oldie but...

[kev2]

helping on a 1983 coupe deville, yes 83. looking for diagnostic info for a code 33.

I ahve gotten different descriptions for code- SO looking for a good lead, and a trouble tree if available.

MIL is on, runs rrrrrough

[Cadillac Jim]

Cadillacs have had OBD I since 1981. In fact, OBD is a Cadillac/GM concept that is now required on all cars sold in the USA.

That isn't all of the code. Possibilities are

I033 Loss of Supplemental Inflatable Restraint Data

T033 RR Wheel Speed Sensor Continuity Fault

R033 Steering Diode Shorted in Arming Sensor

T033 RR Wheel Speed Sensor Continuity Fault

P033 (E033) Wheel speed sensors problem

Also, which are current, if any, and which are stored as history is important too. The I and R codes are air bag codes. The others are rear wheel speed sensor faults. Try to get us the rest of the code. If there isn't any more information, then tell us what comes up before and after the code. If you have other lights, like an air bag or ABS light, or a Check Engine light, that will tell us more, too. Drivability issues, like the ABS doesn't work, will tell more, too.

If the code has been there since you got the car, it's possible that an air bag is bad, or that the air bag system has been disconnected (the I033 code is an air bag network code).

My money is a loose wiring connector on the right rear wheel speed sensor, and the P033 is why the MIL is on.

As for the rough running, I would check the distributor cap and rotor; if cleaning out the distributor cap helps at all I would change the cap and rotor. If that doesn't do it all, I would change the spark plugs, and if that doesn't do it I would change the plug wires. I'm assuming that you have an HEI with magnetic pickup, and no points or condenser. If the rough running persists after cleaning up the ignition, have the ignition checked to make sure your coils aren't breaking down. If everything is OK with the ignition then you can clean the fuel injectors and check the fuel pressure.

As a casual Tuesday-after-work thing, I would clean out the distributor cap with a paper towel, change the plugs, and put STP injector cleaner in the gas.

[kev2]

I will 'double' check for those Alpha designators (T-R-etc) and post them,

But would so called :body code" set MIL?

[jackc]

Here's a listing of 2 digit GM trouble codes. 33 looks like a MAP or MAF problem, which could be consistent with running rough.

http://www.obd-codes.com/trouble_codes/gm/...digit-codes.php

[KHE]

Cadillacs have had OBD I since 1981. In fact, OBD is a Cadillac/GM concept that is now required on all cars sold in the USA.

That isn't all of the code. Possibilities are

I033 Loss of Supplemental Inflatable Restraint Data

T033 RR Wheel Speed Sensor Continuity Fault

R033 Steering Diode Shorted in Arming Sensor

T033 RR Wheel Speed Sensor Continuity Fault

P033 (E033) Wheel speed sensors problem

Also, which are current, if any, and which are stored as history is important too. The I and R codes are air bag codes. The others are rear wheel speed sensor faults. Try to get us the rest of the code. If there isn't any more information, then tell us what comes up before and after the code. If you have other lights, like an air bag or ABS light, or a Check Engine light, that will tell us more, too. Drivability issues, like the ABS doesn't work, will tell more, too.

If the code has been there since you got the car, it's possible that an air bag is bad, or that the air bag system has been disconnected (the I033 code is an air bag network code).

My money is a loose wiring connector on the right rear wheel speed sensor, and the P033 is why the MIL is on.

As for the rough running, I would check the distributor cap and rotor; if cleaning out the distributor cap helps at all I would change the cap and rotor. If that doesn't do it all, I would change the spark plugs, and if that doesn't do it I would change the plug wires. I'm assuming that you have an HEI with magnetic pickup, and no points or condenser. If the rough running persists after cleaning up the ignition, have the ignition checked to make sure your coils aren't breaking down. If everything is OK with the ignition then you can clean the fuel injectors and check the fuel pressure.

As a casual Tuesday-after-work thing, I would clean out the distributor cap with a paper towel, change the plugs, and put STP injector cleaner in the gas.

None of those code descriptions apply to a 1983 model... a 1983 model did not have air bags or ABS. Code 33 on a HT-4100 engine is the MAP/BARO sensor correlation code. Check the vacuum line that is under the throttle body - where the hard plastic line uses a rubber section of hose to join it to the port on the throttle body. After many years, the rubber hose coupling cracks and a vacuum leak results.

[Cadillac Jim]

What they said.