diff --git a/selfdrive/debug/internal/run_paramsd_on_route.py b/selfdrive/debug/internal/run_paramsd_on_route.py
new file mode 100755
index 0000000000..1e633bdce1
--- /dev/null
+++ b/selfdrive/debug/internal/run_paramsd_on_route.py
@@ -0,0 +1,149 @@
+#!/usr/bin/env python3
+# pylint: skip-file
+# flake8: noqa
+# type: ignore
+
+import math
+import multiprocessing
+
+import numpy as np
+from tqdm import tqdm
+
+from selfdrive.locationd.paramsd import ParamsLearner, States
+from tools.lib.logreader import LogReader
+from tools.lib.route import Route
+
+ROUTE = "b2f1615665781088|2021-03-14--17-27-47"
+PLOT = True
+
+
+def load_segment(segment_name):
+  print(f"Loading {segment_name}")
+  if segment_name is None:
+    return []
+
+  try:
+    return list(LogReader(segment_name))
+  except ValueError as e:
+    print(f"Error parsing {segment_name}: {e}")
+    return []
+
+
+if __name__ == "__main__":
+  route = Route(ROUTE)
+
+  msgs = []
+  with multiprocessing.Pool(24) as pool:
+    for d in pool.map(load_segment, route.log_paths()):
+      msgs += d
+
+  for m in msgs:
+    if m.which() == 'carParams':
+      CP = m.carParams
+      break
+
+  params = {
+    'carFingerprint': CP.carFingerprint,
+    'steerRatio': CP.steerRatio,
+    'stiffnessFactor': 1.0,
+    'angleOffsetAverageDeg': 0.0,
+  }
+
+  for m in msgs:
+    if m.which() == 'liveParameters':
+      params['steerRatio'] = m.liveParameters.steerRatio
+      params['angleOffsetAverageDeg'] = m.liveParameters.angleOffsetAverageDeg
+      break
+
+  for m in msgs:
+    if m.which() == 'carState':
+      last_carstate = m
+      break
+
+  print(params)
+  learner = ParamsLearner(CP, params['steerRatio'], params['stiffnessFactor'], math.radians(params['angleOffsetAverageDeg']))
+  msgs = [m for m in tqdm(msgs) if m.which() in ('liveLocationKalman', 'carState', 'liveParameters')]
+
+  ts = []
+  ts_log = []
+  results = []
+  results_log = []
+  for m in tqdm(msgs):
+    if m.which() == 'carState':
+      last_carstate = m
+
+    elif m.which() == 'liveLocationKalman':
+      t = last_carstate.logMonoTime / 1e9
+      learner.handle_log(t, 'carState', last_carstate.carState)
+
+      t = m.logMonoTime / 1e9
+      learner.handle_log(t, 'liveLocationKalman', m.liveLocationKalman)
+
+      x = learner.kf.x
+      sr = float(x[States.STEER_RATIO])
+      st = float(x[States.STIFFNESS])
+      ao_avg = math.degrees(x[States.ANGLE_OFFSET])
+      ao = ao_avg + math.degrees(x[States.ANGLE_OFFSET_FAST])
+      r = [sr, st, ao_avg, ao]
+      if any(math.isnan(v) for v in r):
+        print("NaN", t)
+
+      ts.append(t)
+      results.append(r)
+
+    elif m.which() == 'liveParameters':
+      t = m.logMonoTime / 1e9
+      mm = m.liveParameters
+
+      r = [mm.steerRatio, mm.stiffnessFactor, mm.angleOffsetAverageDeg, mm.angleOffsetDeg]
+      if any(math.isnan(v) for v in r):
+        print("NaN in log", t)
+      ts_log.append(t)
+      results_log.append(r)
+
+  results = np.asarray(results)
+  results_log = np.asarray(results_log)
+
+  if PLOT:
+    import matplotlib.pyplot as plt
+    plt.figure()
+
+    plt.subplot(3, 2, 1)
+    plt.plot(ts, results[:, 0], label='Steer Ratio')
+    plt.grid()
+    plt.ylim([0, 20])
+    plt.legend()
+
+    plt.subplot(3, 2, 3)
+    plt.plot(ts, results[:, 1], label='Stiffness')
+    plt.ylim([0, 2])
+    plt.grid()
+    plt.legend()
+
+    plt.subplot(3, 2, 5)
+    plt.plot(ts, results[:, 2], label='Angle offset (average)')
+    plt.plot(ts, results[:, 3], label='Angle offset (instant)')
+    plt.ylim([-5, 5])
+    plt.grid()
+    plt.legend()
+
+    plt.subplot(3, 2, 2)
+    plt.plot(ts_log, results_log[:, 0], label='Steer Ratio')
+    plt.grid()
+    plt.ylim([0, 20])
+    plt.legend()
+
+    plt.subplot(3, 2, 4)
+    plt.plot(ts_log, results_log[:, 1], label='Stiffness')
+    plt.ylim([0, 2])
+    plt.grid()
+    plt.legend()
+
+    plt.subplot(3, 2, 6)
+    plt.plot(ts_log, results_log[:, 2], label='Angle offset (average)')
+    plt.plot(ts_log, results_log[:, 3], label='Angle offset (instant)')
+    plt.ylim([-5, 5])
+    plt.grid()
+    plt.legend()
+    plt.show()
+