I posted a thread yeaterday about my 94 dying about 5-10 minutes after startup and not restarting. I had put some shiny goodies under the hood aand also replaced the serpentine belt a couple of weeks ago. This morning I used the paper clip method to see what codes were stored (SES light on) and gotH31, H33, H35 H37 in module 1 and H48 in module 4. Before I left diagnostic mode I cleared the codes and have no additional codes after cycling the ignition switch. I then removed the paper clip. There didn't appear to be any active codes. H31 and H35 don't appear on my list of codes and the H37 Makes no sense because the brake lights don't stay on. H33 says MAP sensorcircuit high and H48 says MAF sensor circuit. But since these were H codes and not A active codes where do I go now? The only sensors that have been unplaugged lately were MAF. Coolant temp, and IAT. Those were unplugged when I removed the inlet hose to replace the serpentine belt. I checked the MAF plug and it's tight. Btw, I did use MAF cleaner on it while I had it out replacing the serpentine belt. As far as the Map sesor is concerned, I removed the screws from it and put a polished cover over it with new screws and polished caps for the screw heads but as far as I know it never moved but possibly could have. I don't want to throw a bunch of money at this by randomly replacing stuff so what's my next step? I have a voltmeter if I need to check voltages. BTW, I haven't tried to start it this morning. The battery already seems a little weak after sitting for a couple of weeks and I don't want to run it down till I think the problem may be solved.

 

An update

Later today I tried to start the car after clearing the codes. The battery didn't have enough juice to crank the car. It just caused the solenoid to click. I took out the battery and took it up and had it charged and tested and it was ok. Next, since the battery was that low I suspected maybe the alternator had gone bad so I pulled it and took it up to Autozone and had them test that. It passed also. I'm beginning to suspect the MAP sensor because of the code H33. Recently I had put a polished stainless steel cover on the MAP sensor. The cover came with new screws that have plastic gizmos that hold little chrome plastic caps for the screw head. The holes in the cover didn't quite line up with the holes in the MAP sensor but I could get the screws started. As I tightened them down they drew the cover over and it seemed ok but it kind of worried me that "wedging" it on like that might cause a leak so I pulled it back off and elongated the cover holes just a bit so that there was no wedging effect. I was afraid to overtighten them the first time so I tightened them as tight as I could today. Is it possible that as the engine warmed it created a vacuum leak there and thats what caused it to die and not restart? Anybody have any ideas?

 

This is the way to check the codes using a paperclip followed by a list of the codes.

On a 94-96 you can check the codes with a paper clip as follows:

You short pin "12" to pin "4" and turn the ignition switch to "On" without starting the engine.

The speedometer will display any codes using the same protocol as the 1990-1993 model but there are some changes in the designation for the modules plus additional modules are added:

Module "1" is still the CCM module.

Module "4" is now called the PCM module (Powertrain Control Module) because automatic transmission computer control was added to Engine Control Module in 1994.

Module 7 (on the 1996 model only) is the RTD module. (This is the Real Time Dampening module which replaced the Selective Ride Control module in 1996).

Module 9 is the ABS/ASR module number from 1994 through 1996.
Finally, Module "A", the DERM (Dynamic Energy Control Module --- (the air bag control module) will be requested to show any codes.

Just like the 1990-1993 display, you read the codes on the speedometer (big) and read the module number on the trip odometer (small).

A series of dashed lines for instance “ - - -“ indicates no more stored codes for that module.

A code showing as “C12” for the CCM module (module #1) means no codes are stored. So C12 is a good thing to see.

Again, you can cause the codes to repeat by turning the ignition off for five seconds and then back on.

Turn the ignition off and remove the short to restore normal operation.

To clear the codes,

1. With ignition "off" ground terminal #12 of the DLC (use bent paper clip to connect pin 4 to pin 12)

2. Turn ignition "on".

3. Press trip/odo button on the DIC until 1.7 appears in the trip
monitor area of the instrument cluster.

4. Press eng/met button on the DIC & hold until "---" appears in the
speedometer area of the cluster, this will clear CCM DTC'S.


To clear PCM/ECM codes do the following:


1. Press the trip reset button on the DIC until the desired system is displayed. In this case it will be 4.0.

2. Press trip/odo button on the DIC until the desired diagnostic mode(4.7) is displayed on the trip monitor area of the cluster.

3. Press & hold the eng/met button on the DIC until "---" is
displayed in the speedometer area of the cluster, this will clear PCM codes.


