Posted November 16, 20204 yr comment_610513 Hi all First off I'd like to say this is a great forum and it's helped me a lot! This problem though I couldn't find in the search.... So I have a 1978 z pretty much all stock and it's been sitting in the garage for almost 30 years. I've been working on it the past month. I'm switching out a cheap fuel pump I put in just to see if I could get it up and running. It did but fuel pressure is low. I really think the pump is gummed up, the gas was nasty in the tank and even after siphoning it out I think everything is just coated with gunk. So anyway, I'm jumping the cold start vale terminal to depressurize the line, which I have done over the past month without an issue, but this time the engine is turning over! I've had the fuel relays, ignition relay out to clean and check. Could one of them be bad or shorted causing this issue? Any ideas would be great. Edited November 16, 20204 yr by jelp2 Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/ Share on other sites More sharing options...
November 16, 20204 yr comment_610515 don't understand what you are saying. Jumping the cold start vale terminal? the engine is turning over? you mean something your are doing is causing the starter to engage? It maybe possible to energize the starter solenoid by applying power to the positive side of the harness that plugs into the CSV I suppose, IIRC they share a common lug on the ign switch "start". But if that is what you are doing that is the incorrect way to activate the CSV to depressurize, You only want to apply power to the csv, not the harness, and frankly you don't need to do that, just put a rag around the fuel line at the fuel rail and loosen the hose clamp. there is not that much fuel stored, the rag will catch it and keep it from spraying. Edited November 16, 20204 yr by Dave WM Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610515 Share on other sites More sharing options...
November 16, 20204 yr comment_610516 What is the issue? The csv is like a short run fuel injector for adding fuel on start up. Are you getting to much fuel, not enough? You can unhook by pulling the electrical plug off or plug the fuel line to it also. Where I live it's warm enough that I have mine deleted. Car cranks and runs fine. Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610516 Share on other sites More sharing options...
November 16, 20204 yr Author comment_610517 What I'm trying to do is just depressurize the fuel line by jumping the terminal plug of the cold start valve so I can do some work on the fuel lines. The engine shouldn't crank when jumping the cold start valve plug, it should just click and release pressure, not crank the engine. So I don't know if there's a short somewhere or a faulty relay that's causing the engine to crank. Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610517 Share on other sites More sharing options...
November 16, 20204 yr comment_610518 You could pull the coil wire. No start for sure. I always wrap a towel and pull the fuel filter hose up front, fyi. Edited November 16, 20204 yr by siteunseen Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610518 Share on other sites More sharing options...
November 16, 20204 yr Author comment_610520 3 minutes ago, siteunseen said: You could pull the coil wire. No start for sure. I always wrap a towel and pull the fuel filter hose up front, fyi. I Have pulled the filter hose with a rag as my main method, I'm trying to go by the book this time. Lol My worry is if there's a short or a bad relay ( stuck open/closed) that's turning the engine that that could be a problem in the near future. I'm no good with wiring and relays and was hoping someone had a similar issue with a remedy. Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610520 Share on other sites More sharing options...
November 16, 20204 yr comment_610521 10 minutes ago, jelp2 said: What I'm trying to do is just depressurize the fuel line by jumping the terminal plug of the cold start valve Describe this "jumping" procedure. I don't think that that's standard practice. Sounds like you're causing a dead short across a plug that expects a load. Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610521 Share on other sites More sharing options...
November 16, 20204 yr comment_610522 Here is standard practice. If you do this without disconnecting the plug you might be backfeeding the ignition switch or some odd thing. Maybe you had the key On whereas before the key was off. Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610522 Share on other sites More sharing options...
November 16, 20204 yr comment_610523 Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610523 Share on other sites More sharing options...
November 16, 20204 yr Author comment_610524 15 minutes ago, Zed Head said: Here is standard practice. If you do this without disconnecting the plug you might be backfeeding the ignition switch or some odd thing. Maybe you had the key On whereas before the key was off. Oohhh sh*#*#* that's showing the terminals on the cold start valve itself. I must have been inhaling too many gas fumes! I was touching my jumper wires to the plug not the terminals on the cold start valve! The scary thing is, is I've done this correctly many times. Thank you Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610524 Share on other sites More sharing options...
November 16, 20204 yr comment_610525 Maybe you've discovered a built-in remote starter switch. Who wants to explore this further? Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610525 Share on other sites More sharing options...
November 16, 20204 yr Author comment_610526 Just now, Zed Head said: Maybe you've discovered a built-in remote starter switch. Who wants to explore this further? Lol. I was thinking that, could come in handy for sure. Link to comment https://www.classiczcars.com/forums/topic/64734-jumping-cold-start-valve-turns-engine-over/#findComment-610526 Share on other sites More sharing options...
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