Drop in Rpm on startup

[victahh1]

Hey guys,

Ever since last winter, I had an issue that whenever I would start my truck, the rpm would climb as usual, then drop suddenly and climb back up to what I consider to be a normal rpm range (1000-1500). This problem got worse when it got pretty cold like below freezing temperatures (I'm in Chicago). The rpm drop would be so bad that the truck would turn off, in order to keep the truck on I would have to hold the gas pedal to above 2000rpm. Sometimes the truck would crank but struggle turning on. This would happen both with the remote start and turning the truck on manually.

Once temps got warmer over the summer I kind of disregarded the problem, but now its winter again and I don't want to keep having this issue. I could already tell the rpm drop is getting worse when it starts. I've got the battery, alternator, and starter checked multiple times and at different locations and it all turns out to be ok. Last year I also replaced the pcv valve and the iac valve. Not sure where else to go with this.. Attached is a video where you can hear the problem. **Headphones are suggested for better sound quality**

2003 Ford Explorer AWD. 130k miles, 4.6 v8.

 

[Limited02]

My first guess would be that you need to clean the IAC valve. I had a similar problem when mine wouldn't hold idle and died when the temps were freezing. I'd have to keep on the gas and after about 15 min or so, it'd come back to life and run normal.

Do both of these and report back! https://www.explorerforum.com/forums/showthread.php?t=339793

 

[victahh1]

The IAC valve is still fairly new, I replaced it last year with an OEM Motorcraft valve. I did have a chance to clean it over the weekend as well as the MAF sensor but the problem still continues..

I had the same issue last winter, I'd have to hold the gas down to keep the truck from shutting off on me.