Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
Yep gaps at .35
-
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96 XJ Running Rough..thowing mulitple codes
- Thread starter Bobby@Bullydog
- Start date
winterbeater
NAXJA Forum User
- Location
- Royal Oak, Michigan
Why do you think compression doesn't matter? Fuel, air, compression, spark at the right time. Burned valves, head gasket leak, bad rings, cracked head, could all cause low compression.
- Location
- Roanoke VA
I've had problems with the ignition coils on both of my 96 XJ's cracking and causing issues, eventually shutting down. Look the coil over good.
I fixed both of mine with the "Screamin Deamon" coil from the Firepower kit.
I fixed both of mine with the "Screamin Deamon" coil from the Firepower kit.
lawsoncl
NAXJA Forum User
- Location
- North Idaho
Try taking the hold down bolt out of the distributer and give it a slight turn either direction. If that fixes the idle, then you know its a cap/rotor/dist issue.
WB9YZU
NAXJA Forum User
- Location
- Madison, WI
Does it run badly when "cold" or just when "Warm"?
A bad O2 heater fuse will not cause a no-start condition, atleast on a OBD II system, because the PCM is ignoring those sensors until warm. However, when the systems starts to go closed loop, the PCM will look for the O2 sensors. If they are not up to temperature, the mixture will change radically.
BTW: What is the year of this XJ? I didn't see that in the posts.
-Ron
A bad O2 heater fuse will not cause a no-start condition, atleast on a OBD II system, because the PCM is ignoring those sensors until warm. However, when the systems starts to go closed loop, the PCM will look for the O2 sensors. If they are not up to temperature, the mixture will change radically.
BTW: What is the year of this XJ? I didn't see that in the posts.
-Ron
Last edited:
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
its a 96
And it runs rough cold or warm doesnt matter.
I checked codes while i was driving yesterday and got 7 codes!!
p0300
p0301
p0302
p0303
p0304
p0141
p0138
ive replaced the upstream o2 sensor previously so i wouldnt assume is trashed again. the down stream from what ive read doesnt affect fuel mixture and honestly dont think it would cause a mis fire. Ive narrowed it down to the PCM or a wiring harness issue now...its all I can think of
And it runs rough cold or warm doesnt matter.
I checked codes while i was driving yesterday and got 7 codes!!
p0300
p0301
p0302
p0303
p0304
p0141
p0138
ive replaced the upstream o2 sensor previously so i wouldnt assume is trashed again. the down stream from what ive read doesnt affect fuel mixture and honestly dont think it would cause a mis fire. Ive narrowed it down to the PCM or a wiring harness issue now...its all I can think of
i would say the magnetic pickup/stator/cam position sensor in the distributor and the cps need to be tested if 2 cylinders arnt firing.
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
I replaced the Pick up coil and it didnt change a thing.
Im getting a Noid Light today to test the injectors to see if its a harness issue.
MTBracer367
NAXJA Forum User
- Location
- northeast pa.
well seeing as most of your codes are o2 sensor related i would look there
seeing as you don't have a cat(i personally don't care, some others o here might get uptight about it though) that would explain the codes for you downstreme 02 which has a lot to do with regulateing your emissons which could cause your engine to run poorly and especially suck down gas. i would imagaine if you put a cat back in it would help your gas millage and probably smooth out your idle
i had a smewhat similar problem with my 98 xj and my gf's 97 xj and in both cases it was the up streme o2 sensor. now i know you said you already replaced that but i don't think it would hurt to try it again it's not uncommon to get a bad part even if it's brand new, and seeing as it's new it should still be under warrenty so it shouldn't cost you a penny to swap it out
just my $0.2
-Dylan
seeing as you don't have a cat(i personally don't care, some others o here might get uptight about it though) that would explain the codes for you downstreme 02 which has a lot to do with regulateing your emissons which could cause your engine to run poorly and especially suck down gas. i would imagaine if you put a cat back in it would help your gas millage and probably smooth out your idle
i had a smewhat similar problem with my 98 xj and my gf's 97 xj and in both cases it was the up streme o2 sensor. now i know you said you already replaced that but i don't think it would hurt to try it again it's not uncommon to get a bad part even if it's brand new, and seeing as it's new it should still be under warrenty so it shouldn't cost you a penny to swap it out
just my $0.2
-Dylan
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
Yea from what I have read up on the downstream o0 sensor, it does not affect the fuel mixture just checks to make sure the upstream is working. Now when I replaced it the first time it ran GREAT for about a week then BAM...problems Now that was with old plugs, cap, wires, rotor and all of that good stuff..and when i changed plugs they were pretty nasty so that could be an issue again and ive thought about it but i still think theres something deeeper. Ill swap out with a new o2 sensor this week and see what it does then.
MTBracer367
NAXJA Forum User
- Location
- northeast pa.
when i had my problem i was the same way, i was convinced i had a burnt valve until i rebuilt my top and and still had the same problem
i've come to notice with these things more often then not it's what your convinced it isn't lol
i've come to notice with these things more often then not it's what your convinced it isn't lol
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
It drives you crazy doesn't it!!!
Im not one to just throw parts at it til it fixes it. I like to ask around and save some time and frustration.
Im not one to just throw parts at it til it fixes it. I like to ask around and save some time and frustration.
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
Well i just tested the injector harness with a Noid Light and they are all firing like they should be. So its on to the ECM now i think
jneary
NAXJA Forum User
- Location
- springfield, virginia
with the money your wasting throwing parts at it, you could take it to a shop that can properly diagnose it for you
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
Taking it to a shop...ha..no way i would ever do that, that would hurt my pride.
At least this way i learn the insides and outs of the motor and take pride in fixing it once i figure it out.
At least this way i learn the insides and outs of the motor and take pride in fixing it once i figure it out.
hope you mean .035 not .35
plugs were nasty? what color and condition were they in? you can tell alot from the condition of the plugs.
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
I meant .035 but you got the idea.
and the first set of plugs were just black as coal. and number 5 and 6 threads had some oil on them. After the tune up the plugs are all a caramel color like they are supposed to be. My Misfire is only present at idle. On the highway it has plenty of power and doesnt sputter or misfire at all. This is why I am so confused here because it runs good off of idle but it just idles like a tractor.
and the first set of plugs were just black as coal. and number 5 and 6 threads had some oil on them. After the tune up the plugs are all a caramel color like they are supposed to be. My Misfire is only present at idle. On the highway it has plenty of power and doesnt sputter or misfire at all. This is why I am so confused here because it runs good off of idle but it just idles like a tractor.
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
Well I finally swapped ECMs with my neighbor and that didnt fix a thing
First code that comes up now is p0138 saying theres a circuit failure on the upstream o2 Sensor..so im gonna take it back to autozone and get a new one tomorrow.
First code that comes up now is p0138 saying theres a circuit failure on the upstream o2 Sensor..so im gonna take it back to autozone and get a new one tomorrow.
did you check the fuse for the o2 heater curcuit?
Bobby@Bullydog
NAXJA Forum User
- Location
- Texas
Yea it was good but i went ahead and put another one in it. Didnt change a thing.