Intermittent stumble above idle
Thread Starter
|
New User
Joined: Aug 2019
Posts: 2
Likes: 0
From: San Jose
Intermittent stumble above idle
Hello,
this is a 2003 F150 XL with 4.2 L V6, very basic truck. Only 90 000 miles on it.
For some time it’s had a intermittent problem, rigtafter start or after a couple of blocks the engine won’t rev up higher than app 1000 RPM.
Idle is fine 9 times out of 10, but when I hit the pedal lightly, the engine is dying. When I lift the pedal, Idle is smooth and steady 650 RPM.
It’s coasting on idle, but accelerating makes it stumble. This may happen a few times or take a few minutes. I made a 1000 mile trip and had no symptoms for two weeks and then it came back. This week getting going on Monday and Friday was bad, other days were just fine.
- No codes, no check engine light ON
- Ihave a basic OBDII reader, but it doesn’t show anything special
- no mis/backfiring
- new fuel and air filter
- never had the injectors cleaned, but used sometimes cleaner in the fuel
- quite similar to topic “hesitation, surge, stumble over 1500 RPM”
Any comment is welcome,
Thanks.
this is a 2003 F150 XL with 4.2 L V6, very basic truck. Only 90 000 miles on it.
For some time it’s had a intermittent problem, rigtafter start or after a couple of blocks the engine won’t rev up higher than app 1000 RPM.
Idle is fine 9 times out of 10, but when I hit the pedal lightly, the engine is dying. When I lift the pedal, Idle is smooth and steady 650 RPM.
It’s coasting on idle, but accelerating makes it stumble. This may happen a few times or take a few minutes. I made a 1000 mile trip and had no symptoms for two weeks and then it came back. This week getting going on Monday and Friday was bad, other days were just fine.
- No codes, no check engine light ON
- Ihave a basic OBDII reader, but it doesn’t show anything special
- no mis/backfiring
- new fuel and air filter
- never had the injectors cleaned, but used sometimes cleaner in the fuel
- quite similar to topic “hesitation, surge, stumble over 1500 RPM”
Any comment is welcome,
Thanks.
Thread Starter
|
New User
Joined: Aug 2019
Posts: 2
Likes: 0
From: San Jose
Hello - got this mystery solved aye the dealership. It was after all a sticky EGR valve. It didn’t show up in the codes, because there is no feedback loop whether the valve is open or not.
It took some time for the shop to figure it out. Not like in the eighties, when most of the running problems were caused by the then new emissions gear.
We’re back in business, Thanks.
It took some time for the shop to figure it out. Not like in the eighties, when most of the running problems were caused by the then new emissions gear.
We’re back in business, Thanks.
Thread
Thread Starter
Forum
Replies
Last Post
91 Super Duty
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
10
Aug 24, 2011 02:35 PM
aballard
Explorer, Sport Trac, Mountaineer & Aviator
1
Feb 3, 2006 07:19 AM
