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#1
06-09-2007, 12:22 AM
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'74 Cad Eldorado Engine Pinging BAD
What would cause a engine to ping so bad your afraid to touch the gas pedal? I'm working on a 74 Eldorado, I know its not a Pontiac, but I'm using the money from it for my Pontiac
 . I haven't checked the timing yet, I need to get the specs, but I did notice the EGR valve was disconnected, would this cause pinging? What is the vacuum source for the EGR valve? What about the distributor weights, could they be stuck? Any other ideas? Thanks
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#2
06-09-2007, 01:28 AM
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anything could be the problem, seems like you are on the right track. Check everything and make sure they are using premium fuel and see what is up after that.
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70 GTO 462 E-Heads TKO-600 9-Inch/3.60's |
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#3
06-09-2007, 01:51 PM
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yes i think the EGR will cause pinging if it is disconnected
i think it connects to off idle vacuum
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1980 TA 455 th400 2.56 posi 12.27@111.48 http://www.dragtimes.com/Pontiac-Tra...lip-29967.html http://www.youtube.com/watch?v=6X5XJ9PR1Qw https://www.youtube.com/user/hal101/videos |
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#4
06-09-2007, 07:02 PM
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Make sure the timing's near factory specs, and use premium gas. If it's still real bad you'll have to start digging deeper, maybe much deeper. If it's carbon deposits inside the combustion chamber, folklore has it that one can drizzle water into the carb (or for fuel injection whatever they call the air inlet) at high idle to clean the deposits. I'm sure there are chemical aids (a fuel additive of some sort) that will claim to help also.
I bought a 400 motor once; the guy had cut the heads down and put domed pistons in it to get over 12.5 to 1 compression. It was absolutely horrible for pinging. I ended up putting flat-top pistons in it and a thicker head gasket finally. |
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#5
06-09-2007, 10:48 PM
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Back in those years they started emission controls and the EGR valve was a key component. You need to connect it and make sure it's working, it will help the pinging, perhaps even eliminate it.
George
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"...out to my ol'55, I pulled away slowly, feeling so holy, god knows i was feeling alive"....written by Tom Wait from the Eagles' Live From The Forum |
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#6
06-10-2007, 05:59 PM
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Hooked the EGR valve back up, and reset the timing. The pinging has decreased about 50%. Does retarding the timing a little help? The motor also sees to have a little blow by, is this contributing to the problem? Thanks
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