Another Vacuum Question
#1
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Year: 1988
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Another Vacuum Question
Hello,
I replaced the vacuum harness and I'm still having a vacuum leak. I believe I've found the culprit, the vacuum tube that runs from the throttle body to the map sensor. If I spray throttle body cleaner on it where it joins the throttle body, the engine revs up. Does anyone know where to find that part? It's for an 88 XJ, and I haven't been able to find the part. Here is a pic:
https://i.imgur.com/dTjrT.jpg
Also, I found this while tracing out vacuum lines:
https://i.imgur.com/xytTf.jpg
Does that plastic plug look legit? It seems pretty custom to me. Is it something I should be concerned about?
Thanks again!
I replaced the vacuum harness and I'm still having a vacuum leak. I believe I've found the culprit, the vacuum tube that runs from the throttle body to the map sensor. If I spray throttle body cleaner on it where it joins the throttle body, the engine revs up. Does anyone know where to find that part? It's for an 88 XJ, and I haven't been able to find the part. Here is a pic:
https://i.imgur.com/dTjrT.jpg
Also, I found this while tracing out vacuum lines:
https://i.imgur.com/xytTf.jpg
Does that plastic plug look legit? It seems pretty custom to me. Is it something I should be concerned about?
Thanks again!
#2
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Year: 1991
Model: Cherokee
Engine: I-6 4.0 HO
Hello,
I replaced the vacuum harness and I'm still having a vacuum leak. I believe I've found the culprit, the vacuum tube that runs from the throttle body to the map sensor. If I spray throttle body cleaner on it where it joins the throttle body, the engine revs up. Does anyone know where to find that part? It's for an 88 XJ, and I haven't been able to find the part. Here is a pic:
https://i.imgur.com/dTjrT.jpg
Also, I found this while tracing out vacuum lines:
https://i.imgur.com/xytTf.jpg
Does that plastic plug look legit? It seems pretty custom to me. Is it something I should be concerned about?
Thanks again!
I replaced the vacuum harness and I'm still having a vacuum leak. I believe I've found the culprit, the vacuum tube that runs from the throttle body to the map sensor. If I spray throttle body cleaner on it where it joins the throttle body, the engine revs up. Does anyone know where to find that part? It's for an 88 XJ, and I haven't been able to find the part. Here is a pic:
https://i.imgur.com/dTjrT.jpg
Also, I found this while tracing out vacuum lines:
https://i.imgur.com/xytTf.jpg
Does that plastic plug look legit? It seems pretty custom to me. Is it something I should be concerned about?
Thanks again!
Edit: Got bored and looked for you lol.
Here's the entire harness if you have old brittle hoses:
http://www.teamgrandwagoneer.com/par...iled/3001.html
As for the MAP sensor hose specifically, I didn't see it. However, I may have missed. Try gettin in contact with them about what you need... I'd bet they have it somewhere lol.
parts@teamcherokee.com
Hope this helps!
#4
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Year: 1989 xj sport 2dr
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Engine: 12 hole bosch Injectors
the vacuum for the map sensor can come from any vacuum port if its the grommet leaking plug the hole in throttle body and tap into a nother constant vacuum source...
#6
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I think I got mine at NAPA for $8.
#7
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Any chance you have that Napa part number still? I can't find it on their website and the online chat guy was no help.
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#8
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Year: 1990
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I just called Napa and they only show the harnesses, a front and rear.
Freegdr is correct. You could use any manifold vacuum source. The issue is gonna be plugging the hole in the throttle body.
Is the harness plugged into the correct hole in the throttle body?
Freegdr is correct. You could use any manifold vacuum source. The issue is gonna be plugging the hole in the throttle body.
Is the harness plugged into the correct hole in the throttle body?
#9
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Yeah, I got the harness from Napa already, that's how I got into this mess. It only plugs in one way. If you look at the picture, that black grommet is a single piece of rubber. As far as I can tell, the top nipple is just there for stabilization. There was nothing plugged into it when I started this affair, and if I put my finger over it, there is no suction, or change in RPM. I think the problem is that the grommet is old and sits in there loosely. I saw a few other threads from Renix engine owners and they said that their's was the same way. Although if any of you have information to the contrary, feel free to let me know. I guess I'll just have to pony up the 30 bucks to get the right part shipped to me. $12 for shipping for a 2 ounce part is just ridiculous! Oh well. Thanks for all the help guys!
#10
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Year: 1991
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Wongfat.......this is gonna sound crazy, and 'lafffa while you a can..a monkee boy!" (ha whats that from? 10 beers you get it right!)
Anyway.....that thin piece o crap plastic tube you took out and replaced with the kit you bought? Hope you kept it?
Here is what I did with the split and broke in half flimsy crap tube....
first i put super glue to the two broke pieces put together as close as possible so they meld close.. waited 20 minutes. then I used black rtv all around that joint, waited about 20 minutes again, then put electrical tape around the wound. as for the split, I put black rtv along the slit, then taped it over with electrical tape...
as for the funky cracked rubber elbow which the chinsy plastic tube goes into, I used the same black RTV all over it and let it dry.
the whole assembly I let dry for 24 hours then put it on the jeep and it has been running great, NO leakee!!!
again, my opinion and what worked for me.
good luck sir!
cpnwrench
#11
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I was actually thinking about using RTV to make the seal. At 30 bucks, I think that may be the way to go. Just put some RTV around the grommet, stick it in there and let it cure. I just need to go lightly enough so that none of it makes it into the throttle body itself. I got nothing on the quote, sorry!
#13
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That thin plastic tubing is used for as reason. That's a critical vacuum signal to the MAP.
Parts houses have the tubing, just not molded. They also have the rubber bends, elbows etc.
Dealer have the molded hoses.
To repair bad spots, simply cut out thr bad spots and slip a small rubber hose over the break.
The thin plastic doesn't collapse like rubber, and being small subtle changes in vacuum cause an immediate reaction in the MAP. Larger rubber lines act like a big storage tank, slowing reaction time = stumbles etc., plus they collapse causing problems too. Jeep engineers really weren't crazy.
Parts houses have the tubing, just not molded. They also have the rubber bends, elbows etc.
Dealer have the molded hoses.
To repair bad spots, simply cut out thr bad spots and slip a small rubber hose over the break.
The thin plastic doesn't collapse like rubber, and being small subtle changes in vacuum cause an immediate reaction in the MAP. Larger rubber lines act like a big storage tank, slowing reaction time = stumbles etc., plus they collapse causing problems too. Jeep engineers really weren't crazy.
#15
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Wongfat.......this is gonna sound crazy, and 'lafffa while you a can..a monkee boy!" (ha whats that from? 10 beers you get it right!)
Anyway.....that thin piece o crap plastic tube you took out and replaced with the kit you bought? Hope you kept it?
Here is what I did with the split and broke in half flimsy crap tube....
first i put super glue to the two broke pieces put together as close as possible so they meld close.. waited 20 minutes. then I used black rtv all around that joint, waited about 20 minutes again, then put electrical tape around the wound. as for the split, I put black rtv along the slit, then taped it over with electrical tape...
as for the funky cracked rubber elbow which the chinsy plastic tube goes into, I used the same black RTV all over it and let it dry.
the whole assembly I let dry for 24 hours then put it on the jeep and it has been running great, NO leakee!!!
again, my opinion and what worked for me.
good luck sir!
cpnwrench
Wongfat's situation is a little different as teh rubber plug going into the throttle body must be deteriorated.