banksie312
NAXJA Forum User
- Location
- Rhode Island
Hey All,
In the middle of a journey that is discovering a problem I've been having with my 99 XJ (Cherokee Classic, 4L). Not sure if I can get tips or maybe this will help someone else down the road.
About 2 months ago my Jeep would occasionally hiccup during an idle, either almost stalling or jumping up to 1800rpm, but only for a moment. It was very random and happened rarely. I then put some serious highway miles during a week long trip (NYC>RI>PA>NYC) and found it having more trouble with the idle. I went on a trip recently (NYC>PHL>NYC) and stalled out a few times when I was getting into town in each direction. I started doing some heavy research and have done a few tests.
1) Sprayed brake cleaner around the intake and exhaust manifolds to see if I had a bad gasket or crack in the header. Wasn't able to get a "rise" out of the engine so it's seeming like it isn't that.
2) Put some fuel system cleaner in the tank hoping that might help. It seems to be helping a bit, but haven't put enough miles in to see. Used some basic STP but ordered BG44K to do another tank's worth...I hear it's the real deal cleaner.
3) Swapped out all the spark plugs. Found out the old owner had platinum plugs in, and when I pulled them they were only a little gummed, but gapped at at least .05-.065ish (I say ish because my gap tool only goes to .045). Gapped all my new, Autolite 985 copper plugs at .035. Started her up and she was hiccuping a lot, almost stalling so I shifted to N and revved for about a minute, then let her sit. Perfect, stable, and quiet idle at 800rpm. First time I've heard that in a while (I know, I know, I should have been more on my game).
So I just did the spark plugs today and did some driving. Car is running great, only one low idle when braking when it went down to 400rpm then jumped back up to 800rpm. The thing about this problem is that it has been inconsistent. One day it's bad, the next day there's no sign of it (though the idle used to be rougher before the spark plug change). Tomorrow I want to check the distributor and cap to see if there are any signs of issue...
I'm hoping that between the fuel system cleaner (in 2 doses) and the new plugs gapped properly, it will fix the issue. Only thing is that I have a 320mi round trip drive coming up later this week. Should I give it some solid driving time to see how she's acting and help the computer learn? Should I do a reset (specifically a fast learning reset: http://naxja.org/forum/showpost.php?p=244834826&postcount=8)? Anyone have any tips or tricks or notice anything I may have missed?
Sorry for the long post, and I appreciate any help that comes my way. Been using this forum to help me out the whole way and it's fantastic.
In the middle of a journey that is discovering a problem I've been having with my 99 XJ (Cherokee Classic, 4L). Not sure if I can get tips or maybe this will help someone else down the road.
About 2 months ago my Jeep would occasionally hiccup during an idle, either almost stalling or jumping up to 1800rpm, but only for a moment. It was very random and happened rarely. I then put some serious highway miles during a week long trip (NYC>RI>PA>NYC) and found it having more trouble with the idle. I went on a trip recently (NYC>PHL>NYC) and stalled out a few times when I was getting into town in each direction. I started doing some heavy research and have done a few tests.
1) Sprayed brake cleaner around the intake and exhaust manifolds to see if I had a bad gasket or crack in the header. Wasn't able to get a "rise" out of the engine so it's seeming like it isn't that.
2) Put some fuel system cleaner in the tank hoping that might help. It seems to be helping a bit, but haven't put enough miles in to see. Used some basic STP but ordered BG44K to do another tank's worth...I hear it's the real deal cleaner.
3) Swapped out all the spark plugs. Found out the old owner had platinum plugs in, and when I pulled them they were only a little gummed, but gapped at at least .05-.065ish (I say ish because my gap tool only goes to .045). Gapped all my new, Autolite 985 copper plugs at .035. Started her up and she was hiccuping a lot, almost stalling so I shifted to N and revved for about a minute, then let her sit. Perfect, stable, and quiet idle at 800rpm. First time I've heard that in a while (I know, I know, I should have been more on my game).
So I just did the spark plugs today and did some driving. Car is running great, only one low idle when braking when it went down to 400rpm then jumped back up to 800rpm. The thing about this problem is that it has been inconsistent. One day it's bad, the next day there's no sign of it (though the idle used to be rougher before the spark plug change). Tomorrow I want to check the distributor and cap to see if there are any signs of issue...
I'm hoping that between the fuel system cleaner (in 2 doses) and the new plugs gapped properly, it will fix the issue. Only thing is that I have a 320mi round trip drive coming up later this week. Should I give it some solid driving time to see how she's acting and help the computer learn? Should I do a reset (specifically a fast learning reset: http://naxja.org/forum/showpost.php?p=244834826&postcount=8)? Anyone have any tips or tricks or notice anything I may have missed?
Sorry for the long post, and I appreciate any help that comes my way. Been using this forum to help me out the whole way and it's fantastic.
