I have a '98 neon 2.0 DOHC that randomly quits. New coil, plugs, wires, etc. Dash board seems to have tourettes (speedo jumps and sputters, tach occasionally freezes around 2200, oil light comes on intermittantly along with every other gauge in the cluster) Fuel pump runs and I have good pressure at the fuel rail. This is completely random as it will happen 2 or 3 times in none day, then not at all for weeks???
TSB for the tach problem:
NO: 08-04-98
GROUP: Electrical
DATE: Jan. 30, 1998
SUBJECT:
Tachometer Fluctuates And/Or Bounces MODELS:
1997-1998 (PL) Neon THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A TACHOMETER, BUILT PRIOR TO DECEMBER 12, 1997 (MDH 1212XX).
SYMPTOM/CONDITION:
Tachometer fluctuates and/or bounces as much as 300 to 1000 RPM while driving at a steady speed/RPM. DIAGNOSIS:
Using the Mopar Diagnostic System (MDS) or the Diagnostic Scan Tool (DRB Ill) with the appropriate Diagnostic Procedures Manual, verify all engine/transmission systems are functioning as designed. If Diagnostic Trouble Codes (DTC's) are present, record them on the repair order and repair as necessary before proceeding further with this bulletin. Using an ohmmeter, check the resistance between the PCM case and the battery ground. If the resistance is less than 1 ohm, refer to the appropriate Powertrain Diagnostic Manual for further tachometer diagnostics. If the resistance is more than 1 ohm, perform the Repair Procedure. POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:Labor Operation No: 08-19-01-98 0.3 Hrs.
FAILURE CODE: XX - Service Adjustment
ALLDATA repair procedure:
This bulletin involves tightening the four screws holding the case of the Powertrain Control Module (PCM) to ensure complete grounding. If the ground is incomplete, the signal to the tachometer is momentarily interrupted.
1. Disconnect the negative and positive cables from the battery. 2. Remove the washer bottle neck. 3. Squeeze the tabs on the Power Distribution Center (PDC) while pulling up to remove the PDC from the mounting bracket. Lay the PDC aside to gain access to the PCM bracket screws. 4. Remove the three screws attaching the PCM to the body. 5. Lift the PCM up and disconnect the two 40-way connectors. 6. Remove the PCM. 7. Turn the PCM over to the back side. Torque the four screws (at each corner) to 6.8 Nm (60 in. lbs.) using a manual torque wrench. 8. Attach the two 40-way connectors to the PCM. 9. Install the PCM. Torque the mounting screws to 9 Nm (80 in. lbs.). 10. Install the PDC by pushing it down into the brackets. 11. Install the washer bottle neck. 12. Connect the positive and negative battery cables. 13. Using an ohmmeter, check the resistance between the PCM case and the battery ground. If the resistance is less than 1 ohm, the repair is complete. 14. If the resistance is above 1 ohm, remove the PCM and perform the following steps: A. Remove one PCM corner screw at a time, then insert back into the hole, and torque to 6.8 Nm (60 in. lbs.). This will work the screw through the paint creating a better ground. B. Repeat for remaining three screws.
---------- Post added at 10:09 PM ---------- Previous post was at 10:08 PM ----------
It is possible that this problem is causing both problems.
Check back with any codes you may have.
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