The “stomp test” is a simple procedure performed to determine the cause of a Check Engine Light (CEL) on a number of vehicles that used the Motronic 1.3 and 1.7 ECUs (such as the 1988-1992 E30 325i) and Motronic 3.x (such as 1991-1995 E36 325i). Motronic 1.3/1.7 ECUs include 173, 175, 179, 282, 380, 381, 524, 525, and 526. 3.x include 402, 403, 404, 413, and 506.
The procedure for performing the stomp test on Motronic 1.3/1.7 is as follows:
- Get in your vehicle and shut all doors/trunk.
- Turn key to “ON” position, but do not start the vehicle.
- Fully depress the accelerator pedal, then completely release for between 0.5 and 1.0 seconds. Repeat this a total of 5 times within 10 seconds.
- The CEL will flash once, then it will flash a Fehler Lampen Ort, or Fault Light Code (FLC).
- The code will flash as a succession of blinks, with a short pause between each number.
- eg. “blink-blink-pause, blink-pause, blink-blink-blink-pause, blink-pause” would be code “2-1-3-1”
- If there are no faults, it will flash the code “1444” (for 4, 6, and 8 cylinder engines) or “2444” (for 12 cylinder engines).
The procedure for performing the stomp test on Motronic 3.x is very similar, but differs in the following ways:
- The time between key and pedal action must be shorter.
- The pedal must be depressed, released, and repeated in quicker succession.
- It is a bit trickier and may take a few attempts.
The error codes are as follows:
| SYSTEM | CODE | NOTES |
| ECU | 1211 | ECU component failure or bad chip. |
| EGO(AFR) Sensor 2 | 1212 | |
| LAMBDA 2 | 1213 | |
| AIR FLOW METER | 1215 | |
| THROTTLE POSITION SENSOR | 1216 | |
| OUTPUT GROUP 1 | 1218 | |
| OUTPUT GROUP 2 | 1219 | |
| EGO(AFR) Sensor 1 | 1221 | |
| LAMBDA 1 | 1222 | |
| COOLANT TEMP SENSOR | 1223 | |
| INTAKE AIR TEMP SENSOR | 1224 | |
| KNOCK SENSOR 1 | 1225 | |
| KNOCK SENSOR 2 | 1226 | |
| KNOCK SENSOR 3 | 1227 | |
| KNOCK SENSOR 4 | 1228 | |
| BATTERY | 1231 | |
| TPS (IDLE SWITCH) | 1232 | |
| TPS (WIDE OPEN SWITCH) | 1233 | |
| SPEEDOMETER | 1234 | |
| A/C COMPRESSOR CUT OFF | 1237 | |
| A/C COMPRESSOR | 1242 | |
| CRANKSHAFT POSITION SENSOR | 1243 | |
| CAMSHAFT POSITION SENSOR | 1244 | |
| AUTOMATIC TRANSMISSION ERROR | 1245 | |
| IGNITION TIME MONITOR EXCEEDED | 1247 | |
| INJECTOR 1 (OR BANK 1) | 1251 | |
| INJECTOR 2 (OR BANK 2) | 1252 | |
| INJECTOR 3 | 1253 | |
| INJECTOR 4 | 1254 | |
| 5 | 1255 | |
| 6 | 1256 | |
| 7 | 1257 | |
| 8 | 1258 | |
| FUEL PUMP RELAY | 1261 | |
| IDLE ACTUATOR | 1262 | |
| PURGE VALVE | 1263 | |
| EGO HEATER | 1264 | |
| FAULT LAMP | 1265 | |
| VANOS | 1266 | |
| AIR PUMP RELAY | 1267 | |
| IGNITION COIL 1 | 1271 | |
| IGNITION COIL 2 | 1272 | |
| IGNITION COIL 3 | 1273 | |
| IGNITION COIL 4 | 1274 | |
| IGNITION COIL 5 | 1275 | |
| IGNITION COIL 6 | 1276 | |
| IGNITION COIL 7 | 1277 | |
| IGNITION COIL 8 | 1278 | |
| INTERNAL MEMORY ERROR | 1281 | |
| FAULT CODE MEMORY ERROR | 1282 | |
| INJECTION TIME OUTSIDE LIMITS | 1283 | |
| KNOCK CONTROL SYSTEM | 1286 | |
| No Failures | 1444 |