Good morning all. I've searched and asked on other sites about this problem. When I go to start my 03 s40 w/90000 miles 1st time after sitting for 12 or so hours it will fire then die right out. If I give it gas to about 1500rpm it stays running and after about a minute it will run on its own. It will then high idle for a few mins. and act normal. After the initial trouble it will start fine the rest of the day. No codes, no misfires or anything. It has a new(at 55000 miles) dealer installed MAF and FPR It's not acting like it did then. Suggestions so far are clean idle air and MAF but 1 mechanic suggested a MAP sensor, but he thought if that was the problem it should throw a code. Anyway I appreciate any feedback and input. Thanks

 

Yeah, there are about 5 sensors that help control/monitor air:fuel in the car and the MAP could definitely be a source. I would also take a look at the IAC. If it is sticking in either position it could be causing your car to stall/run rough until it is 'warm'. Both of these are not cheap parts, so I would recommend that you take off the IAC and use some electrical parts cleaner or tuner cleaner to help remove some of the build up. It may be a losing battle, but it only takes 2 minutes to remove it and $7 for the cleaner. Much cheaper then the ~$150 it costs to replace the IAC. Also, you can find a new MAP at rockauto.com for about $50. So that might be a cheaper fix too.

 

Thanks Choguy. As soon as I get time I'm going to take the IAC out and clean it. I'm also going to get a resistance reading from a MAP at my friends supply house and then compare it to mine. Maybe by time I get the time it will throw a code. Thanks again.

 

Well thought things were good there for a few days as the car started each morning this week with no problems. But this AM went out to start it and had the same problem of no idle for a minute or so. The only common denominator it appears is wet weather. All last week it was clear and dry and the morning it's raining and the problem is back.(when the problem started it had rained for 3 or 4 days). Oh well, back to square 1.