Help! I'm Stymied!, Only firing on #3 and # 4 |
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Help! I'm Stymied!, Only firing on #3 and # 4 |
DipShit |
Jun 12 2009, 10:19 AM
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#1
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Member Group: Members Posts: 199 Joined: 26-May 04 From: Cheyenne, WY Member No.: 2,107 |
1.7 D-Jet
Engine was running just great until about two weeks ago, sigh. Now only fires on # 3 and # 4. I have cleaned every connection including all grounds. And I mean cleaned them good! The elecrical appears to be just fine. I get a good noid light at both # 1 and # 2. The injectors have tested just fine as well (I'm getting about 7cc in 15 seconds). I have 40lbs of pressure the 1,2 rail. The spark plugs are getting juice and fire. I have installed new points, cleaned the triggers (which shouldn't have mattered because of the sequence) and set the dwell. I'm a tad under at 44 degrees, but again shouldn't keep # 1 and # 2 from firing. The timing has to be close as it runs really smooth for just two cylinders. If I pull the power to injector 3 or 4, I get a real good drop and she will die. If I pull 1 or 2 - no change. If I add propane to the intake, I get a good response in higher rpm. I had originally traced to the Temp II sensor and it failed, so I replaced it. A new one seemed to be the fix, but only for a moment. I have good fuel, spark and air - (IMG:style_emoticons/default/WTF.gif) I'm STYMIED (or just a REAL DIPSHIT) |
VaccaRabite |
Jun 26 2009, 11:37 AM
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#2
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En Garde! Group: Admin Posts: 13,465 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
Check compression with the engine warm (if possible) and the throttle wide open. The difference between a warm and cool engine would explain the 15psi loss (assuming the engine was warm when you tested it last time, and cool this time.)
Also, are the "100" and "95" cylinders the #1 & #2 cylinders? Do you have a leakdown tester? So, just to confirm: Your sparkplugs are known good, they are making spark, and they are not fouled. You plug wires are known good. You are getting fuel, and good spray from the injectors. You are making compression - at least enough compression to run (you should be able to run @90 psi compression) Your valves are correct. Your timing is correct. Your dwell is correct. Really DUMB question, but are you positive that you have the #1 plug wire going to the #1 plug, and not the #2 plug? |
DipShit |
Jun 26 2009, 12:02 PM
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#3
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Member Group: Members Posts: 199 Joined: 26-May 04 From: Cheyenne, WY Member No.: 2,107 |
Check compression with the engine warm (if possible) and the throttle wide open. The difference between a warm and cool engine would explain the 15psi loss (assuming the engine was warm when you tested it last time, and cool this time.) Also, are the "100" and "95" cylinders the #1 & #2 cylinders? No 1 & 2 are 110 Do you have a leakdown tester? Will be borrowing one soon! So, just to confirm: Your sparkplugs are known good, they are making spark, and they are not fouled. Yes, new plugs and making spark. You plug wires are known good. yes work on 3,4 but not 1,2 when tested. You are getting fuel, and good spray from the injectors. Yes You are making compression - at least enough compression to run (you should be able to run @90 psi compression) - Yes Your valves are correct. - Yes Your timing is correct. - Yes Your dwell is correct. 45 Degrees - could stand to go a couple more but good enough for now. Really DUMB question, but are you positive that you have the #1 plug wire going to the #1 plug, and not the #2 plug? - NOT DUMB - I thought the same thing last night and switch them just to keep my sanity, then put them back... 1, 2 |
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