V8-X
Well-Known Member
- Joined
- November 6, 2002
- Messages
- 119
- Reaction score
- 0
- City, State
- Edgewater, CO
- Year, Model & Trim Level
- 02 F-150 S.C. Lariat FX4
1999-X-5.0/302-AWD-4R70W
No CEL, No flashing O/D light, No ABS light and No codes stored in ECU.
I am having a general lack of power on acceleration at all speeds, which becomes more noticable and creates a vibration/noise through the floorboard & gas pedal.
When between 30-45mph with OD off and 40-55mph OD on, is when the vibrations start to occur. This is also right after the 3rd gear change or when the TC locks up. Once this gear change/TC lock up occurs, the exhaust or driveline gets a deep hum tone to it. If I coast, the deep tone goes away. Every time I give it gas within the above scenerio the deep tone comes back and stays until I let off the gas. When the RPMs are around 1500 during the above scenerio, I get a slight grinding or moaning sound from the driveline. It sounds sort of like a Manual Trans trying to pick up speed in 3rd gear when it should be in 2nd gear.
When ever you let off the gas (to coast or stop), it feels and sounds like an excesive engine brake. You get a little tug backwards, and the X starts to slow down really quick. Not like a normal Auto Trans, which will coast you to a stop. It feels as though something is pulling you in the other direction to slow you down. Also when coasting next to a wall, I here a slight grinding sound (like metal to metal contact) coming from underneath the X. The driveline was checked, and the shop stated the only problem they noticed was a little slack in the T-Case. What would slack in the T-Case mean, and how would this effect the X?
Trans, T-Case, & front Diff fluid have been changed. EGR, TPS, FPR, IAC, all O2's, Fuel Filter, all Plugs & Wires, and both Ing. Coils replaced. MAS/MAF (however you refer to it), has been cleaned twice. None of the above suggestions have corrected this problem.
It does seem that the problem gets worse the longer the X is running. Seems to be heat related, but not completely. As the problem is there on cold starts, but just gets worse as it warms up.
Now when the problem is at it's worst, I get a lot of noise from the Fuel Injectors firing and the Intake sounds like its swallowing a ton of air. I can give the X 1/2 throttle and the Injectors and Intake start pumping like crazy, but the transfer of power to the wheels isn't there. When I accelerate the Injectors, Intake and engine seem like their increasing speed, but it takes 2-5 seconds for the X to realize I've given it more gas and then starts to pick up speed. Now when it does start to pick up speed, the X seems to labor and the pick up in speed is very minimal.
Hopefully someone or everyone can give me some advice on what to check, and maybe how. I have a Haynes book for the X, so hopefully I can find procedures for what you suggest. The problem is almost a year old (started July 2002), and I haven't found a shop that can find the problem, as you can tell by the parts I have replaced. (2 Ford Service Centers, 1 Transmission shop, 1 supposed Ford Specialist and 3 Independent shops) Any and all suggestions are welcome, I just want to have the 302 power back that I originally purchased the X for , and to fix the Vibration problem. I don't know if the lack of power and vibration are related problems, but they both came about at the same time. All started when the #4 plug went bad, tripped the CEL, Ford checked & replaced, CEL has never come back on since then.
Thanks everyone!
No CEL, No flashing O/D light, No ABS light and No codes stored in ECU.
I am having a general lack of power on acceleration at all speeds, which becomes more noticable and creates a vibration/noise through the floorboard & gas pedal.
When between 30-45mph with OD off and 40-55mph OD on, is when the vibrations start to occur. This is also right after the 3rd gear change or when the TC locks up. Once this gear change/TC lock up occurs, the exhaust or driveline gets a deep hum tone to it. If I coast, the deep tone goes away. Every time I give it gas within the above scenerio the deep tone comes back and stays until I let off the gas. When the RPMs are around 1500 during the above scenerio, I get a slight grinding or moaning sound from the driveline. It sounds sort of like a Manual Trans trying to pick up speed in 3rd gear when it should be in 2nd gear.
When ever you let off the gas (to coast or stop), it feels and sounds like an excesive engine brake. You get a little tug backwards, and the X starts to slow down really quick. Not like a normal Auto Trans, which will coast you to a stop. It feels as though something is pulling you in the other direction to slow you down. Also when coasting next to a wall, I here a slight grinding sound (like metal to metal contact) coming from underneath the X. The driveline was checked, and the shop stated the only problem they noticed was a little slack in the T-Case. What would slack in the T-Case mean, and how would this effect the X?
Trans, T-Case, & front Diff fluid have been changed. EGR, TPS, FPR, IAC, all O2's, Fuel Filter, all Plugs & Wires, and both Ing. Coils replaced. MAS/MAF (however you refer to it), has been cleaned twice. None of the above suggestions have corrected this problem.
It does seem that the problem gets worse the longer the X is running. Seems to be heat related, but not completely. As the problem is there on cold starts, but just gets worse as it warms up.
Now when the problem is at it's worst, I get a lot of noise from the Fuel Injectors firing and the Intake sounds like its swallowing a ton of air. I can give the X 1/2 throttle and the Injectors and Intake start pumping like crazy, but the transfer of power to the wheels isn't there. When I accelerate the Injectors, Intake and engine seem like their increasing speed, but it takes 2-5 seconds for the X to realize I've given it more gas and then starts to pick up speed. Now when it does start to pick up speed, the X seems to labor and the pick up in speed is very minimal.
Hopefully someone or everyone can give me some advice on what to check, and maybe how. I have a Haynes book for the X, so hopefully I can find procedures for what you suggest. The problem is almost a year old (started July 2002), and I haven't found a shop that can find the problem, as you can tell by the parts I have replaced. (2 Ford Service Centers, 1 Transmission shop, 1 supposed Ford Specialist and 3 Independent shops) Any and all suggestions are welcome, I just want to have the 302 power back that I originally purchased the X for , and to fix the Vibration problem. I don't know if the lack of power and vibration are related problems, but they both came about at the same time. All started when the #4 plug went bad, tripped the CEL, Ford checked & replaced, CEL has never come back on since then.
Thanks everyone!
