kurama49

Well, I finally gave up on trying to fix it myself and just dropped it off at a trusted garage. and told them to fix what ever looks wrong with it, It may cost a butt-load, but 1. I need my jeep as soon as possible, and 2. mom doesn't want any more messes in her garage... or the yard. So, Now i just have to play the waiting game, they said they'll have it fixed this week. So far things have been looking ok headgasket wise, no milky oil, no more white exhaust smoke... But they did find that my positive wire was half rubbed through from it rubbing on the shock tower.. [didnt notice this... ] They said it still could be the head gasket, or. it could be the coil, fuel pump, and some other things, but they'll figure it out and have it fixed. So, i guess this is the end of this thread lol, thanks for all the help up until now guys Eispecially cruiser!

67 GMC

Hope it works out for you. I hate paying for a garage to figure out what's wrong since you're paying the mechanic $75/hr to do run through what you've already checked. I hope it's something simple that you missed. I've found that at some garages, you're paying for them to swap out a lot of perfectly good parts as they diagnose the issues.

Make sure you post what the fix is if they find it.

kurama49

Well, the garage determined that my headgasket is ok. but when it came to the high idle and sputtering they gave up and told me to come get it. So, with that being said i still have the problem i started with. but since they couldent figure it out they didnt charge me a cent. So thats good, i guess. So tonight i went over everything again, checked my spark plugs, re-gapped them because they were at .45, and my manual said they were supposed to be at .35 I also filled the tank with high-grade fuel, which seemed to help the sputtering a bit? I also noticed, when the jeep is cold, the sputter isnt there but as soon as it starts warming up, the sputter comes. Tomorrow I'm picking up a intake manifold gasket, a new coil, MAT, and a new cps. these are all things people have told me to try, so I may aswell try them and see if they make a difference.

But for now I still have my little IAC band-aid [plugged off with a peice of rag] on it, which helps keep the idle around 900-1000. And the sputter isnt extremely bad, its just annoying. I'll see if I can make up a video tomorrow to show all of this.

cruiser54

It's not the CPS causing it, and unlikely the coil either.

Is the intake manifold gasket leaking? How have you determined this?

MAT? Did you mean MAP?

How old are your plugs, wires, cap and rotor? If your plugs were at .045, they've probably been in there for as long as they are supposed to be --30,000 miles.

kurama49

Well the plugs, wires,cap and rotor are brand new [as far as i know] And I dont exactly know if it is leaking or not, I'm just kind of guessing that... I cant exactly figure out what else would be causing it. but i did notice, when the jeep is dead cold it runs ok [minus the high idle] but it doesent sputter. as soon as it starts to warm up the sputter comes... its not so bad at first, but the warmer the jeep gets the worse it gets, it feels like the fuel is cut off for a split second and then the jeep come back to life.

freegdr

Does oxygen sensor and coolant temp sensor check out ok ? I noticed after reading that's not been addressed yet ?....http://www.lunghd.com/Tech_Articles/...iagnostics.htm

cruiser54

Rather than discussing what it MIGHT be, how about CHECKING the intake bolts? That's a 3 minute job.

Pull a plug and see if it looks new. 2 minute job.

Test the TPS and it's ground circuit. 10 minute job.

kurama49

Well, i checked all the intake bolts, 1 was a smidge loose, there all tight as I can get them now,

the plugs look fairly new though a bit dirty.



And the tps is set and working ok, 4.97 for my reference voltage and 0.84 as my output voltage, and no resistance to be seen on the ground circut. I also put my old tps on, because my new one wouldent give me a output voltage


I also put on a new set of plug wires because well... they were on sale for $15, plus my old ones looked OEM..




And here is the said peice of rag that keeps my idle down.


I also went and put a very thin bead of silicone around the gasket of the throttle body to make sure that it sealed right...

And still none of this helped my problem.

I will have to try this tomorrow when its no so cold.

And the MAT sensor I was told to replace by a family friend [who's been a mechanic for 30 years] is located here on the intake manifold


[picture stolen from the interwebs]

cruiser54

CTS and O2 sensor usually cause a low and rumbly idle.

Can you give us a photo of the valve cover and vacuum harnesses? What happens to the idle if you disconnect the rear hose from the valve cover and put your finger over it?

kurama49

ok, just went out and got these pics, and did what you said with the rear hose and well... nothing happens at all. no suck from it or anything.



This is that rear hose gromet


It looks like something's supposed to be here? but nothings been there since i purchased the jeep


And the hoses around the air box

codenameanimal

Have you tried checking to make sure all of the fuel injectors have their o-rings this causes my mothers jeep high idle problem. Also, if you want to see if your manifold gasket is leaking use soapy water it will create bubbles where the air pockets are.

kurama49

I tryed spraying carb cleaner around there, didnt change anything, I'll get some O-rings tomorrow, because i dont think the injectors are supposed to spin around somewhat freely?

67 GMC

Cruiser just posted the pictures for the vacuum and vapour lines. That plastic bulkhead fitting at the front of the engine is where the vapour line from the valve cover would normally go. On your Jeep, there's a rubber hose instead of a hard plastic tube. It probably works just as well.

Here's a link to the diagrams. Very helpful.

https://www.cherokeeforum.com/f2/ren...iagram-179439/

kurama49

Ah that helps a bit. I also just gained another problem, I lost spark at the coil... just.. randomly. nothing at all. I'm getting fuel cause I can smell it, but to do a 1-man test of the coil I put a longer plug wire on it, and put a sparkplug in the end and placed it on the valve cover, then got inside and peeked at it through the gap between the hood and header panel, cranked and no spark from it at all...

cruiser54

Yes. They spin.