In the middle of my 2.5 hour interstate highway drive (about 70mph) my engine starts running weird. All of a sudden it's hard to hold a steady speed because the engine wants to caugh and sputter... BUT if I push the pedal to the floor, the enine would accelerate seemingly with MORE power than normal. I was accelerating up hills with my 4.2L in 5th gear like I never have before, but as soon as I back off the gas it felt like I was hitting the brakes.
When I get off the highway I stop at the end of the ramp and the engine is idling at 2000 RPMs. Won't tap down or anything. I start moving again and it still feels like there's no power unless I'm flooring it. After shifting up to 3rd I stop at another stop sign... this time as soon as the clutch goes in the engine dies completely. Eventually it starts again but it's idling low and rough at like 400 RPMs.
Again I accelerate to third and it dies immediatly at the next stop. After restarting it's again idling low and rough. I rev. the engine a bunch of times and afterwards it's idling normally - smooth 700RPMs or so.
After this it's driving normally on a 45mph road with stoplights every 5-10 minutes. At some stops though it idles normally, others low and rough again.
'87 YJ Laredo
- 4.0L, AX-15, NP231, 4.10s: 3.5" BDS, 31" Muds
- Donated drive train to the YJ, Parted out the rest
- Buick 225 V6: Painless Wiring Harness, Warn Overdrive & Hubs, 2" Lift, 31" Muds