Jeep still surges

GaryMB · #1 (**permalink**) 05-12-2005, 12:36 AM

Well i replaced the fuel pump and fuel filter in my cj7 and it still has trouble with engine power fluctuating. It is worse when it's cold; I can't even let the clutch out w/o killing the jeep if I have just started it up after letting it sit for a couple hours. After that, it just has trouble with throttle response (usually between 1000 and 2000 rpm), where it will not respond at all to the throttle, or will respond poorly. It occasionally drives fine, but usually lurches/hops when I'm accelerating. Any Ideas? I recently installed an hei and motorcraft carb, but the jeep ran pretty well when I first installed them.

geopig · #2 (**permalink**) 05-14-2005, 05:23 PM

I was having power surges and running rich with my 91 YJ and the issue was the fuel pressure regulator. It's easy to spot a problem with that just hook up a pressure gauge to the fuel rail and see if you have too high/low or fluctuating pressure. Put in the new regulator 2 weeks ago and was good to go. You may want to check your plugs afterwards (and 02 sensor) if you indeed have been running rich.

lah2420 · #3 (**permalink**) 05-15-2005, 11:33 AM

The 84 won't have a fuel rail. That's fuel injection equipment only. I know you're probably tired of the question, but are you positive there are no vacuum leaks? Also, check the tightness of your carb. It could also POSSIBLY be a leak in the intake manifold gasket or a loose bolt on the manifold. They require a specific torque that is different on some bolts. If you just crank them down, the gaskets will be damaged. After reinstalling my motor, it took about 3 or 4 times to get the bolts torqued right and then I found a bad gasket was on it. I tried a Motorcraft and couldn't get it to idle right. After 2 weeks of working with it, I went back to the Weber. I didn't have problems with it surging though.