Cold rough idle, misfires until warm
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Joined: May 2011
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Well... my problem was all caused by the crankshaft sensor. The first part I replaced because I thought that might be the problem and come to find out I got a bad one from the parts place. Just glad this nightmare is over.
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Joined: Jul 2020
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Ok I have a bit of a problem that just came up. 99 Ram 1500 3.9L
Yesterday morning I got in the truck and it was running bad. Misfiring, popping through the exhaust and idling real rough. After about 10-15 minutes it smoothed out and ran fine the rest of the day. So I immediately thought cap & rotor (even though I had replaced them both not more than 1 1/2 years ago). Yesterday evening I replaced both and asked the wife how the truck was doing and she said fine. I took it out for a drive afterwards and no problems at all. This morning I start the truck up and it is doing the exact same thing. Any ideas where to start looking next?
Yesterday morning I got in the truck and it was running bad. Misfiring, popping through the exhaust and idling real rough. After about 10-15 minutes it smoothed out and ran fine the rest of the day. So I immediately thought cap & rotor (even though I had replaced them both not more than 1 1/2 years ago). Yesterday evening I replaced both and asked the wife how the truck was doing and she said fine. I took it out for a drive afterwards and no problems at all. This morning I start the truck up and it is doing the exact same thing. Any ideas where to start looking next?
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Joined: Jul 2020
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Fast way to check for plenum leak is to take off the breather hose going to you air cleaner over the intake....When running at idle a plenum leak will cause a huge amount of vacuum at the end of that hose. Normally there is only slight detectable vacuum there. You will know what I am talking about if you check it..it is very obvious.