2004 3.0L engine issues (surging)
Thread Starter
|
Senior User
Joined: Aug 2003
Posts: 107
Likes: 0
From: Central TEXAS
2004 3.0L engine issues (surging)
For the last couple of weeks I have been getting an intermittent (about 6 times now) 301 engine code (misfire cyl #1) and the truck surges (especially when bogged down) sometimes slight and sometimes bad. Sometimes with an error code, but most of the time without. Once or twice I also got a air/fuel circuit code. Once I even got a 312 engine code (cyl #12 ??? misfire). Once I got a code that had something to do with the transmission. I'm thinking that it is a cyl #1 injector or coil issue, but it could be the mass air sensor also. What would you suggest I try replacing first? I have already replaced the plugs, wires, fuel filter, and air filter. The plugs were whitish and seemd a little lean, but not too bad. #1 cyl didn't look any different than the others. Fuel mileage has not seemed to drop. Taking off and until I hit about 2000 rpm it surges. If it is just one cylinder messing up then why would it surge so badly? Could it be that the computer is only recognizing it on cyl #1, but it is actually happening in other cyl also? What is really weird is when it is idling rough and surging bad I usually don't get any engine codes.
thanks
stephen
thanks
stephen
Post Fiend
Joined: Jan 2003
Posts: 9,748
Likes: 16
From: Connecticut
Sounds like you've adressed the basics.
If it's not an injector issue (and I doubt it is), then here's something you have to consider (unfortunately): Ford TSB 05-26-3
If it's not an injector issue (and I doubt it is), then here's something you have to consider (unfortunately): Ford TSB 05-26-3
Thread Starter
|
Senior User
Joined: Aug 2003
Posts: 107
Likes: 0
From: Central TEXAS
any other ideas, because I sure hope its not the exh valve issues stated above. If it is I will just run it til it dies and then redo the heads myself. hmm... maybe a port job will give it a little more power?
Thread Starter
|
Senior User
Joined: Aug 2003
Posts: 107
Likes: 0
From: Central TEXAS
I have been thinking about that service bulletin on the exh valve issue and don't know if that is the problem. About half the time it runs perfect and 1/4 the time it runs okay (not too bad) and 1/4 of the time it is bad. If it is an exh valve seat issue wouldn't it be doing this all of the time? I also noticed that a couple of times the "check gauge" light flashed very quickly. It took me a while to figure out which light it was because it would flash very quickly. What would cause this? All the gauges are in their normal range.
Former ******
Joined: Nov 2004
Posts: 4,901
Likes: 2
From: Salt Lake City, Utah
Actually, upper intake leaks can cause it to lean out and misfire. The vacuum leak is insignificant at higher rpm, but at low RPM and idle, it can constitute a large percentage of the air in the cylinder, what can cause a misfire. You haven't specified what engine you have, but both V6s can develop intake leaks.
Logistics Pro
Joined: Jan 2002
Posts: 4,907
Likes: 39
From: suburban atlanta
I would check the EGR passages. The 3.8 has passages in the bottom of the intake directly in front of each intake valve. If some are plugged and some not, the engine will get misfires. The 3.0 I think has its EGR fed to a port on the side of the upper intake, so may not be susceptible to this problem. I would also check the MAF. Disconnect it to see if the surge goes away, but don't leave it disconnected for long. You can clean the MAF carefully if it is dirty. You can also clean the EGR system if it is plugged.
tom
tom
Trending Topics
Thread Starter
|
Senior User
Joined: Aug 2003
Posts: 107
Likes: 0
From: Central TEXAS
3.0L (in the title)
The problem was real bad at first. It ran fine since I bought the truck and just one morning out of no where it started doing this. It was real bad and even caused my truck to die out that day. When I changed plugs, filters, etc it didn't seem to help much. I forgot to mention it, but next I replaced the PCV valve and I did notice an improvement. The problem is still there intermittently, but no where near as bad as that first day. I looked at the vacuum lines and didn't see anything noticeable. Maybe I'll do a more thorough check this evening (ether). If it is a vacuum leak why would it only flag a code on cyl #1?
The problem was real bad at first. It ran fine since I bought the truck and just one morning out of no where it started doing this. It was real bad and even caused my truck to die out that day. When I changed plugs, filters, etc it didn't seem to help much. I forgot to mention it, but next I replaced the PCV valve and I did notice an improvement. The problem is still there intermittently, but no where near as bad as that first day. I looked at the vacuum lines and didn't see anything noticeable. Maybe I'll do a more thorough check this evening (ether). If it is a vacuum leak why would it only flag a code on cyl #1?
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Thread Starter
|
Senior User
Joined: Aug 2003
Posts: 107
Likes: 0
From: Central TEXAS
I unplugged the MAF and the engine ran really rough, but what was really weird is that it did not even flag a code or turn on the check engine light. I thought it should. At first I thought that the light was burned out. I don't think I could drive it with the MAf unhooked. The first check engine light came on after about 3 days of this problem.
Would an EGR system problem flag an EGR related code?
thanks for all your help so far
stephen
Would an EGR system problem flag an EGR related code?
thanks for all your help so far
stephen