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valve cover pcv valve?

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Old Nov 30, 2013 | 05:36 PM
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Default valve cover pcv valve?

Hi guys! I just got my second ever xj today. Its an 89 cherokee pioneer with 130k and a nice poo/bronze/gold color. Ive named it The golden heap! It was 650 dollars and has numerous problems. First off i thought it had a death wobble but it was just a bad tire so i put the studded slightly smaller spare on...lol Good enough for now!

Biggest problem is the idle changes while running. Enough to nearly stall out. The first thing i noticed is the pcv on top of the valve cover is missing and hte hose is just mangled. Would that cause this issue other than spraying oil all over the engine? If so can someone find the part on autozone for me?
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Old Nov 30, 2013 | 06:11 PM
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Just for fun you should read the thread "Where is the pcv valve located?" last posted on 11-25-13
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Old Nov 30, 2013 | 06:52 PM
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On these they call the deal that provides Positive Crankcase Ventilation a CCV valve. (go figure) It goes on the rear of the valve cover, then the tube to the intake manifold sucks on it. The large front tube needs to be free to vent to the air cleaner.

If you scroll down from the link in my signature there are some Napa part #'s for that stuff in there somewhere. (on top is a link to Cruisers info on your geep, it's in there also) You might want to clean your IAT and TB..

Does it cycle every 20-30 sec? (slow down, almost die, surge, then repeat?) That would be a dead 02 sensor.
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Old Nov 30, 2013 | 08:51 PM
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Everything you need to know about your new Jeep, and how to fix a lot of the problems: https://www.cherokeeforum.com/f51/cruiser54s-mostly-renix-tips-153657/
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Old Nov 30, 2013 | 09:05 PM
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Renix Vacuum Harnesses
The vacuum harness that attaches to the front of the valve cover and includes the grommet/fitting, and is called the front harness, is Napa part number BK 715-1367
 
 
The vacuum harness that is closest to the air cleaner, EGR etc, and is called the rear harness, is Napa part number BK-715-1366.
 
 
The tube from the rear of the valve cover to the intake manifold is part number 715-1365.

The grommet alone for the rear is a 42088 Dorman.
 
 
Revised 09-11-2012
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Old Nov 30, 2013 | 09:24 PM
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OK, I edited the info in my sig;

Renix Vacuum Harnesses/CCV stuff.
The vacuum harness that attaches to the front of the valve cover and includes the grommet/fitting is Napa part number BK 715-1367
The vacuum harness that is closest to the air cleaner, EGR etc, and is called the rear harness, is Napa part number BK-715-1366.
The tube from the rear of the valve cover to the intake manifold is part number 715-1365.
The grommet alone for the rear is a 42088 Dorman
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Old Nov 30, 2013 | 09:31 PM
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Originally Posted by DFlintstone
On these they call the deal that provides Positive Crankcase Ventilation a CCV valve. (go figure) It goes on the rear of the valve cover, then the tube to the intake manifold sucks on it. The large front tube needs to be free to vent to the air cleaner.

If you scroll down from the link in my signature there are some Napa part #'s for that stuff in there somewhere. (on top is a link to Cruisers info on your geep, it's in there also) You might want to clean your IAT and TB..

Does it cycle every 20-30 sec? (slow down, almost die, surge, then repeat?) That would be a dead 02 sensor.
Theres a valve on the top of my valve cover that is snapped off and the hose shredded. Not on the back. The hose went tot he back of the air filter box.

Thanks for the suggestion. Tomorrow is pick n pull day at the junk yard. Just trying to come up with parts list.

It does seem like that is the issue where it cycles through idling. High and low.

Its also heaitng oddly. While driving the temperature went up nearly to redline. At a stoplight the temperature dropped. I was told there is a coolant leak from the water pump but i didnt see anything and i think its got straight water in it at the moment.
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Old Nov 30, 2013 | 09:46 PM
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The elbows on top of the valve cover are just empty elbows, no PCV valves at all. You won't find any CCV fittings at the JY worth pulling. They will explode in your hand when you try to remove them as the plastic becomes brittle with years of heat cycling.

Is your temp accurate? XJs made prior to 1997 have a separate sensor that drives the dash gauge and it notoriously goes out. It's installed at the rear of the block. You need something like an IR thermometer pointed at the thermostat housing to find the real temperature.

Straight water in Oregon?! You wanna keep driving that thing?? :O
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Old Nov 30, 2013 | 09:46 PM
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Those nappa part numbers arent pulling up anything for me.

This is what i found for vaccum harness though.
http://www.napaonline.com/Catalog/Ca...367_0390168068
http://www.napaonline.com/Catalog/Ca...366_0390168066

Annoying that you have to buy the whole darn thing but if one of my vaccum lines is this jacked up they are all probably due for replacement. Should i get both of these?
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Old Nov 30, 2013 | 09:48 PM
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Lol im in portland. We dont get below freezing too often. But part of my plan is a good flush system. Is this radiator system much different from a 92? I didnt realize i was getting a renix era one and im trying to understand the differences.
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Old Nov 30, 2013 | 09:57 PM
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Well...the CCV valve belongs on the rear, and the front was just an "L". That front will make a mess if it's not routed right. A free 1/2 inch tube to the air cleaner.

You want a 50/50 mix of coolant asap. The best way to drain it is to remove the E-fan with it's two little screws and pull the lower hose. The water pump has a "weep hole" where it will leak when the seal goes. Might be intermittent at first.....

Check out Cruisers stuff, check your sensor ground resistance and clean things up, (grounds). You can endlessly chase your own tail if that isn't handled.

You might save the 02 stuff for after you handle more imitate stuff. Your mileage will suck in the meantime. Idle cycleing every 20-30 secs?

It may or may not be tough to find that fitting that is not brittle and just breaks.

One more thing;

There is a brittle little tube. It comes out of a rubber plug, low on the engine side of the throttle body. It runs back to the firewall, then up to your MAP sensor sort of high up there near center on the firewall. CRUCIAL!! The MAP will tell the ECU to dump fuel with less/no vacuum. Any crack or blockage and it will be pig-rich.
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Old Nov 30, 2013 | 10:00 PM
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Originally Posted by salad
The elbows on top of the valve cover are just empty elbows,
???the Renix CCV valve fits in the rear grommet IIRC.....Mine is buried in silicone!
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Old Nov 30, 2013 | 10:01 PM
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I wish you guys were in oregon =P Well first step is im gonna go to my grandpas and try to find my manual. Gonna get an ignition cylinder and some door lock cylinders because the jeep can be started without a key... Junk yard grabs ive got so far will be rear right hand bumper cover and tail light cover and drivers seat belt buckle.
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Old Nov 30, 2013 | 10:04 PM
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Originally Posted by Crimmy
I didnt realize i was getting a renix era one and im trying to understand the differences.
Renix ECU stores no codes and has no check engine light. You need a digital volt meter to see what it's doing, it ain't gonna tell you!
Renix cooling system is a "closed" system. That is an expansion bottle, should be left 1/2 empty so the air can compress.
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Old Nov 30, 2013 | 10:09 PM
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So can i cut the heater hose and put a T in there and hook a garden hose up and back flush out through that lower radiator hose? There is no radiator cap then?
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