Intermittent Problem with Betty's car, I am at my wit's end on this one. |
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Intermittent Problem with Betty's car, I am at my wit's end on this one. |
ClayPerrine |
Dec 22 2014, 07:17 PM
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#1
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Life's been good to me so far..... Group: Admin Posts: 15,482 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
About 2 weeks ago, Betty came home and said her 74, 1.8L Ljet 914 was intermittently cutting out. I took it out to test drive it, and sure enough, it will randomly cut out. Sometimes mildly, sometimes it feels like the engine shuts off completely, then turns back on.
So I started troubleshooting. Nope, grounds for the injectors are fine. Put the LM-1 in the tailpipe and had her drive it. Every time it cuts out, the LM-1 shows it going lean. I put an L-Jet tester I have on it and ran through all the tests and it shows as working fine. I had it running in the garage, and I went through a "wiggle test", wiggling every wire and connection on the engine. Nothing I do can replicate the issue in the garage. So I started throwing parts at it. To date I have replaced: The air flow meter. The fuel injection wiring harness. The double relay. The dropping resistors. The fuel pump. The ECU. The CHT. The whole distributor with a different pertronix, and tried points too. Nothing I have done to date helps. So I am hoping the collective knowledge of this place will help. I have checked all the simple stuff already. This is going to be hard to fix, whatever it is. I am now to the (IMG:style_emoticons/default/WTF.gif) stage, and looking for suggestions. |
ClayPerrine |
Dec 27 2014, 10:06 PM
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#2
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Life's been good to me so far..... Group: Admin Posts: 15,482 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
Clay- disconnect the fuel line at the tb and stick the line in a bottle then have Betty turn the ignition on for a second. You should get a good flow which will rule out clogged line, pump, filter, crap in the tank, vacuum lock. Been over the whole fuel system. Replaced the pump, both fuel filters and all 4 injectors. Pulled the fuel sender and inspected inside the tank with a flashlight. Did you try grounding terminal III from the rear of the relay board ? This will eliminate the relay connection and wire- this test helped me the most. Also, forgot this one; is the relay ground wire firmly attached ? I've knocked this loose when reaching in to clean the case. The relays on the relay board do nothing for the fuel injection on an L-Jet car. I checked the grounds under the intake 3 times now. I may have missed this in all the posts, isn't there a ground wire for the breaker point mounting plate?? I had that break on an MG, took a while to figure that out.. I swapped out the distributor. This morning I pulled the steering column apart and replaced the ignition switch. Tried to start the car and it wouldn't crank. Put the old switch back in and it would crank. The brand new in the box ignition switch is bad. I have to go buy a new one on Monday. So I hung the wires below the dash, and used a screwdriver to turn the electrical portion of the ignition switch. Drove it around the neighborhood beating and wiggling the switch and the wires. No correlation between that and the cutting out. Update on what has been replaced: 1. Air flow meter 2. Complete L-Jet wiring harness. 3. ECU 4. Double relay. 5. Dropping resistors. 6. All 4 injectors. 7. Cylinder head temp sender. 8. Distributor, complete with pertronix unit (tried a set of points too). 9. Distributor cap and rotor. 10. Plug wires. 11. Fuel Pump 12. Front fuel filter in front of the pump (substitute for tank sock. The car doesn't have one any more and hasn't had one for years). 13. Rear fuel filter. 14. Opened tank and inspected the inside. Nothing visible inside. 15. Added dry gas to remove any possible water in the tank. Trying right now to replace the ignition switch too. (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) |
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