Engine codes

[Chris2006]

I have a 2000 Winnebago Adventurer on a Ford F53 chassis with 6.8 liter V10. I sat for 2 years. No problems starting it up and moving it or letting it run. Recently I had to replace the leveling system motor but didn't have to do any wiring. I'm getting ready to move across the country so I was checking the live data stream with OBD2 scanner and checking the AC compressor relay. No problems. I turned the motor off. When I started it again the Service Engine light was on. It has these codes now P0352 P0353 P0354 P0355 and P0443. Never had issues before. Now it has no power. I changed the plugs and coils. Still has the same codes. It'll barely move out of the driveway. Please help

 

[Kevin D Pem]

Type those codes into the browser search window.

 

[Chris2006]

Type those codes into the browser search window.

Yup. Did that. Coil voltage issues cylinders 2, 3, 4, and 5. Changed the plugs and the coils. Still having the same issue. Check the connection. Checked the wiring harness. Checked the ground. Replaced those coils with another set of new ones. Same codes. Other issues may be the PCM shorted out. Not sure....I don't have a way to test it. It still starts up. Idles fun.....not showing any misfires for those cylinders when it's running. Zero power when it's in drive.

 

[Kevin D Pem]

Check actual wires for damage. From PCM to coils. Just like in the days of points and distributors, the PCM discharges a capacitor to create the spark. Voltage is present at the coils, but there is a poor connection.

If the PCM is registering low voltage, this is 8 wiring issue.

Enough spark to idle, but not enough power under load. Those spark plugs are not doing their job, that's several cylinders of power that is not only not there, but acting as a load on the system.

 

[Kevin D Pem]

The expensive lesson was you replaced before you checked the simple stuff first.

 

[Chris2006]

Check actual wires for damage. From PCM to coils. Just like in the days of points and distributors, the PCM discharges a capacitor to create the spark. Voltage is present at the coils, but there is a poor connection.

If the PCM is registering low voltage, this is 8 wiring issue.

Enough spark to idle, but not enough power under load. Those spark plugs are not doing their job, that's several cylinders of power that is not only not there, but acting as a load on the system.

I've checked it all. Rechecking everything again. Wires and grounds. Bank 1 is cylinders 1-5. The problem is cylinder 1 doesn't have any issues. No codes. 2-5 are the problem. Which is weird unless it's the wiring for those individual cylinders but I been thru the harness. No damage or moisture. Everything had been cleared. Usually a bad ground would effect all the cylinders in the bank. Or those circuits in the PCM failed for those cylinders. But I'm going thru all of it starting from the battery.

 

[Kevin D Pem]

You should be able to find the resistance for the coils, or because you put new ones in just log the resistance. This would not be ground problem. You should have a voltage at the coils.

That voltage should present itself to the PCM.
In the PCM a capacitor is charged by that voltage. It is discharged by a FET, that creates a flyback voltage in the coil. That lower voltage lowers the potential spark,in turn the burn.

What I am saying is that wiring issue can be from the voltage source all the way to the PCM. any resistance/ connection All the way up to the PCM can be the problem.

You may need to use a resistor to load test the faulty circuits/wires. To find the bad connection, if a visual can't expose the fault.

Another option is to use an IR camera to look for hot spots in the wire harness.

 

[Chris2006]