Classic FAST Help Needed, will not start sporadically??
- Thread starter BIGONTS
- Start date
It has spark, but I will check again. Voltage is good at about 13+ Volts. New alt and battery. Injector harness plug shows 12V, but no pulse I think, which I need to verify injector firing. I do not smell gas in pipes??
Have you removed the cam sensor cap and checked if the small locating tab is busted or the screw loose?
Yes, did the RJC mod before putting the new motor in last year. It's tight.
no nothing like that, the key is interlocked by the column position. Have you check the orange fusible link the the ecm memory at the battery ?
Yes. Checked it. I can communicate with ecm when cranking. Shows rpm voltage etc..
I plan on trying that next to eliminate the fast ecm and harness from being bad. Have two stock computers on hand. Just need a chip for 83s. Only have them for 50s. Should start but run rough due to no maf. Thoughts? Leave mapsensor wired? Also I noticed some pink wire that's jumped for the fast in the main harness that ends up under the coil pack?
You must disconnect the map sensor, you will end up being super rich with that chip but it may run, you must use the maf sensor and the maf sensor signal wire is used for the map sensor, so you will end up wit no map signal when you unplug the wiring, and plug back in the MAF. You will also have to connect the pink /black wire at the injector connector back the way it was factory and disconnect the new pink wiring coming from the fast.
Something really odd just happen when I was testing everything. I do one thing, move wires, adjust whatever, each time try to start.
Here’s a step by step:
Keep you posted. Ideas?
Here’s a step by step:
- Two days ago a put a known new coil pack and module on and not start.
- Didn’t change anything try to start it, not start. Checked spark and fuel, it’s all good. When I crank, fuel psi is around 40 and jumps up a bit when cranking.
- I readjust the old AC Delco crank sensor and currently had in there, not start. Started 3 days ago. (The new AC Delco I broke trying to adjust, getting new one)
- Just for shits and giggles, I put back the old Standard crank sensor that I originally started with, not start.
- So I try to test if the injectors are firing, one way Lance told me.
- Turn key on, build fuel pressure, unplug fuel relay and crank,
- Fuel pressure should go down if injectors are firing, but fuel pressure not build up because pump is off
- I do that; unplug relay and the car starts for a second using up all fuel in lines??
- I look at the plug on the gray fuel relay, and it looks really dirty. Kind of sticky with black stuff on it. I assume it's factory lube?? I clean it just a bit; plug it in, car turns on???
Keep you posted. Ideas?
- Joined
- May 28, 2001
Time to clean and lube ALL connections you can get to...
Chuck Leeper said:
Yeah. Thought I inspected all of them when the motor was out. I had the car idling for about 20 min without it shutting off. Also moving all wires I can get my hand on at the same time. Also drove it up and down the block several times. For some reason I'm not 100% sure this was it, but it sure seems like it. How does this relay contribute to injector pulse? Also have a hotwire kit to the pump with a relay also. Will report back once I get some more time to drive it around. Thanks
Final update everyone, I'm hoping. I believe everything is solved for now. Car is starting without a problem the last 4 days, warm or cold. Drove the car around for about two hours last night without a hickup. I believe it was a combination of a coil module and crank sensor going bad and the fuel pump relay connection. The car runs so much smoother with new crank sensor and module.
Too bad I missed Cal's tuning session in Chicago. I might try to work something out remotely with him or a local tuner.
Thanks again everyone.
Too bad I missed Cal's tuning session in Chicago. I might try to work something out remotely with him or a local tuner.
Thanks again everyone.
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