Won't Run, New Info |
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Won't Run, New Info |
JC 914 |
Oct 15 2007, 12:17 PM
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#1
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Member Group: Members Posts: 124 Joined: 21-June 07 From: Johnson City,TN Member No.: 7,827 |
OK Here goes!!!! The wife and I decide to take a nice mountain drive Sunday after my mechanic (Porsche race car certified) gave me a clean bill of health for my '74 2.0 liter. Drove about forty miles through some of the most beautiful country (near ski slopes), and decided to stop for early dinner. Fabulous outdoor dining, temp about 76, several adult beverages, you know!!!! Got back iin the car to leave dead fuel pump
Left car at the only garage in town, daughter came and got us. Next morning, called Nate in Sacramento(THANKS, NATE!!) He overnighted a fuel pump directly to the garage, DUMBASS installed it, and called to tell me it was ready, but it didn't run just right Long story short, had car towed to my guy (sixty miles), who discovered that DUMBASS had not only kinked the fuel line, but didn't reinstall the fuel filter!!!!!!Who knows what got into my injectors Update soon!!!!!!!!! NOW WHAT??? After three weeks in the shop, running down all the FI components electrically, I'm getting no pulse to the fuel injectors. We even tried replacing the computer with a known working one. HELP!!!!!!!!! |
toon1 |
Oct 21 2007, 01:00 AM
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#2
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Senior Member Group: Members Posts: 1,849 Joined: 29-October 05 From: tracy,ca Member No.: 5,022 |
How are you determining that the pulse to the injectors is 'very weak'? Toons right on with the squirt in the jar thing - it will tell you a lot. I'm really a strong believer in the usefullness of measuring everything possible at the wiring harness of the ECU. That way you can be assured that the all the components are giving (more or less) the correct signal to the ECU. Given that it will start initially you know that your compression, spark and basic fuel delivery is all good. What you have is a failure in the metering system. By the way, it is unlikely that the cold start valve is what is giving you that burst at startup. It does not cut in until very low temperatures. When you key on all four injectors get a pulse. If you listen closely you'll hear them. That is what is giving you the start. The injectors also get an enrichment pulse as you move the throttle. What happens if you feather the throttle when you first start it - will it keep trying to run (poorly). good points, BTW you will see a week signal anyway if you check the elec. pulse at the inj.. It does'nt take much to activate them. It still sounds like there is a fuel clog somewhere |
swl |
Oct 21 2007, 07:53 AM
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#3
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Senior Member Group: Members Posts: 1,409 Joined: 7-August 05 From: Kingston,On,Canada Member No.: 4,550 Region Association: Canada |
It still sounds like there is a fuel clog somewhere Given the history of the failure that makes good sense. Perhaps a kinked line on the HP side of the pump that tightens as the fuel pressure builds. Enough pressure for the first bang but pressure drops off immediately. |
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