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Updated my software for my scanner today and did the induces vacuum test. It didn’t change the fuel trims. But I did find out that the catalyst is toast and is more than likely partially clogged and causing too much back pressure on the engine. I suspect at this point that it’s causing incomplete combustion and not slowing enough fresh air into the cylinders and causing the rich running condition. So for now the project is on hold until I have the time and money to replace the catalyst.
Updated my software for my scanner today and did the induces vacuum test. It didn’t change the fuel trims. But I did find out that the catalyst is toast and is more than likely partially clogged and causing too much back pressure on the engine. I suspect at this point that it’s causing incomplete combustion and not slowing enough fresh air into the cylinders and causing the rich running condition. So for now the project is on hold until I have the time and money to replace the catalyst.
0 2018/09/12 16:59:52
0 2018/09/12 13:25:03
Looking at the fuel trims and sensor voltages today I'm leaning towards a clogged Catalytic converter. Too much back pressure can make an engine starve for air and have bad combustion. Its really the only thing at this point that makes sense. I've checked everything upstream and the 02 sensors are reading correctly. You can see from the graph that the down stream sensor is matching the upstream sensor. So project is on hold until I get time and money to install a new one. I'll keep you posted.
Looking at the fuel trims and sensor voltages today I'm leaning towards a clogged Catalytic converter. Too much back pressure can make an engine starve for air and have bad combustion. Its really the only thing at this point that makes sense. I've checked everything upstream and the 02 sensors are reading correctly. You can see from the graph that the down stream sensor is matching the upstream sensor. So project is on hold until I get time and money to install a new one. I'll keep you posted.
0 2018/09/12 13:18:42
This is what the inside of the plenum looks like. The CFI spider is located inside the intake plenum along with the spider fuel lines and pressure regulator. It’s an all in one unit. Mine is new and been in for around 15 months.
This is what the inside of the plenum looks like. The CFI spider is located inside the intake plenum along with the spider fuel lines and pressure regulator. It’s an all in one unit. Mine is new and been in for around 15 months.
0 2018/09/11 20:51:33
0 2018/09/11 20:50:48
-21.5 cylinder #1 but the engine in my truck doesn’t have an adjustable distributor. Tried that route already. It goes in. Locks in place and doesn’t have any timing marks in the front of the enigine. It uses pulse width timing.
-21.5 cylinder #1 but the engine in my truck doesn’t have an adjustable distributor. Tried that route already. It goes in. Locks in place and doesn’t have any timing marks in the front of the enigine. It uses pulse width timing.
0 2018/09/11 20:11:14
0 2018/09/11 18:52:24
These are the last freeze frames from when the code has shown up. P0172.
These are the last freeze frames from when the code has shown up. P0172.
0 2018/09/11 18:52:24
0 2018/09/11 18:52:24