New-ish guy----big problem
Thread Starter
|
New User
Joined: Apr 2009
Posts: 10
Likes: 0
New-ish guy----big problem
Guys I was on here for a few years when I had my Ranger so it's changed here and is like a totally new site. I am currently banging my head trying to figure out a stalling condition on a 1990 F-150 with a 5.8L and 2wd. Starts up fine and fuel pressure is good, battery and charging system are good (charging @14.5 vdc) and grounds are good. I took the IAC and the EGR off to clean. I did a spark plug, plug wire, cap&rotor tune-up on it and changed the fuel filter. New air filter too. Truck starts and hovers @ 600 rpm, stumbles a little but catches itself, and then will die within a minute or so. Drives great and so far hasn't stalled in gear (but I've been told it does). Repaired a few vacuum lines that run along the passenger side near the exhaust manifold. I'm getting 12v at both the EGR and the IAC and both grounds there are good too. Scratching my head...and losing hair over this. Any input welcome to save this old gem.
Fleet Owner
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
You should not have a ground until you have a warm engine and are at hi-way speed but not WOT. Never at idle or with the engine not running.
Thread Starter
|
New User
Joined: Apr 2009
Posts: 10
Likes: 0
The EGR solenoid is a three wire and you are saying that ko/eo (key on/engine off) I should get 12v but no ground through the solenoid wiring harness? What are the three wires? Should I get 12v and also a 5v for reference? Out on it right now..
Fleet Owner
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
If you are talking about the EVP sensor on top of the EGR valve it has three wires, a ground, +5 VDC and a signal return wire.
Thread Starter
|
New User
Joined: Apr 2009
Posts: 10
Likes: 0
Trending Topics
Posting Guru
Joined: Jul 2004
Posts: 2,244
Likes: 2
From: Cottage Grove, WI
could be a shot fuel pump too. Able to prime the system & start, but does not stay running after prime
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Thread Starter
|
New User
Joined: Apr 2009
Posts: 10
Likes: 0
Just probed the red wire and got 12v (assuming I'm in the right spot). Is the EGR solenoid just in front of and to the passenger side of the coil? I'm tracing the two vacuum lines that go from it (green and red) along with a red wire and a green wire.
Thread Starter
|
New User
Joined: Apr 2009
Posts: 10
Likes: 0
This thing runs great outside of the idle issue. The trucks condition is overall excellent and has lead a good life (mechanic owned). 332k miles are taking their toll.
Fleet Owner
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
By the way that 12 volt red wire is common to all solenoids, fuel injectors and the fuel pump relay, it comes from the EEC power relay.
Fleet Owner
Joined: Aug 2005
Posts: 23,667
Likes: 301
From: Easton,Ks
If the EGR valve was open at idle you would have idle problems.
Sounds like yours is working right.