BroncoII4x4.com

1988 fbII 2.9 efi a4ld auto transmission 4X4 all stock.. as a daily driver when i go up hills on paved roads out of 4X4 im loosing power and no matter how much gas i give it i keep loosing speed and there is a rattling sound coming from the engine possably a bering. any one know what the problem might be i have been all over the engine and transmission and cant find any external or vacume problems and trans fluid is at full line ,,transfer case is full also,,,, HELP

gary65

This is just a quick thought . . .

The rattling noise associated with power loss sounds like "pinging" or pre-ignition. A sign of timing being off, advance timing not happening properly, bad gas, bad plugs etc.. Also, I think your engine has a special vibration sensor that advances the timing if pre-ignition occurs. At 19 years old, it's probably suspect too.

I would again check all vacuum lines and connections, including replacing the PVC valve, replace the spark plugs (put in Autolite Double Platinums) and check the timing.

CraigK