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Mazda Miata 2000 P0102 P0123 P1771 - No Wheel Power, Stuttering at High Speeds After 2+ Hours of Driving

Model: Mazda Miata 2000 Fault Code: P0102 Posted: 2008-03-07 08:55

Hi everyone, I'm a DIYer with limited experience and need help diagnosing an issue on my 2000 Mazda Miata. The car runs smoothly initially with stable RPMs, but after driving for 2-3 hours—especially at speeds over 80 mph—it begins to lose power. The vehicle feels like it's losing traction, slowing down intermittently, and then resumes operation with a stuttering or jerking motion. The problem only occurs during extended highway drives and resolves itself after the car sits idle for 30 minutes or more—often lasting days or weeks without recurrence due to low usage. A previous dealer repair of the ignition coil did not resolve this issue. I've just pulled three OBD2 diagnostic codes: P0102 (Mass Airflow Sensor - MAF - low airflow), P0123 (Throttle Position Sensor - TPS - high input), and P1771 (TPS open or faulty signal to transmission control module). I've reviewed common causes, including EGR valve issues and aftermarket modifications, but I'm specifically looking for Mazda-specific insights on how these codes interact. The P1771 code is especially puzzling as it's not commonly discussed in general forums. Any advice or troubleshooting steps focused on the MAF, TPS wiring, or transmission communication would be greatly appreciated! Thanks in advance.

Related fault codes

P0102P0123P1771

Comments (7)

Anonymous 2008-03-07 09:43

Hi Gresh, Have you searched for solutions yet? Start with these OBD2 code references: https://www.obd-codes.com/p0102 https://www.obd-codes.com/p0123 Also check: search.php?keywords=p0102 and search.php?keywords=p0123. Begin by inspecting the wiring harnesses for both MAF and TPS sensors. Corrosion or loose connections are common culprits in these systems.

Anonymous 2008-03-07 14:32

I've done some research already. I'm now requesting the dealership to inspect the TPS and MAF sensor wiring, though their initial suggestion was a fuel pump—which didn't seem plausible given the symptoms. I reviewed the links you provided but noticed very limited Mazda-specific information on P1771. That's why I started this thread—there’s little guidance for this exact combination of codes in general forums. Will update as progress is made. Thanks!

Anonymous 2008-03-07 19:02

Don't forget to check the EGR valve—it's a known issue on older Mazda models. Also, confirm whether any aftermarket performance parts (like cold air intakes or power adders) have been installed recently, as these can interfere with sensor readings and throttle response.

Anonymous 2008-04-08 05:55

I own a 2001 MX-5 with identical symptoms. It runs fine for weeks, then suddenly starts stuttering, jerking, or stalling—especially at high speeds. Throttle response is delayed or absent. I’ve noticed a faint rotten egg smell, which may indicate excessive fuel in the exhaust (possible rich mixture). After letting it sit 5–10 minutes, it restarts smoothly and runs perfectly again for another couple of weeks. The check engine light comes on but clears after restarting. I've replaced plugs, air filter, and fuel filter; PCV valve checks out. No oil burning or dirty plugs—so the issue seems to be sensor-related rather than mechanical.

Anonymous 2008-04-08 07:15

On my Actron DTC lookup, P1771 is listed as 'Shift Solenoid E Performance Issue'. This could explain inconsistent TPS behavior and transmission communication problems. The shift solenoid may be malfunctioning or sending incorrect signals to the TPS module, leading to erratic throttle response and power loss at high speeds. This might be a key link between the P0123 and P1771 codes—worth investigating further.

Anonymous 2008-04-08 09:45

I'd prioritize checking the TPS first. You have two related codes: P0123 indicates high throttle position input, while P1771 may also reflect a high signal depending on interpretation. The MAF code (P0102) shows low airflow—this could suggest the ECU thinks there's less air than present. If the TPS reports an open or excessive throttle position, the ECU might misread engine load and reduce fuel delivery or power output, especially under sustained high-speed driving conditions.

Anonymous 2010-09-02 00:13

Hi there! Did you manage to resolve this issue? I'm experiencing similar symptoms on my Mazda Miata—especially with engine performance degradation after long drives. Any specific steps you took to fix it? Would really appreciate your insights or recommendations.