Garon Keaton

Greets guy and gals,
I have a 92 xj 4.0 4x4 Laredo. Last night it started fine, ran like a champ, went to shut down, then it would not restart. She turns over, but I have no spark. Cps read 36 ohms or so , so I replaced it. Still no start. Replaced the coil as I had a new one on hand, still nothing. Went out on a limb and replaced the distributer (cheaper than the pick up), still won't start, but wants to catch a little. Obd 1 codes are 12, 17, 21, 33, 35, 54, 76, and finally 55. Seemed like I had adequate fuel pressure at the rail. The only thing I can think of is my oil pressure gauge was starting to twitch a little bit. Also sprayed starting fluid when I was walking through the diag steps. I did find that my ignition fuse was blown. Replaced with no change, unfortunately. So, I am really stuck. I'm thinking a possible com at this point. Help? Please? (With sprinkles, even!)

EEVEE

11

No crank reference signal detected during engine cranking. Intermittent loss of either camshaft or crankshaft position sensor.

12

Positive battery input to PCM was disconnected within the last 50 Key-on cycles.

13

No difference recognized between the engine MAP reading and the barometric (atmosphere) pressure reading from start-up.

14

MAP sensor input above or below acceptable voltage. 5 volt output to MAP sensor open.

15

No vehicle speed sensor signal detected during driving load conditions.

17

Engine did not reach operating temperature within acceptable limits

21

Upstream oxygen sensor response slower than minimum required switching frequency.

Upstream oxygen sensor heating element circuit malfunction.

Downstream oxygen sensor heating element circuit malfunction.

Downstream oxygen sensor input voltage maintained above the normal operating range.

Oxygen sensor voltage too low, tested after cold start. (Upstream or Downstream)

Left oxygen sensor input voltage maintained above the normal operating temperature.

22

Engine coolant temperature sensor above or below acceptable voltage.

23

Intake air temperature sensor input above or below acceptable voltage.

24

Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor.

25

A shorted or open condition detected in one or more of the idle air control motor circuits. Actual idle speed does not equal target idle speed.

27

Injector #1 thru 6, or any combination of individual injectors driver does not respond properly to the control signal.

31

An open or shorted condition detected in the A/C clutch relay circuit. Insufficient or excessive vapor flow detected during fuel evaporation emission system operation.

33

An open or shorted condition detected in the duty cycle purge solenoid circuit. (A/C clutch relay circuit)

34

An open or shorted condition detected in the Speed Control vacuum or vent solenoid circuits. Speed control switch input below the minimum acceptable voltage.

37

Relationship between engine speed and vehicle speed indicates no torque converter clutch engagement. An open or shorted condition detected in the torque converter part throttle unlock solenoid control circuit. Incorrect input state detected for the Park/Neutral switch. Auto only.

41

An open or shorted condition in the generator field control circuit.

42

An open or shorted condition detected in the auto shutdown relay circuit. An open condition detected in the ASD relay output circuit. An open or shorted condition detected in the fuel pump relay control circuit. An open circuit between PCM and fuel gauge sending unit. Circuit shorted to voltage between PCM and fuel gauge sending unit. No movement of fuel level sender detected.

43

Peak primary circuit current not achieved with maximum dwell time. Misfire detected in one or more cylinders 1 thru 6. (4 and 6 cyls.)

44

Battery temperature sensor in voltage above or below acceptable range.

46

Battery voltage sense input above target charging voltage during engine operation.

47

Battery voltage sense input below target charging during engine operation. Also, no significant change detected in battery voltage during active test of generator output circuit.

51

A lean air/fuel mixture has been indicated by an abnormally rich correction factor.

52

A rich air/fuel mixture has been indicated by an abnormally rich correction factor.

53

PCM Internal fault condition detected.

54

No camshaft signal detected during engine cranking.

55

Completion of fault code display on Check Engine lamp.

62

PCM Failure to update service reminder indicator

63

Unsuccessful attempt to write to an EEPROM location by the PCM.