To clear ABS/ASR codes do the following:

Same as above but you’re looking for “9.7” on the trip odo

And here are the codes

1994-1995: Diagnostic Trouble Codes
DTC #11: Malfunction Indicator Lamp Circuit.
DTC #13: Bank #1 Heated Oxygen Sensor #1 Circuit:
DTC #14: Engine Coolant Temperature Sensor Circuit Voltage Low.
DTC #15: Engine Coolant Temperature Sensor Circuit Voltage High.
DTC #16: Distributor Ignition System Low Pulse.
DTC #18: Injector Circuit.
DTC #21: Throttle Position Sensor Circuit Voltage High.
DTC #22: Throttle Position Sensor Circuit Voltage Low.
DTC #23: Intake Temperature Sensor Circuit Voltage High.
DTC #24: Vehicle Speed Sensor Circuit.
DTC #25: Intake Air Temperature Sensor Circuit Voltage Low.
DTC #26: Evaporative Emission Canister Purge Solenoid Valve Circuit.
DTC #27: EGR Vacuum Control Signal Solenoid Valve Circuit.
DTC #28: Transmission Range Pressure Switch Assembly Fault.
DTC #29: Secondary Air Injection Pump Circuit.
DTC #32: Exhaust Gas Recalculation.
DTC #33: Manifold Absolute Pressure Sensor Circuit High.
DTC #34: Manifold Absolute Pressure Sensor Circuit Low.
DTC #36: Distributor Ignition System High Pulse.
DTC #37: Brake Switch Stuck On.
DTC #38: Brake Switch Stuck Off.
DTC #41: Ignition Control Circuit Open.
DTC #42: Ignition Control Circuit Shorted.
DTC #43: Knock Sensor Circuit.
DTC #44: Bank 1 LF Heated Oxygen Sensor #1 Circuit Lean.
DTC #45: Bank 1 LF Heated Oxygen Sensor #1 Circuit Rich.
DTC #47: Knock Sensor Circuit Or Module Missing.
DTC #48: Mass Air Flow Sensor Circuit.
DTC #50: System Voltage Low.
DTC #51: EPROM Programming Error.
DTC #52: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #53: System Voltage Low.
DTC #55: Fuel Lean Monitor.
DTC #58: Transmission Fluid Temperature Sensor Circuit Low.
DTC #59: Transmission Fluid Temperature Sensor Circuit High.
DTC #62: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #63: Bank 2 RF Heated Oxygen Sensor #1 Circuit Open.
DTC #64: Bank 2 RF Heated Oxygen Sensor #1 Circuit Lean.
DTC #65: Bank 2 RF Heated Oxygen Sensor #1 Circuit Rich.
DTC #66: A/C Refrigerant Pressure Sensor Circuit Open.
DTC #67: A/C Pressure Sensor Circuit Sensor or A/C Clutch.
DTC #68: A/C Relay Circuit.
DTC #69: A /C Clutch Circuit.
DTC #70: A/C Clutch Relay Driver Circuit.
DTC #72: Vehicle Speed Sensor Loss.
DTC #73: Pressure Control Solenoid Circuit Current Error.
DTC #74: Traction Control System Circuit Low.
DTC #75: Transmission System Voltage Low
DTC #77: Primary Cooling Fan Relay Control Circuit.
DTC #78: Secondary Cooling Fan Relay Control Circuit.
DTC #79: Transmission Fluid Overtemp.
DTC #80: Transmission Component Slipping.
DTC #81: Transmission 2-3 Shift Solenoid Circuit.
DTC #82: Transmission 1-2 Shift Solenoid Circuit.
DTC #83: Torque Converter Solenoid Voltage High.
DTC #84: 3-2 Control Solenoid Circuit.(Auto Only).
DTC #84: 2nd And 3rd Gear Blockout Relay Control Circuit.
DTC #85: Transmission TCC Stock On.
DTC #90: Transmission TCC Solenoid Circuit.
DTC #91: One To Four Upshift Lamp(Manual Only).
DTC #97: VSS Output Circuit.
DTC #98: Tachometer Output Signal Voltage Wrong.

To run a diagnostic on the PKE system, connect pins 4 and 8 on the ALDL (see pic below to see pin label order)


And the PKE diagnostic system works as follows:
With pins 4 and 8 connected, the PKE light in the Driver Info Centre will flash the codes.

Here is the list of DTCs and what they mean:

DTC #12: Receiver Memory Bad
DTC #13: Transmitter Not in Range
DTC #14: Non-Valid Transmitter Received
DTC #15: Valid Transmitter Received
DTC #16: Passenger Door Button Depressed
DTC #17: Hatch Button Depressed


95s are NOT OBD2.

 

That's great information! I wasn't even aware it was possible to retrive codes on the PKE. I had previously retrieved the codes that were stored. In module 1 I got H31, H33, H35, and H37. in module 4 I got H48. There were no other codes. The only two that seem relevant to me are H33 and H48. H31 and H35 don't appear on any of the DTC code lists i've Found.H37 says the brake light switch is stuck, It's not so this is probably an old code. H33 is MAP sesor circiy high and H48 is MAF sensor circuit.As I explained in the update I added, Their could be a leak at the MAP sensor. I retightened everything and ordered a new seal for the MAP sensor. If there were a problem with the MAF circuit the car would probably run although poorly. My problem is it died about 5-10 minutes after starting it and wouldn't restart.