improving my startup
#1
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I am terribly noob, but I've noticed when my car is "cold starting" (granted it's not very cold around here yet...) but after it's sat a few hours or overnight, it has a terrible time starting. Usually it will turn and run for half a second and stall if I hit the gas. Also it likes to do half a crank and "freeze up"... but it will start like normal after a couple turns of the key.
I've been trying to find threads and topics about crank pulse and priming pulse etc... but I can't find anything that actually helps me understand what these are and how they work, so that I might play with them until the car starts better...
thanks for any help/explaination/tutoring....
I've been trying to find threads and topics about crank pulse and priming pulse etc... but I can't find anything that actually helps me understand what these are and how they work, so that I might play with them until the car starts better...
thanks for any help/explaination/tutoring....
#5
Cpt. Slow
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I'm game for answers as well.
Have you tried jumping it with another battery? Mine has the exact same issues and a very old battery. Ive been wonder if the starter, coils, etc aren't getting enough juice after it's sat for a while.
Have you tried jumping it with another battery? Mine has the exact same issues and a very old battery. Ive been wonder if the starter, coils, etc aren't getting enough juice after it's sat for a while.
#7
Boost Czar
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I am terribly noob, but I've noticed when my car is "cold starting" (granted it's not very cold around here yet...) but after it's sat a few hours or overnight, it has a terrible time starting. Usually it will turn and run for half a second and stall if I hit the gas. Also it likes to do half a crank and "freeze up"... but it will start like normal after a couple turns of the key.
I've been trying to find threads and topics about crank pulse and priming pulse etc... but I can't find anything that actually helps me understand what these are and how they work, so that I might play with them until the car starts better...
thanks for any help/explaination/tutoring....
I've been trying to find threads and topics about crank pulse and priming pulse etc... but I can't find anything that actually helps me understand what these are and how they work, so that I might play with them until the car starts better...
thanks for any help/explaination/tutoring....
So, tune your cranking pulse table?
Let me break it down very simply. Up means More, Down means Less.
It's plotted against CLT and pulses.
So at a given CLT temp you can inject more or less fuel during cranking.
so, drop the value really low at your temp that's given you issue, and crank. if it doesnt start, increase the number. Do it until the car starts.
Congratulations, you've learned how to tune.
#8
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I have had starting issues for a while as well. I mostly understand the principals of tuning the MS under startup, which leads me to believe there may be another problem.
Has anyone toyed with the idea that the alternator circuit for the NB is a problem, since it tries to charge the battery while cranking? I tried starting my car without the Alt/WP belt and it seemed like it took a lot less fuel to start, but that is to be expected. Anyone experimented with an RPM based trigger using one of the outputs from the MS?
Also, I had a problem with alternator belt slip right after starting, that was non-existent with the OEM ECU. A new belt and some more tension solved it, but it kind of pointed to a lot of drag from the alternator.
Has anyone toyed with the idea that the alternator circuit for the NB is a problem, since it tries to charge the battery while cranking? I tried starting my car without the Alt/WP belt and it seemed like it took a lot less fuel to start, but that is to be expected. Anyone experimented with an RPM based trigger using one of the outputs from the MS?
Also, I had a problem with alternator belt slip right after starting, that was non-existent with the OEM ECU. A new belt and some more tension solved it, but it kind of pointed to a lot of drag from the alternator.
#10
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I have had starting issues for a while as well. I mostly understand the principals of tuning the MS under startup, which leads me to believe there may be another problem.
Has anyone toyed with the idea that the alternator circuit for the NB is a problem, since it tries to charge the battery while cranking? I tried starting my car without the Alt/WP belt and it seemed like it took a lot less fuel to start, but that is to be expected. Anyone experimented with an RPM based trigger using one of the outputs from the MS?
Also, I had a problem with alternator belt slip right after starting, that was non-existent with the OEM ECU. A new belt and some more tension solved it, but it kind of pointed to a lot of drag from the alternator.
Has anyone toyed with the idea that the alternator circuit for the NB is a problem, since it tries to charge the battery while cranking? I tried starting my car without the Alt/WP belt and it seemed like it took a lot less fuel to start, but that is to be expected. Anyone experimented with an RPM based trigger using one of the outputs from the MS?
Also, I had a problem with alternator belt slip right after starting, that was non-existent with the OEM ECU. A new belt and some more tension solved it, but it kind of pointed to a lot of drag from the alternator.
- Tom
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09-05-2015 08:02 AM