64

Catalyst efficiency below required level. (Same as code 72)

65

Power steering high pressure seen at high speed. (2.5L only)

72

Catalyst efficiency below required level. (Same as code 64)

77

Malfunction detected with poser feed to speed control servo solenoids

EEVEE

11 No ignition reference signal detected during cranking OR timing belt skipped one or more teeth; OR loss of either camshaft or crankshaft position sensor.
12 Battery or computer recently disconnected
13 MAP sensor or vacuum line may not be working
14 MAP sensor voltage below .16V or over 4.96V
15 No speed/distance sensor signal
16 Loss of battery voltage detected with engine running
17 Engine stays cool too long (bad thermostat or coolant sensor?)
OR
17 (1985 turbo only): knock sensor circuit
21 Oxygen sensor signal doesn't change (stays at 4.3-4.5V). Probably bad oxygen sensor
22 Coolant sensor signal out of range - May have been disconnected to set timing
23 Incoming air temperature sensor may be bad
24 Throttle position sensor over 4.96V
25 Automatic Idle Speed (AIS) motor driver circuit shorted or target idle not reached
26 Peak injector circuit voltage has not been reached (need to check computer signals, voltage reg, injectors)
27 Injector circuit isn't switching when it's told to (TBI)
OR (MPI) injector circuit #1 not switching right
OR (turbo) injector circuit #2 not switching right
OR (all 1990-) injector output driver not responding
- check computer, connections
31 Bad evaporator purge solenoid circuit or driver
32 (1984 only) power loss/limited lamp or circuit
OR
32 EGR gases not working (1988) - check vacuum, valve
OR
32 (1990-92) computer didn't see change in air/'fuel ratio when EGR activated - check valve, vacuum lines, and EGR electrical
33 Air conditioning clutch relay circuit open or shorted (may be in the wide-open-throttle cutoff circuit or normal on early 80's models if you don't have air conditioning)
34 (1984-86) EGR solenoid circuit shorted or open
OR
34 (1987-1991) speed control shorted or open
35 Cooling fan relay circuit open or shorted
OR
35 idle switch motor fault - check connections
36 (turbo only) Wastegate control circuit open or shorted
37 Shift indicator light failure, 5-speed
OR
part throttle lock/unlock solenoid driver circuit (87-89)
OR
solenoid coil circuit (85-87 Turbo only)
OR
Trans temperature sensor voltage low (1995 and on)
41 Alternator field control circuit open or shorted
42 Automatic shutdown relay circuit open or shorted
OR
42 Fuel pump relay control circuit
OR
42 Fuel level unit - no change over miles
OR
42 Z1 voltage missing when autoshutdown circuit energized (The Z1 voltage is the voltage of the circuits fed by the autoshutdown relay. This typically includes fuel pump and switched-battery feed to the ignition coil)
43 Peak primary coil current not achieved with max dwell time
OR
43 Cylinder misfire
OR
43 Problem in power module to logic module interface
44 No FJ2 voltage present at logic board
OR
44 Logic module self-diagnostics indicate problem
OR
44 Battery temperature out of range
45 Turbo boost limit exceeded (engine was shut down by logic module)
46 Battery voltage too high during charging or charging system voltage too low
47 Battery voltage too low and alternator output too low
51 Oxygen sensor stuck at lean position (this may be tripped by a bad MAP sensor system causing a rich condition. If you get hot rough idle and stalling, especially on deceleration, accompanied by flooded engine and difficulty restarting, that can be a bad MAP sensor causing the O2 sensor to try to compensate. If you get poor cold driveability, stumbling and bucking, and acceptable warm driving with poor gas mileage (a drop of 10 mpg or more), that is usually the O2 sensor.
OR
51 Internal logic module fault ('84 turbo only).
52 Oxygen sensor stuck at rich position
OR
52 Internal logic module fault ('84 turbo only)
53 Logic module internal problem
54 No sync pickup signal during engine rotation (turbo only)
OR
54 Internal logic module fault ('84 turbo only) - or camshaft sensor/distributor timing
55 End of codes
61 "Baro" sensor open or shorted
62 EMR mileage cannot be stored in EEPROM
62 PCM failure SRI mile not stored
63 Controller cannot write to EEPROM
64 Catalytic converter efficiency failure
65 Power steering switch failure
66 No CCD Message From TCM and/or No CCD Message From BCM

Garon Keaton

​​​​​​I was able to test fuel pressure at the rail, came up with 31 psi, seems low to me, also getting spark now at all cylinders. I don't have a noid light set to check the injectors. Once again, I would appreciate any advice!

tjwalker

31 is the exact mfg. spec for fuel pressure for your vintage so your fuel pressure is good.

