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CurtisP87
New Member
- Joined
- Mar 11, 2012
- Messages
- 125
- Reaction score
- 1
- Points
- 0
- Location
- Portland, OR
- Vehicle Year
- 1987
- Make / Model
- Ford
- Engine Size
- 2.9
- Transmission
- Manual
I'm having some problems with my bronco, and cant for the life of me figure out whats going on...When i turn the key it fires right up, no problems, every time. When idling its obvious that its missing on a cylinder or two. As soon as i touch the throttle, the rpms drop, motor begins shaking violently, and it sounds like its missing on three or four cylinders. Earlier today I replaced distributor cap, rotor, plugs/wires, throttle position sensor, HP fuel pump, and the filter down the line from it. Air filter is good....
I tested fuel pressure, via the schrader valve in fuel lines....35 psi at idle, and 40 psi when on throttle, despite the rough idle. This makes me think my fuel delivery is just fine (i.e. ruling out a problem with the low pressure pump or its filter), so its got to be a timing or spark issue. The plugs i took out earlier were all in o.k. shape, slightly corroded, but wet and gooey, like the engines been running rich.
Ive been doing some reading, and it almost sounds like I could have a faulty TFI. However, everything Ive been reading seems to imply that the engine should perform fine when cold, and the problems arise when it warms up, and Im having these problems when cold, the engine isnt running well enough for me to leave it on long enough to get hot.
Like i said, Im totally stumped....Has anyone else ever had similar problems?
Thanks in advance for any help or opinions!!
I tested fuel pressure, via the schrader valve in fuel lines....35 psi at idle, and 40 psi when on throttle, despite the rough idle. This makes me think my fuel delivery is just fine (i.e. ruling out a problem with the low pressure pump or its filter), so its got to be a timing or spark issue. The plugs i took out earlier were all in o.k. shape, slightly corroded, but wet and gooey, like the engines been running rich.
Ive been doing some reading, and it almost sounds like I could have a faulty TFI. However, everything Ive been reading seems to imply that the engine should perform fine when cold, and the problems arise when it warms up, and Im having these problems when cold, the engine isnt running well enough for me to leave it on long enough to get hot.
Like i said, Im totally stumped....Has anyone else ever had similar problems?
Thanks in advance for any help or opinions!!
