[4th Gen : 01-07]: Misfire detected in multiple cylinders
#1
Misfire detected in multiple cylinders
Hi all,
I have a 2005 Grand Caravan 3.8L. The van started acting up sometime ago specially when trying to accelerate or driving uphill and the check engine came up with P300 code. I replaced the spark plugs and the wires and the code never came back and it was good for about a week but then it started acting up again like before! However, this time with no check engine/codes.
I found a number old threads and webpages with similar problem but with different resolutions from simply replacing a spark plug to changing the manifold gasket or a broken valve spring!
So what are the things that I can check/change to fix/diagnose the problem before needing a real mechanic?
I thought about replacing the ignition coil pack (~$30) but wanted to ask first before wasting money.
I have a 2005 Grand Caravan 3.8L. The van started acting up sometime ago specially when trying to accelerate or driving uphill and the check engine came up with P300 code. I replaced the spark plugs and the wires and the code never came back and it was good for about a week but then it started acting up again like before! However, this time with no check engine/codes.
I found a number old threads and webpages with similar problem but with different resolutions from simply replacing a spark plug to changing the manifold gasket or a broken valve spring!
So what are the things that I can check/change to fix/diagnose the problem before needing a real mechanic?
I thought about replacing the ignition coil pack (~$30) but wanted to ask first before wasting money.
Last edited by fduraibi; 03-16-2015 at 11:50 AM.
#2
So exactly how long ago did the poor running start? If enough raw gas gets sent down into the cat as a result of misfiring, it eventually will get trashed out. You could test for a plugged cat by temporarily pulling the upstream O2 sensor to see if it runs better with some of the exhaust going out the O2 sensor port.
#3
So exactly how long ago did the poor running start? If enough raw gas gets sent down into the cat as a result of misfiring, it eventually will get trashed out. You could test for a plugged cat by temporarily pulling the upstream O2 sensor to see if it runs better with some of the exhaust going out the O2 sensor port.
But I am going to check the O2 sensor and let you know the result.
BTW, using a simple OBD2 reader the cat passes the test and I don't get any error codes.