What color is your spark? You are looking for a strong, blue, snapping spark.

What brand crank sensor did you install?

PatHenry

When you installed the distributer did you exactly align it to the mark or offset it?
I don't have first-hand experience but I read a few posts where the distributer had to be slightly offset a bit. I'll see if I can find the post.

PatHenry

https://www.cherokeeforum.com/f2/dis...-4-0-a-240660/

​​​​​​​There it is - it has photos.

4.3L XJ

Two issues. Code 34, no camshaft signal detected. Better check all that again. You had the distributor out. It has to be installed with engine at top dead center with the rotor at the 4 O'clock position. Otherwise it will not be smart enough to know what to do

Garon Keaton

Today I pulled the alternator out, and warrantied it, I was getting inconsistent readings from it when I put it on my tester. It was less than 3 months old. I'm wondering if it popped the fuse, cps and possibly damaged the pcm..... I also put in a new fuel pressure regulator, as it looked O.E. I also have a new set of plugs and wires to install. as for spark color, it was a red/yellow. that was through an in-line tester. I don't have a calibrated one. I also have another new coil (this one a MSD) that I didn't have handy when I put the other newish coil in. Also, the new plugs are the E3 Diamondfire ones (i got a really good deal on them) Tomorrow, I will go to one of the local salvage yards, as they have a 93 xj Laredo, newly arrived, and pull the pcm, I suppose. All the Sensors and such that I installed so far have been BWD, except for the distributor, which was a duralast gold (only one available quickly) It seems like I am putting a lot of money into the jeep here lately, and honestly, she's worth it, I put a lot of miles on her, and other than the alternator, a set of plugs and a tps, I haven't had a single issue for the past 3 years, and approximately 70k miles. She's my daily driver, and my home away from home. Thanks for the help, folks! when i got to change the plugs out tomorrow, I'll put it to TDC and reset the distributor.

Garon Keaton

Greets, guys and Gals!
I put in a used pcm today, aaand.... she started! She is running poorly, but running. she seems to buck and sputter under load, and she isn't shifting right. However, I just drove her 62 miles home. OBD code 51 has shown up. Definitely running rich. She is acting like she has a bad TPS, and there is a a pinging noise, kinda like a couple of loose washers banging around on a loose bolt. I have trouble with noises, as I am hearing impaired (Tanks!!) I cant tell if it is like a timing chain rattle, or spark ping. The doner XJ was a 94. and the PCM seems a little lighter than the old one, I do not know if that makes any difference or not.
Thanks!

PatHenry

The key thing with the PCM is that you use EXACTLY the same part number. So long as they are, you should be good. If not, it's possible that could cause abnornal operation.

Caish

Start checking grounds, start at the one by the dipstick tube.

ElMartillo

Here is an indicator of your problem: you put on a new fuel pressure regulator even though you had good fuel pressure, because the pressure “seemed” low to you and the regulator looked old.

Just throwing parts at your XJ based on how you feel about them is not good diagnostic practice.

Slow down and focus. PAY ATTENTION to the advice you begged for with “please” and “sprinkles on top”.

Start with the basics, fuel, spark, air.

Work on one thing at a time, rule it out.

I don’t beleive an alternator can “pop” electronics as it’s attached to the battery which acts as a “surge protector”.

Get the alternator in place, make sure your distributor is installed correctly, put the original pcm in and start over. Refresh all your grounds.

1 Test.
2 If you don’t know, ask.
3 Pay attention to advice.
4 Do as advised.
5 See #1

I hope you get your XJ running well again, soon.

Garon Keaton

Greets folks!
Just a quick update. On my Jeep so far I have replaced the crank sensor, the distributor, plugs, wires, coil, and fuel pressure regulator. I also cleaned and refreshed all the grounds, located from the chart on alldata. I also put the engine to top dead center, and reinstalled the distributor according to the installation instructions. I obtained a pcm from a 94 country xj that would allow my xj to start and run, albeit very poorly, and 2 additional pcm's that the part numbers are correct, which DO NOT allow her to start. When turning over with the correct part number pcm's about every other revolution or so, it seems to want to catch. To me, this just seems weird, and it has me and several others stumped.

PatHenry

Did you try the distributor offset per the link I provided earlier?