IncompetentOne Posted May 15, 2013 Share Posted May 15, 2013 1977 280z 2+2 non Cali model (n42 head and block) For starters: I do have the manuals for the car and have read the sections many times. But some questions I had just weren't answered there so here we go. -There is a vacuum hose leading from the distributor to a little cylinder with the other hose going to the carbon canister, is this needed of can I just plug off the hole. If it is needed, what do the two wires coming from the small cylinder plug into? -Also, when the engine is at TDC with the distributor on, it points directly toward the front of the car, right on top of the cylinder that is supposed to fire first. is this correct or way off? I thought that the rotor had to start before the first cylinder? - I have tried to start the car many times within the past few weeks but it wont even pop once or twice. I took the plugs out today and they are perfectly clean, and barely even smell of gas. So I assume the injectors are not doing their job properly. I saw on someones build that they had to sauder the connection together in the air flow meter because it was not telling the car to open the injectors. Thank you in advance for any comments Quote Link to comment Share on other sites More sharing options...
twofouroh Posted May 15, 2013 Share Posted May 15, 2013 (edited) -There is a vacuum hose leading from the distributor to a little cylinder with the other hose going to the carbon canister, is this needed of can I just plug off the hole. If it is needed, what do the two wires coming from the small cylinder plug into? Not important to get it running. It's the vacuum advance line. Check your FSM for vacuum hose routing, and make sure all are properly connected or properly blocked off - vac leaks suck . . . . . -Also, when the engine is at TDC with the distributor on, it points directly toward the front of the car, right on top of the cylinder that is supposed to fire first. is this correct or way off? I thought that the rotor had to start before the first cylinder? It should be pointing at the #1 spark tower on the cap, which is usually towards the front of the cap. Also make sure the wires are stitched up to the right cylinders (FSM again). - I have tried to start the car many times within the past few weeks but it wont even pop once or twice. I took the plugs out today and they are perfectly clean, and barely even smell of gas. So I assume the injectors are not doing their job properly. I saw on someones build that they had to sauder the connection together in the air flow meter because it was not telling the car to open the injectors. The plugs (and exhaust) should reek of gas after cranking without it starting. Before you dive off into the 'heaven' of troubleshooting the FI system, hit all the basics first!! Probably need to check whether it's getting any/enough gas. Fuel pump running? Fuel filters clogged? Is the gas fresh? Old gas is harder to burn. Does gas come out of the fuel rail when disconnected? Are the injector electrical connectors making good contact? Ford Duratec motors have good injector connectors for a cheap junkyard replacement. Clean all the engine connectors while you're at it. Check timing & compression? Autozone has timing lights & compression checkers as loaner tools. Get a can of carb cleaner and spray it straight into the intake plenum for about 2-3 seconds through one of the vacuum bungs. The ignition on a 78 is separate from the FI system, so the car should run for a second on the carb cleaner if the ignition is firing. Take one of the plug wires off and make sure it will throw a good spark to ground, then you know youre getting spark. I have also heard of people getting one with a dead FI computer to crank by hot wiring the cold start injector, but that's dangerous if you don't watch out. Anyway, good luck getting it running, hopefully more people chime in soon Scott Edited May 15, 2013 by twofouroh Quote Link to comment Share on other sites More sharing options...
NewZed Posted May 16, 2013 Share Posted May 16, 2013 I do have the manuals for the car and have read the sections many times. But some questions I had just weren't answered there so here we go. -There is a vacuum hose leading from the distributor to a little cylinder with the other hose going to the carbon canister, is this needed of can I just plug off the hole. If it is needed, what do the two wires coming from the small cylinder plug into? The "small cylinder" is a solenoid that opens to let vacuum through to the distirbutor. The wires from the solenoid go to the top gear switch on the tranmsssion. It's described in the Emissions chapter. As twofouroh says, it shouldn't stop the engine from starting, you'll just never have vacuum advance if it does. One easy way to ballpark ignition timing is to put the timing mark on ~10 degrees, then look at where the rotor tooth (the six tooth iron rotor) is in relation to the pickup coil in the distributor. It should be about directly across from the exposed brass in the middle of the pickup coil. If it's not, turn the distributor until it is, then make sure that the distirbutor rotor is pointing at the #1 wire. Firing order is 1-5-3-6-2-4 in counterclockwise order. Cylinder 1 is at the front. While you're in there check the gap between the rotor tooth and the magnetic pickup coil. It's important, and adjustable, also described in the Engine Electrical chapter. Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 16, 2013 Share Posted May 16, 2013 Have you done everything as NewZed suggested in your previous thread ? Do you have any pic of your engine compartment or progress ? I know that you just the engine to start but with fuel injection you need to put everything together first before you start diag. it . Quote Link to comment Share on other sites More sharing options...
