mpowerdave
11-24-2007, 03:47 AM
So, she died and won't start... :shifty
Over the past few weeks I've have several instances where the car (98 528i 160k) would stumble for a second or two and then come back on. A couple times the motor actually stalled, but would easily restart. I got more serious into diagnosing it earlier this week and tried reading the codes. Nothing on the OBD II interface. Carsoft came back with a bad ASC "gas valve throttle sensor". The DME was clean. This made a little sense as I thought the ASC might be thinking that the throttle is in the wrong position and might be trying to close the throttle. Made perfect sense except that I don't think a fully closed ASC throttle should stall the motor... Anyways, I disconnected the sensor which forced an ASC fault and the problem appeared to have gone away. Except for today when I encountered a couple short blips/stumbles from the motor. The engine was cold so I sorta dismissed it. Except for tonight while driving home, the motor up and died and would simply not restart. I tried to do as much as I could on the side of the road - disconnected and reconnected various harness connectors. I managed to get the cap off the fuel schrader valve and found what appeared to be plenty of fuel pressure. I wrapped on the cam sensor and fuel pump with a screwdriver. Nothing except on one attempt the motor almost reved up to idle with my foot on the floor, but then died. Every other attempt was with the motor quickly spinning over, but no "pop". So I eventually gave up and had it towed home. After the tow, I tried again and it still wouldn't start.
Any ideas on what I should start looking for? Ohms across the cam sensor might be the first thing to check. Second might be confirming that the fuel pump works. I'll try to read codes again, but I think it will come back clean like the first time. What other things could cause a completely dead motor? Hopefully it stays dead. I'll be a little upset if it fires right up tomorrow morning.
:help
Over the past few weeks I've have several instances where the car (98 528i 160k) would stumble for a second or two and then come back on. A couple times the motor actually stalled, but would easily restart. I got more serious into diagnosing it earlier this week and tried reading the codes. Nothing on the OBD II interface. Carsoft came back with a bad ASC "gas valve throttle sensor". The DME was clean. This made a little sense as I thought the ASC might be thinking that the throttle is in the wrong position and might be trying to close the throttle. Made perfect sense except that I don't think a fully closed ASC throttle should stall the motor... Anyways, I disconnected the sensor which forced an ASC fault and the problem appeared to have gone away. Except for today when I encountered a couple short blips/stumbles from the motor. The engine was cold so I sorta dismissed it. Except for tonight while driving home, the motor up and died and would simply not restart. I tried to do as much as I could on the side of the road - disconnected and reconnected various harness connectors. I managed to get the cap off the fuel schrader valve and found what appeared to be plenty of fuel pressure. I wrapped on the cam sensor and fuel pump with a screwdriver. Nothing except on one attempt the motor almost reved up to idle with my foot on the floor, but then died. Every other attempt was with the motor quickly spinning over, but no "pop". So I eventually gave up and had it towed home. After the tow, I tried again and it still wouldn't start.
Any ideas on what I should start looking for? Ohms across the cam sensor might be the first thing to check. Second might be confirming that the fuel pump works. I'll try to read codes again, but I think it will come back clean like the first time. What other things could cause a completely dead motor? Hopefully it stays dead. I'll be a little upset if it fires right up tomorrow morning.
:help