Brendan280z Posted May 29, 2013 Share Posted May 29, 2013 Hey all, long time reader and lurker here on the HybridZ forums. Always had a dream to buy and build a S30 series. Finally bought one. 1977 EFI 280z. When I got it it wasn't running, messed around with the ignition system and sure enough the PO had the firing order backwards, then fixed the fuel problem (new lines / fuel pump). Now here is the dilemma, it idles fine and has correct fuel pressure. However, it doesn't want to rev up. The tachometer is either unhooked or broken I am not sure. So I cannot tell you when it cuts out exactly. I have the FSM and EFI Bible! Thanks guys look forward to getting to know all of you.-Brendan Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted May 29, 2013 Share Posted May 29, 2013 Have you done basic maintenance or do you know if all the basics have been replaced? Dizzy cap,rotor, belt, oil change, rad fluid? are the grounds and connectors nice and clean? Have you checked the fuel pressure at the rail? that could cause it to cut out as well. Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 29, 2013 Share Posted May 29, 2013 Check your AFM flap movement when you increase the throttle . Good looking car , was it red before ? Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 29, 2013 Author Share Posted May 29, 2013 Will do later tonight when I get off of work, It was red, I have no idea why they painted it orange (house paint at that) After I get it running the plan is to go white with it. It was a steal at $200 Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 29, 2013 Author Share Posted May 29, 2013 (edited) Have you done basic maintenance or do you know if all the basics have been replaced? Dizzy cap,rotor, belt, oil change, rad fluid? are the grounds and connectors nice and clean? Have you checked the fuel pressure at the rail? that could cause it to cut out as well. Distributor cap, plugs and wires, oil + filter, radiator flush, gas tank flushed cleaned and sealed, Haven't checked the grounds nor connectors I will have a go at that tonight. Fuel pressure at the rail (right before it after the filter) is around 34 psi. Edited May 29, 2013 by Brendan280z Quote Link to comment Share on other sites More sharing options...
9rider Posted May 29, 2013 Share Posted May 29, 2013 You may want to check the TPS if it is working. You can open it up and see if you accelerate , the flap should leave the idle contacting point and touch the accelerate flap. If it doesn't touch, try use to screw driver to make contacting point and twist the throttle to see if it still stumble. My Z has same issue until I found out the TPS never touch the WOT position. Quote Link to comment Share on other sites More sharing options...
NewZed Posted May 29, 2013 Share Posted May 29, 2013 However, it doesn't want to rev up. Too wordy. Try to simplify. Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 29, 2013 Author Share Posted May 29, 2013 Too wordy. Try to simplify. When the car is cold it will rev up strong but it seems to hit a "wall" When the car starts to warm up it will not stay running. Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 29, 2013 Author Share Posted May 29, 2013 You may want to check the TPS if it is working. You can open it up and see if you accelerate , the flap should leave the idle contacting point and touch the accelerate flap. If it doesn't touch, try use to screw driver to make contacting point and twist the throttle to see if it still stumble. My Z has same issue until I found out the TPS never touch the WOT posi I will check this out when I get home and post the results and take some photos! Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 30, 2013 Author Share Posted May 30, 2013 Quick update, tps and afm are fine. I suspect it is the afm boot as it is cracked. Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 30, 2013 Share Posted May 30, 2013 Quick update, tps and afm are fine. I suspect it is the afm boot as it is cracked. That'll do it . Check all hoses down stream of AFM . Unmetered air equals incorrect fuel input . Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 30, 2013 Author Share Posted May 30, 2013 PO murdered the vacuum system. Bought all new vacuum line yesterday 6 feet of every size hope this is enough. And some black silicone to attempt to repair the afm boot. Thank you guys for all the help! ALSO. Is there an easy way to put the clutch pedal clevis pin back in???? Jeez or is it some sick initiation ritual? Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 30, 2013 Share Posted May 30, 2013 I would get a new boot , not that pricey . Not much room to work with under dash , get a small kid to do it for you . LOL . Quote Link to comment Share on other sites More sharing options...
ttodhunter Posted May 30, 2013 Share Posted May 30, 2013 I had a similar problem on my '76 which turned out to be the computer. It would idle fine, but if you touched the gas pedal, it would kill the engine. I did go through every test in the EFI Bible and was lucky enough to find a computer on Craigslist for $20 which fixed the problem. Note: There are different ECM's for different years that aren't interchangeable. Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 30, 2013 Author Share Posted May 30, 2013 I would get a new boot , not that pricey . Not much room to work with under dash , get a small kid to do it for you . LOL . LOL :^) Im 19 and its a pain! Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 30, 2013 Author Share Posted May 30, 2013 I had a similar problem on my '76 which turned out to be the computer. It would idle fine, but if you touched the gas pedal, it would kill the engine. I did go through every test in the EFI Bible and was lucky enough to find a computer on Craigslist for $20 which fixed the problem. Note: There are different ECM's for different years that aren't interchangeable. The ECM is good al the tests came back positive and the injectors ground out nicely. Thanks though!! Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 30, 2013 Author Share Posted May 30, 2013 I had a similar problem on my '76 which turned out to be the computer. It would idle fine, but if you touched the gas pedal, it would kill the engine. I did go through every test in the EFI Bible and was lucky enough to find a computer on Craigslist for $20 which fixed the problem. Note: There are different ECM's for different years that aren't interchangeable. The ECM is good al the tests came back positive and the injectors ground out nicely. Thanks though!! Quote Link to comment Share on other sites More sharing options...
noelawinslow Posted May 30, 2013 Share Posted May 30, 2013 LOL :^) Im 19 and its a pain! I had to ask the smallest girl I knew if she could reach up there and attach the vacuum line. Ten seconds before she arrived I managed to slip the line onto the water cock. Quote Link to comment Share on other sites More sharing options...
Leon Posted May 30, 2013 Share Posted May 30, 2013 (edited) ALSO. Is there an easy way to put the clutch pedal clevis pin back in???? Jeez or is it some sick initiation ritual? It's definitely the latter! I hate that clevis and cotter pin... I have to use long needle-nose pliers, no way in hell do my hands fit up there. Edited May 30, 2013 by Leon Quote Link to comment Share on other sites More sharing options...
Brendan280z Posted May 31, 2013 Author Share Posted May 31, 2013 I had to ask the smallest girl I knew if she could reach up there and attach the vacuum line. Ten seconds before she arrived I managed to slip the line onto the water cock. Called the girlfriend over! She got it done quick! (little hands!) Quote Link to comment Share on other sites More sharing options...
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