IncompetentOne Posted May 16, 2013 Author Share Posted May 16, 2013 (edited) fuel pump works filters are letting gas through fine but I will get a pressure gauge new gas, tank was drained and cleaned gas sprays out at high pressure when disconnecting the fuel rail Will look into the electrical connecters and I had a few minutes to spare so I went out and got someone to try to crank the car while I had my hand firm again the spark plug hole and it did not put any pressure on my hand at all so I assume it is compression! I took a quick glance at the rocker arms ant they are as stiff as a rock, so I will reset the valve lash on all cylinders when i buy the tools tomorrow. The front end of the car is up on jacks, so when I sprayed in starting fluid it all ran to cylinders 5 + 6. they ignited just fine. I will attempt to get some clear pics of everything the next time its light out. Thanks for the posts guys! Edited May 16, 2013 by IncompetentOne Quote Link to comment Share on other sites More sharing options...
pet280 Posted May 16, 2013 Share Posted May 16, 2013 You should get a compression gauge and do a test. The gauges are cheep from Harbor Freight. May not be the most accurate, but will give you a good idea on the compression of the motor. try to get some one else to crank the car while you spray the carb, or break clean in. You may want to look in to some node lights to verify if you have injector pulse. Quote Link to comment Share on other sites More sharing options...
IncompetentOne Posted May 16, 2013 Author Share Posted May 16, 2013 thanks! Quote Link to comment Share on other sites More sharing options...
twofouroh Posted May 17, 2013 Share Posted May 17, 2013 Brake cleaner is NOT carb cleaner or starter fluid!!!! It is basically dry cleaning fluid (non-flammable), and if you get it really hot, it can decompose into phosgene gas, which is deadly. I don't ever buy it for that reason. Welders tell horror stories about cleaning metal with it, then welding causes a trapped pocket of it to explode in their face as phosgene! Please read this guy's first hand account of what it did to him -----> http://www.brewracingframes.com/id75.htm Quote Link to comment Share on other sites More sharing options...
NewZed Posted May 17, 2013 Share Posted May 17, 2013 (edited) Excellent point twofouroh. Some of the new "green" brake cleaning products are hydrocarbon based, and will burn just fine, but the old halogenated ones, that produce phosgene, are still available. If I was trying to start an engine I would seriously consider using starting fluid. Edit - the halogenated Brakleen wouldn't burn by itself anyway so woudln't help start the engine. Edited May 17, 2013 by NewZed Quote Link to comment Share on other sites More sharing options...
twofouroh Posted May 17, 2013 Share Posted May 17, 2013 (edited) Why buy 'green' brake cleaner when it is flammable? Carb cleaner works better on brakes, IMO. I think the only point of old brake cleaner was to not explode every time a mechanic lit up while using it. I'd rather just stick with my core group than have a can of everything under the sun, I'd never have the right one when I needed it. . . . . . My cleaners: Alcohol 90%+ - the 70% stuff just leaves water behind Windex 409 Dawn dishwash soap, gets grease out of your way! Diesel - GREAT solvent, especially if you let it soak. Try soaking a piston top with it overnight, and then hit it with some light steel wool. Good on frozen bolts too. Carb cleaner - all around good for lots of stuff. Also used instead of starting fluid, brake cleaner, and wasp killer . Charcoal lighter fluid - this is a good substitute for gasoline - it works about the same and it is much harder to light, much less explosive. Less headaches too. The one thing I like the old style brake cleaner for is that it 'may' dissolve some things the others won't, like hard chewing gum, trim glue, or that butyl rubber crap. I never use it to prep metal, or clean brakes Edited May 17, 2013 by twofouroh Quote Link to comment Share on other sites More sharing options...
