robftw Posted June 6, 2011 Share #1 Posted June 6, 2011 (edited) Its got a really rough idle.. moving the dizzy does not do Anything to improve it. around 300-700 rpmOddly, if i press down on my dizzy cap the idle speeds up quite a bit and sounds decent.. maybe i should replace the cap too? I nudged one of my injector clips on accident and it came off, it did not change the idle at all, i think my injectors might be bad, or my dropping resistor... which sucks. I'll have a video up in a few minutes.edit: video http://www.youtube.com/watch?v=5n5Vv4dVxI8 Edited June 6, 2011 by robftw Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/ Share on other sites More sharing options...
SteveJ Posted June 7, 2011 Share #2 Posted June 7, 2011 Check the connections of the wires on the cap and check the condition of the contacts in the cap and the rotor. For the latter two, you're interested in carbon build-up or wear.Did you ever check your fuel pressure?You could have multiple problems combining. Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-357994 Share on other sites More sharing options...
FastWoman Posted June 7, 2011 Share #3 Posted June 7, 2011 If your maintenance ignition components are old, just replace them. It's not expensive. You need:NGK B6ES-11 plugs (pretty sure that's the right one)NGK blue spiral-wound plug wirescaprotorAlso inspect your distributor. Does the shaft wobble? Does the breaker plate (what you're looking at when you remove the cap and rotor) turn freely and without binding. If your distributor is bad, you can (sometimes/usually) buy a rebuilt one from your local auto parts store for around $100. Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358040 Share on other sites More sharing options...
robftw Posted June 7, 2011 Author Share #4 Posted June 7, 2011 Here is some more detailsFuel pressure is good, 35-40 psi at idle The plugs are brand new NGK Part # 3824 {#BR6ES11} Standard .44 gapThe distributor is Brand new, i set the engine to TDC, marked the #1 position on the old distributor and matched the new one to its old location The cap points are worn - im installing a new one todayThe rotor is also kind of corroded (i used emery cloth to clean it off) but im installing a new one today. Plug wires are brand new, they have been checked for good contact with the plugs / capNow here are some symptoms.. When i push down on the cap itself the idle speeds up and sounds normal.When i mess with the plugs nothing changesWhen i move the dizzy nothing happens I do not have any vacuum leaksI pulled an injector plug and it did not change the idle speed, so its not running on all cylinders, but when i push down on the cap and pull the injector plug its audible that something is missing. I hope its just a bad cap Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358042 Share on other sites More sharing options...
Zed Head Posted June 7, 2011 Share #5 Posted June 7, 2011 Check the vacuum hose from the intake manifold to your fuel pressure regulator. Fuel pressure should be ~30 psi or lower at idle, depending on intake vacuum. You'll run a little rich and gassy without it connected. Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358045 Share on other sites More sharing options...
71Nissan240Z Posted June 7, 2011 Share #6 Posted June 7, 2011 You replaced everything except the caP? replace the cap! Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358051 Share on other sites More sharing options...
SteveJ Posted June 7, 2011 Share #7 Posted June 7, 2011 Back in 2008 I was checking out a 74 for sale that wouldn't run. I messed around with it a little bit and eventually found that the current from the coil erroded the plastic on the cap where the coil wires attaches. I got a new cap and new plugs and got the car running. I bought the car, too. Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358059 Share on other sites More sharing options...
grantf Posted June 7, 2011 Share #8 Posted June 7, 2011 Sounds like something is wrong with the center contact from the coil on the cap no? Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358070 Share on other sites More sharing options...
FastWoman Posted June 7, 2011 Share #9 Posted June 7, 2011 Sounds like something is wrong with the center contact from the coil on the cap no?That's what I'm thinking too, which was why I suggested replacing ignition components.Sometimes the center contact between the cap and the rotor can be bad. For instance there might not be physical contact between the two. Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358073 Share on other sites More sharing options...
robftw Posted June 8, 2011 Author Share #10 Posted June 8, 2011 (edited) I got the cap and rotor on and it fired right up, it ran great for a while and then developed the same symptoms again, however my friend came by (who happens to be a master nissan tech..) And after a few wire traces we found a few injectors to be clogged, so i'll be getting some fuel treatment tomorrow and having at it. I drove it home with no headlights with said friend following me, Open headers as well... All i can say is it was scary / awesome at the same time. I've never had so many people clap and shout at me in a vehicle before.. all the beach goers were loving it. We traced the headlight wire too, the redstripe white wire is the culprit. Another thing i figured out is that my right turn signal is not turning on either.. Lastly, i have the dreaded clutch slave/master length problem.. i checked everything to make sure they matched up and the clutch refused to disengage completely.. i ended up building a spacer on the lathe to bandaid it for now, it feels like the clutch is slipping a little bit, i need to shorten it. 1 bad bulb in the speedo, and the clock. Edited June 8, 2011 by robftw Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358097 Share on other sites More sharing options...
SteveJ Posted June 8, 2011 Share #11 Posted June 8, 2011 Read up on relays for the headlights. Between myself and Dave Irwin, you can find lots of information on the headlight circuit.As for the turn signal, check to see if it lights up with the hazard switch. That will give you some idea of where the problem is. Just follow the wiring diagrams in the FSM. Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358100 Share on other sites More sharing options...
robftw Posted June 8, 2011 Author Share #12 Posted June 8, 2011 (edited) It doesn't with the hazard switch eitherIt won't click in place either..(with the turn signal switch) i think it might be something in the column Edited June 8, 2011 by robftw Link to comment https://www.classiczcars.com/topic/39817-it-runs-bad/#findComment-358102 Share on other sites More sharing options...
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