In Emergency Peugeot 306 HDI

Hello friends, I have a Peugeot 306 HDI that won't let me accelerate past 1500 RPM. This is a typical problem with the fuel injection system; the check engine light stays on permanently, even when I turn the key to start the engine. It starts but won't shut off, and it's running rough, meaning it's straining. I know that people from Spain on this forum have been working on these types of engines for a long time. My question is, how and where can I measure the fuel pressure, the valve at the pump outlet, or the sensor on the fuel rail? The injection system is Bosch.
I tried another mass airflow sensor and a new EGR valve that I had at the garage, but nothing changed.
Hoping for some help, Regards, Julio

Hi, how are you? Based on what it's doing, don't overthink it. Go straight to the pressure sensor, remove it, and test it with a multimeter. Or, try replacing the pressure sensor with a new one and see what happens. I hope you can fix it. Best regards!
Diesel Simón -
Pablo Simón, Eduardo Castex, La Pampa, Argentina

Thanks for the quick reply. You're saying I should test the sensor on the ramp? It has three pins. How and what kind of test should I do? Do you know the resistance values, or should I check for continuity? I removed it and have it in my hand. I also removed the valve behind the high-pressure pump, which has two pins. Can that be tested? Best regards, Julio

Hi, how's it going? The only way to test the pressure valve is with a pulse generator, because it works with current pulses. Don't even think about applying 12V to it, haha. As for the pressure sensor, you can test its continuity or simply try a new one; they're not expensive. Well, I hope this helps. Cheers! Pablo Simón

Thanks for the reply. The check engine light never goes off, and now it won't start at all; I'm not getting any injection pulses. If I keep it running with starting fluid through the air filter hose, it stays running. The injector is getting 7V, and diesel is reaching the fuel lines, but it won't start. It's like it's not receiving any injection pulses. When it does start, it idles but doesn't accelerate at all. Could it be the relay behind the ECU? I look forward to your reply, and thanks again. JULIO