Guest Carrman Posted October 10, 2003 Share Posted October 10, 2003 Hey folks, got a bit of a problem here. My '75 with L28ET is becoming a pain to get started in the morning. I originally thought I had injectors leaking down, so I replaced all of them with a set of new Standard brand injectors with the revised tips on them. When I pulled the rail, three of the old injectors had wet tips on them, so I figured they were leaky. Unfortunately, the problem did not leave. After sitting overnight, when I go to start up in the morning, I have to crank on it for about 5 to 10 seconds. When it decides to finally light off, it stumbles and barely runs for a few seconds, then finally begins to idle. At this time, there is the overpowering gas smell present, like leaking fuel. The second part of the problem, which may or may not be related, is that the spark plug on #4 would foul and not fire for the first minute or so, then it will clear up and fire correctly. When I pulled the plug, the insulator is a dark brown, and the plug smells like burnt electrical components. I brush it off, and reinstall it, and it's fine for a few days, then it misses at start again. I have now swapped that plug with another to see if the miss returns to that cylinder, or if it follows the plug. The funny thing with all of this, if the car only sits for an hour or so, it immediately starts when I hit the key. No plug fouling, no smell. All fuel hoses are new, I've looked high and low for fuel leaks. Anyone have any ideas? Dave Quote Link to comment Share on other sites More sharing options...
David K Posted October 10, 2003 Share Posted October 10, 2003 Fuel pump not holding pressure in the lines? Sounds like you let it sit overnight, and the fuel drains back into the tank in reverse. That would make sense if you have to crank it for a few times before you get anything, and it runs rough for a while. Just a thought. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted October 10, 2003 Share Posted October 10, 2003 Just to add what David said... it could also be a fuel pressure regulator leaking down...allowing fuel pressure to be lost... Quote Link to comment Share on other sites More sharing options...
Guest Carrman Posted October 10, 2003 Share Posted October 10, 2003 You guys are probably on the right track, but why the gas stench? That's one thing I can't think of a reason why. Can the regualtor fail in such a way that gas can be drawn through the vacuum line that operates it? Dave Quote Link to comment Share on other sites More sharing options...
fl327 Posted October 11, 2003 Share Posted October 11, 2003 Hey carrman, we have the same car!!!! I have a 75 turbo as well. My car does the same thing!!!! Its not the regulator, or the injectors. Every morning I do this to start my car, turn the key on to ACC, and let the fuel pump run for a 10 count like 1 one thousand, 2 one thousand, 3 one thousand...blah. Then I only crank the car two seconds at a time, it usually starts 1st try, sometimes it takes more. It starts easier if I pump the pedal a little bit when I do it too. Mine idles like crap for the first minute, until the system gets to charge a little bit, then it steadies out----I have no idle control or emissions, and it always idles a little rough, especially on cold mornings, and a little rich---I believe its the Head Temp Sensor running you a little rich on that end, since mine doesnt have the air regulator or cold idle system whatever its called-ecu cant raise idle for me, but it will still throw out the extra fuel--if you hold rpm up to 900 or so it will be fine- it leans it out a bit, At least from my experience. If you do have the idle stuff on your manifold, I would check to see if its working right. How do you have your fuel pump wired? Are you running the stock modulator or the hotwire method? Before I get to driving and the alternator kicks on, it runs a little rough since the alternator hasnt reached its excite rpm. Once I do excite the alt-idle gets even smoother. I wouldnt worry so much, unless this is a new issue that has come up out of the blue. Mine does this and I have a very healthy functioning fpr, maybe I will switch it out and see if that makes a difference, but I dont think it will. Quote Link to comment Share on other sites More sharing options...
Guest Carrman Posted October 11, 2003 Share Posted October 11, 2003 327, this is a new problem unfortunately. Used to start pretty easy in the mornings. Dave Quote Link to comment Share on other sites More sharing options...
Drax240z Posted October 11, 2003 Share Posted October 11, 2003 I have the exact same issue, though not with the stock EFI system. I basically let the pump run for about 6 seconds before starting, and then it will start, but sortof roughly. It takes 15 seconds or so before it actually runs right. I'm just now thinking that this may be related to the miss I get a light throttle cruising... Everyone changed their plug wires lately? Quote Link to comment Share on other sites More sharing options...
Guest Carrman Posted October 12, 2003 Share Posted October 12, 2003 Well, I solved a lot of my problem today. I grabbed the fuel line to the fuel rail, and was able to pinch it shut with my fingers. This told me there was no pressure in the system after sitting all night. I cycled the key 6 times to get the fuel pump to run and reprime the system. After doing this, I began to look at ALL fuel lines under the hood. I began to smell gas at the front of the car, so I looked closely and found a wet fuel line at the bottom of the fuel filter. Bingo! Turns out the flippin' clamp came loose......... Doh!!!!! I still am waiting to see if the engine miss returns though. I'll let you all know if it does. Thanks for the replies I got, this is truly the most technically informative Z forum in existence. Dave Quote Link to comment Share on other sites More sharing options...
VinhZXT Posted October 20, 2003 Share Posted October 20, 2003 Hey all, I have something for u guys. I just bought an 81 280ZXT from a junk yard for a new young Z enthusiast and it has 64K miles on it. It went thru many shops and they could get it to start and that's how it ended up in the junkyard. Anyway I towed it home and begin to check for fire, fuel and even did a compression check. Everything turn out good but still no start. I remove the air filter and stick a screw driver into the AFM and it starts up OK but idle rough. I let it warm up a bit and shut it off and restart it again and it starts fine. So I let it cool down and the next morning I tried again and no start. Put my new AFM from my running 280ZXT in and still no start ??? WTF is going on? I open up the AFM and release the tension on the flap and the car started. let it warm up a little and it gave good throttle response.. shut it off and try it again the next morning and it started up fine.. Still need to warm up before it gives good throttle response. As a conclusion I think you should check the AFM. good luck Quote Link to comment Share on other sites More sharing options...
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