors have been notorious for intakes leaks and it was recommended to me to change out the intake gaskets (that could fix it), and at the same time change the oil press. sending unit and that pesky air valve behind the head and intake. What are your thoughts as I haven't done it yet?
I don't have a problem with all the parts I have installed because they are (to me) considered preventive maintence. I'm just stumped with this and any help would be greatly appreciated.
So I have been told that some of the ls motors have been notorious for intakes leaks and it was recommended to me to change out the intake gaskets (that could fix it), and at the same time change the oil press. sending unit and that pesky air valve behind the head and intake. What are your thoughts as I haven't done it yet?
I don't have a problem with all the parts I have installed because they are (to me) considered preventive maintence. I'm just stumped with this and any help would be greatly appreciated.
Thread Starter
Intermediate
Joined: Aug 2015
Posts: 42
Likes: 2
From: Bonney Lake Washington
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Racer
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From: Gulf Shores AL
I've lived this dream. You've gone through the basics, good methodical diagnostics will eliminate possibilities. In my case I went through everything in this thread and eventually took it to a shop, who were able to fix to with a crank position relearn process.
https://www.corvetteforum.com/forums...from-hell.html
https://www.corvetteforum.com/forums...from-hell.html
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I was thinking the same, there is a bracket on the drivers side rear of the intake that is held down with intake bolts and the injector/coil harness runs right behind it... after years of use it begins to wear through the harness and cause all kinds of issues, if I ever take the intake off I never put that bracket back on... it might be worth a shot to peel the loom back and look for any damaged wires... if you want to check for intake leaks you can make a contraption that will allow you to pressurize the intake, I have seen some people use a block of wood with an air fitting inserted into it that will fit into a silicone coupler and you attach this to the throttle body... you can use this to add some pressure (a few pounds is fine, you don't want to add a bunch and blow your seals out) into the intake and you will be able to hear any leaks
Last edited by StingrayRebel; Nov 20, 2016 at 10:38 AM.