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I have been changing the EFI sensors on my '85 302 and have found that the truck did not have a knock sensor. The harness connection had a plastic vacuum cap over the connection.
When I pulled the codes off the ECM it flashed 11-11; which I think is system pass. With no Knock sensor how does the system pass?
I am still struggling with low power at high end - it has gotten a little better with a new TBPS; but, still not the power it should have.
Some applications did not use a knock sensor. If you are getting a 11, the computer and it's sensors are good. You are using a lot of fuel at full throttle, so I would check the fuel pressure with a gauge. You can tape the gauge to the windshield and take a test drive to see if it holds. I assume you have changed the fuel filter? Also check for a filter in the valve assembly if you have dual tanks. I have heard rumors on here that there is another filter in the tank switching valve.
Thanks Dave; however, it looks like there was once a Knock sensor installed.
I have changed the fuel filter - I looked at the change over valve and it does not look like it woul dhave a filter - I'll look again.
On the fuel pressure gauge - I can not find a shrader on the fuel manifold. I have looked all over the driver's side manifold and can not see much of the passenger side. To my knowledge, there is not a connection. The Truck is an '85 with the optional EFI 302 - not sure if fuel manifold had a shrader on this model?
You are probably right, I have heard some of the early models did not have the test port. I don't know how else to check the fuel pressure without butchering one of the lines.
They show two types of filters for your truck? I am not sure, I never have worked on that model.
It's the paper cartridge - it's a B*$@H to change - the housing screws off & on like an oil filter - except you get about a gallon of fuel all over the place and the o-ring gasket is hard to get sealed - other than that - it's not too bad.