5.4 engine starts and dies instantly after start up - Diesel Forum

fedexpsd · 12-07-2007, 08:24 AM

2000 Excursion with 5.4 with appx 100k miles. Sometimes on engine start up the engine starts and then dies. When it does this the only way to keep the engine running is to apply some throttle to keep it at a high idle and after about 10 seconds the engine will rev up without moving the throttle and the truck will then operate perfectly. Very intermittent. There are no indicator lights, and no codes present.

NEG297F · 12-07-2007, 01:31 PM

sounds like a vacuum leak

Ugly-Jeep-Truck · 12-07-2007, 02:01 PM

Or a stuck idle air control motor, if it even has one. When my Mustang would do this that was the culprit.

DaveV10 · 12-08-2007, 02:28 AM

! second vote for the IAC motor/valve being stuck/dirty. Mom's old explorer needed it cleaned about once a year or so.

Lightningfast01 · 12-23-2007, 11:50 PM

Pull and clean, tap, or replace the IAC motor and look for an vacuum leak around the PCV elbows as they crack and rot with age.

fxdwgi · 12-25-2007, 11:20 PM

Stuck IAC....

Mastertech · 12-26-2007, 09:43 PM

My vote is for a stuck IAC. Those things have kept me busy over the years.