I bought my Cherokee a few months back for only $300, with 230k on the odometer, and quickly learned about how bad the rear seals can leak in these things. Apparently letting the vehicle sit for several years does not do any good for the engine gaskets, either, as my head gasket only lasted about two months.

I just (finally) completed replacing the rear main seal and the head gasket (and all those that get replaced along with it) on my 1990 XJ. It started up just fine once we got it all put back together, but it is sounding like there is a HUGE air/vacuum leak coming from somewhere near the intake/exhaust manifolds, and some kind of smoke starts coming up from that area after it runs about a minute.

I have checked the torque on all the manifold bolts, and they are all as tight as I can get them. I know I need to replace a few of the smaller hoses and lines around the engine, but they don't seem to be affecting the operation or the sound of the leak.

Any help would be greatly appreciated, as I really, really need to get my daily driver back on the road!

 

Start it up stand back and lightly sprey some carb cleaner all around under the hood if there's a vacuum leak you'll find it. It'll make the motor sound like its stalling out for a second and misfireing. Also don't drench it in carb cleaner barely mist it over the motor and vacuum hoses. Also ever changed in injector o rings? I had the same problem a while back a couple of my o rings were a lil dry rotted. It caused a vacuum leak, higher rpms when idleing, and just crappy proformance.

 

And don't sprey electrical terminals, computer and other things like that try to stay away from there, are make sure they completely dry before plugging them back up. That can cause problems

 

Well I found the source of the major whistling/vacuum sucking sound. I forgot to re-install the little rubber thing in the two wholes on the inboard side of the throttle body. What the hell are those holes there for anyway???

I still have a couple of hose connections that I need to figure out. Both are on the intake manifold, one is a small connection just behind the big block where a lot of hoses connect and the other is a larger connection near the back of the intake. When I cover the rear one with a finger the engine tries to die, but nothing happens when I cover the front connection. I think these may be the cause of a really rough idle when I stop at a light?

 

Take a pic and post it what year you have? And I can prolly tell you what needs to go were

 

That's for the vacuum supply for the MAP sensor located directly behind the engine on the firewall.

 

Thank you Cruiser, I did hook up a vacuum line from that port just behind the throttle body to the MAP sensor, and the difference was almost instant, and night and day! Runs and idles MUCH better now.

Is there any way that sitting off to the side during all of the work could have damaged the power steering pump? I unbolted in from the block and left it sitting on the fender throughout most of the work, and since putting it all back together the pump all but sreams.

 

 

Hey guys my jeep will start to wobble at 45-55 mph but I notice it only start to shake when the Rpms drop to around 2000 and it doesn't shake when I step on the gas to accelerate it also shook a little while in park and while in revers . I have replaced plugs wires and distributer cap

 

You'll probably get better responses if you start your own thread, but I'll give it a shot. The wobble you feel at 45-55 mph is most likely what is (not so) affectionately referred to as death wobble. If you do a little searching, you'll find that there are many causes for death wobble, but ones that are specifically linked to speed (your 45-55 mph statement) generally have to do with your tires being out of balance and/or alignment. That's the cheapest place to start - get 'em balanced and aligned and then go from there.

 

Was the pump out in the elements? sounds like it either got rusted inside (unlikely) or is low on fluid/has an air bubble in the fluid that is causing the pump to run dry.

 

Thanks ill go ahead and get that done