motor problem

Hey guys, I have an 89 xj with a 5.5" lift 33" tires and stock 3.55 gears. My problem is, I'm getting gas into my oil and oil blowing out to my air filter and I checked my mileage, and I'm getting 4 mpg. Any ideas to what would cause this. I need help bad. Thanks.

Better check compression. With that much blow-by I'd suspect a bad piston.

Hallo. Better is to do a leak down test , but first clean the CCV system .
Put 100 PSI air into the cilinder and listen on the oilcap opening.:listenmus




'92XJwim

Ok cool, thanks guys. I'm gonna do the compression check tomorrow and see what I have. I will also do the leak down test too. Thank you.

STOP.

First, oil in the air filter is USUALLY a clogged CCV system. Inspect/clean/repair.

Second, fuel in your oil you should test your fuel pressure and inspect test your injectors.

If your engine was in such bad shape to deliver only 4 MPG, I doubt it would have enough compression to even run.

How do you check the injectors? I'm not sure how to do it. And I has a new pcv valve that's only a month old.

What engine?

Its the 4.0

Ok, so you modded it to have a PCV valve, as all 4.0s came from the factory equipped with CCV systems.

Got any pictures of your mods?

Have you tested the fuel pressure?

No mod, I guess I just changed from gromet and tube to the air box. Sorry. I don't know a whole lot about it yet. And the rear gromet on the valve cover and vaccum line to the manifold are now all clean, they were clogged. And I haven't checked the fuel pressure yet. I'm gonna do the compession test tomorrow. I don't where all the gas is coming from. I think possible a injector is spraying all the time and flooding out one cylinder and that's where the gas is coming from. I'm not sure though, that's why I'm asking so many questions. Thank you for the help.

Ok.

Just to step through it, the front of the valve cover is a fresh filtered air intake. Sometimes the "J" hose off the airbox will rot internally so that it can actually collapse and cut off the air to the v/c. The rear of the valve cover has a metered port, then the vacuum line to the intake manifold port. I use a wire at each oil change to make sure the orifices are open.

You will need to clean things up and just keep checking to see if that has got the oil in the filter under control.

Your compression readings, with the rings and cylinder walls washed down with fuel, might read a little low, but post the results.

Your fuel pressure should be a good 30-31 psi with the vacuum line attached to the pressure regulator at the front of the fuel rail, and it should be about 39 psi without the vacuum to the regulator.

BTW--what injectors are you running? If they are the original Bosch injectors made with the two piece bodies, plastic and metal crimped together, GET RID OF THEM! They are an engine fire waiting to happen. If you need to replace the injectors you can use Ford 19 lb orange-top injectors, and you can get them at the salvage yards for about $30 for a set, they were used in 3.8 liter and up Ford engines including the V8s in the F350 vans. They are a one-piece body, have a 4-hole nozzle instead of the single nozzle, and you can use the Ford o-ring seals, usually cheaper.

Testing the injectors should be left to a shop with the proper equipment. If you have the crummy original two-piece injectors don't bother with them, they aren't worth testing.

Ok sounds good, I will post the results of the comp test and I will check when its light again what injectors they are. Thanks for the info on the ford injectors, I will be getting them next payday. Thanks.

The comp test didn't happen, didn't have the right end to put in the head. So I will make it happen soon. After every thing I have bought for it I'm out of money. Just picked a re adjustable track bar so that's what is going on it today.