|09-11-2013 06:12 AM|
|WallyGator215||When my 87 4.2 was all put back together I still had a big idle problem and bad hesitation on acceleration. Went through vacuum system and the vacuum advance wasn't working properly. Changed a few lines and tool care of the problem. Let me know what you guys come up with|
|09-10-2013 10:00 AM|
|RVer||My 90 YJ had the same problem. Did Nutter Bypass, replaced coil, plugs, plug wires, distributor cap, rotor,fuel filter....and still had the problem...Replaced the Carb with a "no computer feedback" carb ($165.00), problem FIXED..|
|09-09-2013 06:12 AM|
Vacuum lines are a high possibility.
Another thing to check is the position sensor under the Rotor. There is a 6 bladed sleeve rotor shaft, and a magnetic pick-up in the Distributor housing. Sometimes shavings start sticking to the magnet which will try to bridge the gap between the sleeve and the sensor. When that happens it will make the timing irregular. You can just wipe it off.
|09-08-2013 10:26 AM|
|willylou81||I had similar symptoms, replaced many of the same things you did and finAlly a new coil fixed it, to my amazement. For 30 bucks it could be the cheap solution I would try that. I have a thread I started before that shoes the symptoms mine had|
|09-08-2013 08:41 AM|
|09-08-2013 08:16 AM|
|tamron||I had a lot of these problems a couple of years ago, I have an 89 and everything seemed to checkout ok. I ended up spending 80 bucks and changed the computer located under the wind shield washer reservoir. Ran perfectly after that and only took me a few minutes to swap. My dash lights never did come back on though... reminds me I really need to look into that.|
|09-06-2013 08:21 PM|
|09-06-2013 08:10 PM|
|harleydragon||sure has all the symptoms of a vacuum leak somewhere|
|09-06-2013 08:03 PM|
|WallyGator215||I have 87 4.2 auto yj. Maybe different motor than yours but I had the same engine issues. Up and down idle, hesitation on acceleration. Stalling out at stops and sometimes on acceleration but ran great when it got goin. I sprayed carb cleaner on the intake/exhaust manifold gaskets to the block and it idled perfect. Replaced them and re torqued the bolts. Then did carb gaskets to intake. Ran better but hesitation was still there. Went through vacuum system and found broken T. Fixed that for $2. She's running perfect now. Spray that carb cleaner around the gaskets and see if it changes. Then you replace whatever gaskets are leaking and torque to spec. Very important to get that right|
|05-07-2013 01:23 AM|
|05-06-2013 04:33 PM|
|dstryker||@ILuvJeepyj, I have a 90 model with the same symptoms. I thought it was a stuck valve so I tore the engine down had the head rebuilt put new rings and bearings in put it all back together started it up, and no different. Although mine backfires just a bit when trying to accelerate. Not all the time but sometimes. Mine acts like the spark is not advancing. I have replaced all of the other obvious things like mentioned above, but I still haven't found the problem. I will ck grounds and fuel pressure to eliminate those areas. Anything else from anyone would greatly be appreciated.|
|05-06-2013 03:26 PM|
|khende||I am going with the bad ground, My YJ had the same issues when I bought it. Even though the stock ground appeared to be wire correctly there was still a problem. I bought on of those old mesh ground cables, cleaned the firewall of all paint and hooked up the ground. The second I did that the moter smoothed out and ran much better.|
|05-06-2013 12:19 PM|
|Billmummey||I ALWAYS start with a fuel filter in situations like this just because its a 5 dollar part and 10 min to change... It's the easiest to eliminate out of the equation|
|05-06-2013 12:16 PM|
|Billmummey||I think he said he was burning up the clutch trying to keep it going at low speeds, I think it was this tread anyway|
|05-06-2013 10:02 AM|
Can you tell us what the volts you are getting from the battery all the way through?
What fuse exactly did you blow. Also you say you did the nutter bypass exactly how did you do it there are a couple of writes up on that and my understanding is some work better than others. Lastly when you get it started can you keep it running smoothly with carb cleaner or starter fluid? If yes then it could be the fuel filter or bad gas but honestly for me that very seldom is the problem unless the filter is almost completely plugged. Is your jeep using a mechanical fuel pump or electric?
My reasoning behind all this is a bad fuel filter will not make your dash lights go out, unless there are some other things going on like you popping the clutch in and out as it stalls trying to keep it going.
Sorry for the long post but details can be very important.
|05-06-2013 09:41 AM|
|barjeep||i agree with billmummey, or just bad gas|
|05-06-2013 01:27 AM|
I had a similar problem with mine idling rough and rpms jumping all around. I ended up changing the IAC and now it idles perfectly with no vibration or rpms jumping up and down.
As far as not having the get up and power, I would like to know that as well. Mine is doing the same and can't seem to figure it out.
|05-06-2013 12:37 AM|
|Billmummey||Sounds like a fuel filter to me|
|05-05-2013 11:55 PM|
|iLuvJeepYJ||Also, I have done the butter bypass|
|05-05-2013 11:54 PM|
|05-05-2013 10:05 PM|
By the end of reading your issues, I was thinking short also or possibly a bad ground. Try cleaning the grounds on the block ( located by the distributor cap) could be a bad vacuum.
Have you checked what engine codes you're getting?
|05-05-2013 07:10 PM|
|Cole Noah||Try a nutter bypass. That might work. You should probably check all you wires as well. Sounds like there's a short in there somewhere. Best of luck!|
|05-05-2013 05:45 PM|
|05-05-2013 05:37 PM|
Jeep running horribly..PLEASE HELP!
Alright guys, my jeep has been running rough for over half a year and I just can't figure out what the hell is going on
Here are my problems:
-horrible idle(by that i mean it shakes the vehicle, changes between 1100-500 rpm randomly, sometimes it just cuts off)
-major hesitation upon acceleration(has pretty much no power and im wearing out my clutch trying to acclerate without stalling)
-gets smoother at higher rpm(Above 2000) but still not much power
-i cant really drive in 4th gear without her bogging down on me so really im having to stay in 3rd and ever since its been running like this i have been no faster than 55mph
-when i come to a stop sign/red light/ or sharp turn where i have to press in the clutch, it wants to cut off. i literally have to heel/toe it when i come to a stop
-it started doing this last summer
-doesnt matter if the engine is hot or cold it still idles like ****
-i have done the basic tune up including plugs, plug wires, pcv, cap, rotor, got rid of the egr when i installed the motocraft carb- did those about 4 months ago
-sounds like a tractor at idle and revs up slowly
- i have checked the timing, 8 tdc
-did the MC2100(non-smog) upgrade a couple of months ago thinking that would solve the problem but obviously did not. it did help out a little though because now i can idle below 1000rpm....barley but yeah
-im wondering if i did the TFI upgrade would fix it?
-radio keeps going out, along with my dash lights
-i do have a meter
- it has been running like this even when i had the old carter carb on there
-it was sitting for about 4 years not being used and i got it running last summer and ran great until this problem started one morning when i turned it on wanting to go for a nice ride