1998 3.8 L P0302 error code.
Ab-normal
01-26-2006, 11:22 PM
Had my thermostat freeze closed. Caused overheated engine and coolant leak to oil. Problem was lower intake manifold gasket blown at coolant passages... NOT the heads. Anyway, had heads shave to the tight .001" tolerances at a local race engine machine shop. I had stuck ICMR butterflies and freed them. The vacum solenoids that actuate them have plastic clips that broke, but don't these only close at less than 750 RPM? So, I disconnected them and leave them open all the time. They were like that before anyway and I never got the P0302 "Cylinder #2 misfire" code before all the overheating problem started.
I did clean everything during re-assembly, but not the EGR ports. I have double-checked all plug wires, which were replaced during the head-gasket fix as well since it seemed easier to do at the time and I had original "Ford" plug wires with 148K miles. Plugs are also Motorcraft, the kind that can be used for both left and right banks. These were replaced about three months ago, just before the engine overheated. Again, I have only got the cylinder 2 misfire code after I did this work to fix the overheating problem.
The water and oil mixing created a sludge all inside the engine I liken to thick chocolate pudding. It was everywhere. It was about 20 degrees F outside when this happened. The race mechanic who did my heads suggested putting one of those bullet-type heaters under the engine to warm up the sludge and let it drip til it quit dripping and then drain/replace the oil and filter 3 or 4 times after getting it running to flush out what did not come out with the heater. I did that.
Engine works great now. Except I keep getting a P0302 code and engine seems to run slightly rough. I have a code scanner and clear the code, then about 20 or 30 minutes later it comes back.
I use an elm Scan box and my laptop with ProScan 2.0 software on it. I can monitor several sensors in an oscilloscope mode, but don't know what to look at to isolate the problem.
Proscan software website is here:
http://www.myscantool.com/
So you can see what I have available to troubleshoot.
I'd hate to have to take the intake apart again and clean those EGR ports. And as I've said, it did not do this before I worked on the heads.
I'm leaning towards the way the plugs go onto the coil pack.
Is there a picture that shows how to route them correctly? I had the hardest time getting the new wires to fit on and route without overlapping and the way I did it does not look as neat as the way they used to be before I changed them. I do know I have them fully seated though.
I took a timing light and clipped the pick-up coil of the light to the plug 2 wire. the light flashes very steadily. I did not do that for 20 minutes, only for 3 or 4, but.... I don't know.
Any ideas?
Thanks.
I did clean everything during re-assembly, but not the EGR ports. I have double-checked all plug wires, which were replaced during the head-gasket fix as well since it seemed easier to do at the time and I had original "Ford" plug wires with 148K miles. Plugs are also Motorcraft, the kind that can be used for both left and right banks. These were replaced about three months ago, just before the engine overheated. Again, I have only got the cylinder 2 misfire code after I did this work to fix the overheating problem.
The water and oil mixing created a sludge all inside the engine I liken to thick chocolate pudding. It was everywhere. It was about 20 degrees F outside when this happened. The race mechanic who did my heads suggested putting one of those bullet-type heaters under the engine to warm up the sludge and let it drip til it quit dripping and then drain/replace the oil and filter 3 or 4 times after getting it running to flush out what did not come out with the heater. I did that.
Engine works great now. Except I keep getting a P0302 code and engine seems to run slightly rough. I have a code scanner and clear the code, then about 20 or 30 minutes later it comes back.
I use an elm Scan box and my laptop with ProScan 2.0 software on it. I can monitor several sensors in an oscilloscope mode, but don't know what to look at to isolate the problem.
Proscan software website is here:
http://www.myscantool.com/
So you can see what I have available to troubleshoot.
I'd hate to have to take the intake apart again and clean those EGR ports. And as I've said, it did not do this before I worked on the heads.
I'm leaning towards the way the plugs go onto the coil pack.
Is there a picture that shows how to route them correctly? I had the hardest time getting the new wires to fit on and route without overlapping and the way I did it does not look as neat as the way they used to be before I changed them. I do know I have them fully seated though.
I took a timing light and clipped the pick-up coil of the light to the plug 2 wire. the light flashes very steadily. I did not do that for 20 minutes, only for 3 or 4, but.... I don't know.
Any ideas?
Thanks.
dougand3
01-27-2006, 09:31 AM
busboy4
01-27-2006, 05:22 PM
Hi Ab
I have not had the similar overheat issue that you did, but I have been dealing with the codes: P0303, P0305. I pulled the spark plugs which looked o.k., if a bit cooked - white residue as if very hot. I went ahead and pulled the intake manifold to look at the EGR ports, and 3 and 5 were clogged. Others were in various states of clogging. I had done this once before approximately two years ago. Anyway, so far it seems to have solved the problem. No codes, and no rough start and idle.
Good luck
I have not had the similar overheat issue that you did, but I have been dealing with the codes: P0303, P0305. I pulled the spark plugs which looked o.k., if a bit cooked - white residue as if very hot. I went ahead and pulled the intake manifold to look at the EGR ports, and 3 and 5 were clogged. Others were in various states of clogging. I had done this once before approximately two years ago. Anyway, so far it seems to have solved the problem. No codes, and no rough start and idle.
Good luck
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