Help needed: Intermittent dying/no start condition
12-03-2006, 11:04 PM
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Help needed: Intermittent dying/no start condition Hey guys,
Car is a stock 99 Formula.
I was hoping someone could help me with a weird problem I have been chasing on my stock 99 Formula for a few weeks. It all started at an auto-x 3 weeks ago. During my second run, the car died on course. I was at full throttle, and it just died. After approx 5-8 secs of cranking, it fired up, and I finished the run. It had over 3/4 tank of gas at the time. On my next run, it seemed to 'cut out' for a second several times, but never died. Car ran fine on last run, and I drove home without problems.
The next day, it died on me driving to school, and wouldn't restart. I pushed the valve on the fuel rail, and virtually no fuel came out. I had the car towed home. After getting it home, of course, it started right up. I was driving the next day, and the car died again. This time, however, I had a fuel pressure gauge with me. I checked the fuel pressure, and it was zero. The fuel pump was not priming.
Got the car home, dropped the tank a few days later, and checked for power at the pump. There was power at the pump, although I hadn't tried to start it that day. I replaced the pump, and it started right up. A test drive that night went perfectly. The next day it died on me again. Again, the fuel pressure gauge showed zero fuel pressure.
I check to see if the relay is getting power. It is getting a constant hot, but no signal. Swapping the fuel pump relay with the A/C relay didn't fix it. I jump the relay with a piece of wire, and the fuel pressure goes up as expected, BUT IT STILL WON'T START!
After sitting a while, the car would start right up again, and then after letting it sit and going back to start it one more time, it won't start. Currently, the car won't start and has no spark. The fuel pump isn't priming when you turn the key to the on position, as the relay isn't getting a signal. I don't know if the injectors are firing, but I would guess no.
This sounds like a crank position sensor problem, EXCEPT even with a bad crank position sensor, it should still prime the fuel pump (I assume). This leads me to believe it is a bad PCM. However, I swapped my PCM with a known good one, and it still wouldn't start.
No check engine light. No security light. Car always turns over. How would you check the BCM?
Anyone have any tech on this? What does the comptuer need to see before it will enable the fuel pump to run and fire the spark plugs?
Car is a stock 99 Formula.
I was hoping someone could help me with a weird problem I have been chasing on my stock 99 Formula for a few weeks. It all started at an auto-x 3 weeks ago. During my second run, the car died on course. I was at full throttle, and it just died. After approx 5-8 secs of cranking, it fired up, and I finished the run. It had over 3/4 tank of gas at the time. On my next run, it seemed to 'cut out' for a second several times, but never died. Car ran fine on last run, and I drove home without problems.
The next day, it died on me driving to school, and wouldn't restart. I pushed the valve on the fuel rail, and virtually no fuel came out. I had the car towed home. After getting it home, of course, it started right up. I was driving the next day, and the car died again. This time, however, I had a fuel pressure gauge with me. I checked the fuel pressure, and it was zero. The fuel pump was not priming.
Got the car home, dropped the tank a few days later, and checked for power at the pump. There was power at the pump, although I hadn't tried to start it that day. I replaced the pump, and it started right up. A test drive that night went perfectly. The next day it died on me again. Again, the fuel pressure gauge showed zero fuel pressure.
I check to see if the relay is getting power. It is getting a constant hot, but no signal. Swapping the fuel pump relay with the A/C relay didn't fix it. I jump the relay with a piece of wire, and the fuel pressure goes up as expected, BUT IT STILL WON'T START!
After sitting a while, the car would start right up again, and then after letting it sit and going back to start it one more time, it won't start. Currently, the car won't start and has no spark. The fuel pump isn't priming when you turn the key to the on position, as the relay isn't getting a signal. I don't know if the injectors are firing, but I would guess no.
This sounds like a crank position sensor problem, EXCEPT even with a bad crank position sensor, it should still prime the fuel pump (I assume). This leads me to believe it is a bad PCM. However, I swapped my PCM with a known good one, and it still wouldn't start.
No check engine light. No security light. Car always turns over. How would you check the BCM?
Anyone have any tech on this? What does the comptuer need to see before it will enable the fuel pump to run and fire the spark plugs?
