1989 DeVille Cold Start Problem Update

[Dennis DiNorcia]

I could not locate my original post so I am posting it again. To follow up to my original, I have a problem with cold acceleration. I usually start the car, run it a minute or so then take off with no problem. For the past several months of winter and summer take off the car chokes and bucks for several miles before sometimes it will clear up and run smooth. It will only do it on acceleration. As the car gets yp to speed it runs fine as long as I do not hit the pedal then it happens again. It's still in the shop again. Car was tuned up appx 20,000 miles ago with plugs, wires, fuel filter etc. The shop has cleaned the throttle valve body as someone suggested, cleaned the fuel injectors, changed some vacuum lines. They have ran a scan and when it shows a code they clear it and run it again and it shows different codes. I asked if it could be an exhaust restriction and he feels there is too much power to indicate that. He thinks it is ignition related, possibly a wire arcing or ?? Anyone have any suggestions that he might not be looking for? Thanks for the help.

[J]

 what codes are cleared? 

To Retrieve Codes from 80's Cadillac:

1. Turn the ignition "ON". Engine can be either OFF or RUNNING.
2. Depress the "OFF" and "WARMER" buttons on the ECC panel simultaneously and hold until "--" appears. "88" will then be displayed which indicated the beginning of the diagnostic readout.
3. Trouble codes will be displayed on the digital ECC panel beginning with the lowest numbered code. Note that the MPG panel goes blank when the system is displaying as the diagnostic mode.

*Clear codes by pressing OFF and HI simultaneously until "00" appears on the display
** Exit diagnostic by pressing "ECON" or "AUTO" or turning the ignition off for 10 seconds


1980's Diagnostic Codes
The following codes are programmed
into the ECM


  Code   Circuit Affected 
00 (E00)   No PCM systems faults 
12 (E12)   No TACH Signal 
13 (E13)   O2 Sensor Not Ready 
14 (E14)   Shorted Coolant Sensor 
15 (E15)   Open Coolant Sensor 
16 (E16)   Generator Voltage Out Of Range 
17 (E17)   Crank Signal Circuit High 
18 (E18)   Open Crank Signal Circuit 
19 (E19)   Fuel Pump Circuit High 
20 (E20)   Open Fuel Pump Circuit 
21 (E21)   Shorted Throttle Position Sensor Circuit (DFI)
  Wide Open Throttle (WOT) Position Sensor Circuit (all others)
22 (E22)   Open Throttle Position Sensor Circuit 
23 (E23)   EST/Bypass Circuit Shorted or Open (DFI)
  Mixture Control (M/C) Solenoid Open (Carbureted)
  MAT Sensor Circuit - Low Temp (TBI/all others)
24 (E24)   Vehicle Speed Sensor (VSS) Failure 
25 (E25)   Modulated Displacement Failure (v8-6-4)
  EST/Bypass Circuit Shorted or Open (HT4100)
  MAT Sensor Circuit - High Temp (TBI/all others)
26 (E26)   Shorted Throttle Switch Circuit 
27 (E27)   Open Throttle Switch Circuit 
28 (E28)   Open Fourth Gear Circuit 
29 (E29)   Shorted Fourth Gear Circuit 
30 (E30)   Idle Speed Control Circuit 
31 (E31)   Shorted MAP Sensor Circuit (DFI)
  Canister Purge Problem (all others) 
32 (E32)   Open MAP Sensor Circuit (DFI/TBI)
  BARO Sensor Circuit Problem (Carbureted) 
33 (E33)   MAP/BARO Sensor Correlation (DFI)
  Shorted MAP Sensor Circuit (all others)
34 (E34)   Vacuum Sensor/MAP Hose (DFI)
  Open MAP Sensor Circuit (all others)
35 (E35)   Shorted BARO Sensor Circuit (DFI)
  Idle Speed Control Circuit Shorted (all others)
36 (E36)   Open BARO Sensor Circuit 
37 (E37)   Shorted MAT Sensor Circuit 
38 (E38)   Open MAT Sensor Circuit 
39 (E39)   TCC Engagement Problem 
41 (E41)   Electronic Spark Timing (EST) Problem 
42 (E42)   Electronic Spark Timing (EST) Circuit Open 
43 (E43)   Electronic Spark Control (ESC) Problem 
44 (E44)   O2 Sensor Lean 
45 (E45)   O2 Sensor Rich 
51 (E51)   PROM Insertion Fault 
52 (E52)   ECM Memory Reset Indicator 
53 (E53)   Distributor Signal Interrupt (HT4100)
  ECM Unit Fault (V6 Models)
  EGR Valve Vacuum Problem (all others) 
54 (E54)   Mixture Control (M/C) Solenoid Shorted 
55 (E55)   ECM/Oxygen Sensor Fault
60 (E60)   Drive (ADL) Switch Circuit 
61 (E61)   Set and Resume Switch Circuit 
62 (E62)   Car Speed Exceeds Maximum Limit 
63 (E63)   Car and Set Speed Tolerance Exceeded 
64 (E64)   Car Acceleration Exceeds Maximum Limit 
65 (E65)   Coolant Temperature Exceeds Maximum Limit   
66 (E66)   Engine RPM Exceeds Maximum Limit 
67 (E67)   Shorted Set Or Resume Circuit 
70   System Ready - Switch Tests 
71   Brake Light Switch 
72   ISC Throttle Switch 
73   Drive (ADL) Switch 
74   Back-Up Lamp Switch 
75   Cruise On/Off Circuit 
76   Set/Coast Circuit 
77   Resume/Acceleration Circuit 
78   Instant/Average MPG Button 
79   Reset MPG Button 
80   A/C Clutch Circuit 
88   Display Check (-.1.8.
90   System Ready To Display Engine Data 
95   System Ready for Acuator Cycling 
96   Actuator Cycling 
97   MD Cylinder Solenoid Cycling 
00   All Diagnostic Complete 

[J]

somtimes its not the Sensor but a wire going to a sensor once you narrow it down you can ohm out the wires  i know this is a lot but i hope it helps, Jessie

[Dennis DiNorcia]

After one week in the shop and $600.00, I got the car back fixed. Even though I only tuned up the car appx 25,000 miles ago, the shop did  full tune-up including wires, cap, module, air filter, fuel filter, etc. I don't know if it needed all that or was it just a trial and error situation. Anyway, the car starts and runs fine and no more hesitation. Thanks, for all the help given by CLC members.