9rider Posted May 17, 2013 Share Posted May 17, 2013 Don't spray carb and crank the same time. I got a back fire almost burn out my eyebrows .Spray for 2 3 seconds most then crank your car. Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 17, 2013 Share Posted May 17, 2013 Don't spray carb and crank the same time. I got a back fire almost burn out my eyebrows .Spray for 2 3 seconds most then crank your car. You can , just don't pump your gas pedal . LOL . Quote Link to comment Share on other sites More sharing options...
pet280 Posted May 17, 2013 Share Posted May 17, 2013 The reason why is used at times instead of carb, or starter fluid, is cost. Plain and simple brake clean is a dollar, and on the bottom of the can says, 'DANGER: extremely flammable.' I can't think of one that I have used that wasn't. Although I do not doubt that it use to be that way. Learn something new everyday. Never used it to cool metal. Mainly because the stuff my shop uses is flammable. Any luck so far with getting the car started, or the problem narrowed down? Quote Link to comment Share on other sites More sharing options...
motomanmike Posted May 17, 2013 Share Posted May 17, 2013 Buy a NOID light at autozone or somewhere. The sets are like 20-30 bucks. They are just a small light to plug on the injector leads to see if they are firing. Sounds like the injectors aren't firing. Quote Link to comment Share on other sites More sharing options...
IncompetentOne Posted May 18, 2013 Author Share Posted May 18, 2013 Buy a NOID light at autozone or somewhere. The sets are like 20-30 bucks. They are just a small light to plug on the injector leads to see if they are firing. Sounds like the injectors aren't firing. Thats my guess, the spark plugs dont even smell like fuel. Could the lash gap have anything to do with that? There was no compression in the cylinders because both the valves were always open. but shouldn't the injectors still shoot fuel into the cylinders? I will get a noid light thing and start testing Quote Link to comment Share on other sites More sharing options...
Tony D Posted May 18, 2013 Share Posted May 18, 2013 (edited) Kindler, gentler group here these days. Afraid of Phosgene. Hell, I bet you don't mix Clorox and Vanish to get a whiter cleaner toilet bowl either! You want a real cleaner? Methylene Chloride, 1,1,1 Trichlorethane, Carbon Tetrachloride... MEN'S CLEANERS... Weeds out the weak early in the apprenticeship period... As for valves....we got an engine in once where the builder turned the lash adjusters up all the way and cranked the engine. Oops, bent and valves and broken guides...no compression nor vacuum. Check your lash to get correct vacuum signal to FPR. Injectors fire (NOID Light) every third ignition pulse. You can test it by scratching the negative off the coil "key on" agains ground quickly. Scratch, Scratch, Scratch "CLICK" next scratch could give you a boom out the intake or exhaust as the injected gas in whatever cylinder is pointed to on the distributor cap lights off with continued sparking in the cylinder... But it lets you do a fender check quickly to verify it is all working. Then it's a matter of degrees. If it runs on sprayed ether (starting fluid) the ignition is OK and it's fuel (volume, likely) getting to the cylinders. EFI Bible is critical to have at hand during this testing phase to component check properly. Edited May 18, 2013 by Tony D Quote Link to comment Share on other sites More sharing options...
IncompetentOne Posted May 18, 2013 Author Share Posted May 18, 2013 good lord there so much that I dont know about cars... I will fiddle with it in the morning to see if i can get a pulse going. Also: i held ope the AFM flap with a screwdriver and tried to start the car, two of the cylinders (5 +6) fired but none of the others. I believe the lash on these two are fine which makes sense. Does that sound reasonable? Quote Link to comment Share on other sites More sharing options...
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