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Gudhjem |
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#1
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Member ![]() ![]() Group: Members Posts: 133 Joined: 29-March 07 From: Castro Valley, CA Member No.: 7,629 Region Association: Northern California ![]() |
I've been trying to avoid posting this, since I figure everyone's tired of "my car wont start" posts. But, I've reached the end of my rope, I'm out of ideas, and I need some new ones.
I've got a '73 2.0, stock FI, except for a Crane x700 ignition. Sometimes it starts right up, but often, about half the time now, it wont. The starter cranks, turns over the engine very quickly, but the engine just wont "catch." It just keeps cranking. It acts as if I forgot the rotor or am out of gas (I didn't and I'm not). Happens warm and cold (though possibly more often warm). I can't think of anything I've done to the car that coudl cause this (no engine tinkering to speak of), and it seems to be getting worse. Today, it did the same thing and after cranking for about 15 seconds, seemed to backfire from inside the case. It blew off the little rubber fitting that sits next to the oil filler cap (the one I'm pointing to in the pic). This happened twice. The kicker is that once it starts, it runs like a champ. I mean really well - smooth all the way thorugh the range, plenty of power, no smoke out the exhaust, relatively smooth idle at about 800, etc. That forutnatly (or maybe unfortunatly) eliminates most of the reasons why a car wont start. I don't need to worry that my plug wires or injector leads are crossed, or that my plug wires are bad, or my coil is bad, or my Fireball isn't working, or my injectors are not squirting, or that I have no compression, or that I have no fuel pressure, or that my timing is way off, that I have a bad connection or ground somewhere, or that my dizzy is in backward. Here's what I've tried: checked timing checked fuel pressure (set it to 29lbs) verified spark at the plugs removed cold start valve wires replaced spark plugs (0.028") replaced coil (bosch blue) replaced spark plug wires replaced cap and rotor Seems to me that since it runs so well once started, the MPS and temp sensors or brain could not be the causes. It does look wet when I pear down the throttle body (inside the air distributor thing the throttle body sits on), and although the plugs I pulled were black and a little bit moist, they were not really fouled. So I have spark, I have timing, and I have fuel, I am suspicious that it must be a mixture thing, but don't know where to go with that, and again, it runs so well when it starts. Any ideas? --Steve ![]() |
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underthetire |
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#2
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,062 Joined: 7-October 08 From: Brentwood Member No.: 9,623 Region Association: Northern California ![]() |
No andy, actually you put the pedal to the floor while cranking. One shot before does nothing on a FI car. That is supposed to put it in flood clear mode, or at least lean out the mixture. Modern FI is for sure flood clear, gives no pulses to the injectors.
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SirAndy |
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#3
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Resident German ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Admin Posts: 42,257 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California ![]() |
No andy, actually you put the pedal to the floor while cranking. One shot before does nothing on a FI car. That is supposed to put it in flood clear mode, or at least lean out the mixture. Modern FI is for sure flood clear, gives no pulses to the injectors. Are you sure that's how D-Jet works? The one time down has always worked for me on my D-Jet motors ... Maybe i've just been lucky? (IMG:style_emoticons/default/idea.gif) Andy |
pbanders |
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#4
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Senior Member ![]() ![]() ![]() Group: Members Posts: 943 Joined: 11-June 03 From: Phoenix, AZ Member No.: 805 ![]() |
No andy, actually you put the pedal to the floor while cranking. One shot before does nothing on a FI car. That is supposed to put it in flood clear mode, or at least lean out the mixture. Modern FI is for sure flood clear, gives no pulses to the injectors. Are you sure that's how D-Jet works? The one time down has always worked for me on my D-Jet motors ... Maybe i've just been lucky? (IMG:style_emoticons/default/idea.gif) Andy underthetire is right, the owners manual actually tells you to put the pedal to the floor while cranking. Personally, when the car is set up correctly, I've never had to do this, in fact, it starts fine with the throttle completely closed. The reason I suggested opening the throttle with the igniton off, then cranking, is that if you open the throttle with the ignition on, you're shooting 10 ms worth of fuel into two of the intakes, due to the action of the TPS and the ECU. You can hear the injectors click as you do this in a quiet garage. If the car is already rich, more fuel isn't going to help. I think the reason Andy's method works is that many 914's are too lean on starting, so the extra fuel helps out. |
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