dj paul Posted April 29, 2007 Share Posted April 29, 2007 Alright guys i gotta new stupid problem with my 80' 280ZX. I put optical ignition in it because im eventually going to go with the 300zx MAF/ECU. I noticed that it was real sluggish at low rpms but acted normal above high rpms. Also it had a goofy starting issue, it would always start, but not like it normally does (took a few more cranks) Since i wasn't doing the 300zx MAF/ECU swap for a little while i just decided to put the stock ignition back in. It started up and i drove it around the neighborhood. Still felt a little sluggish so when i got back home i shut it off and then tried turning it back on to see if it would start, because i was just going to leave it alone since i had to go to work later. No start. I took out #1 spark plug and cranked it, its getting spark. I can also smell gas when i try and start and gets a good 30psi right before fuel rail, but it doesnt seem like it even wants to fire on any cylinders. just cranks and cranks. Im almost fed up with this thing and just wondering any ideas or simple tests to run to help me out? Quote Link to comment Share on other sites More sharing options...
Mr.INSANE Posted April 29, 2007 Share Posted April 29, 2007 Weak Spark, Incorrect Timing, Timing belt slipped a tooth Etc Etc Just some ideas to look at first! Quote Link to comment Share on other sites More sharing options...
dj paul Posted April 29, 2007 Author Share Posted April 29, 2007 alright ive been thinking and how realistic is it for the timing chain to slip a tooth? when putting in the optical ignition you have to put it at stock ignition timing which is of course is 10 BDC. So i put a jumper wire on the starter since i didnt have a socket big enough to turn crank. There was a point where i tried turning it just a little by hand and it seemed to move and then did not move any more by hand. does that sound like that could have jumped a tooth? I mean, i put my hand on the balancer and just tried turning it and it moved just like 2 deg clockwise then didnt move anymore. Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted April 30, 2007 Share Posted April 30, 2007 I think you have things confused (you have me confused with what you say anyway). If you understand all of what I'm about to say then I apologize for explaining what you already know and you could just skip down to the question at the end: You set ignition timing with a timing light. It has nothing to do with where you left the engine before you put the distributor on. I'm assuming you're taking the distributor off because I don't know exactly what a 300zx optical ignition consists of. Anyway, what you need to do is get the engine to TDC. It helps if you take the spark plugs out because the compression in the cylinders makes the engine want to stop at different positions other than where you want it to. So you've got the engine set at TDC (your thumb is getting pushed off of the #1 cylinder so you're on the compression stroke and your timing mark on the pulley is at the "0" on your timing indicator). You take off the cap on the distributor and your rotor should be pointing directly at your #1 post on the cap. If it's pointing in the opposite way then you're 180 out and you should unbolt the distributor and turn the rotor towards #1 and make sure it seats before you bolt it down. Then you make sure all of your wires are on the right plugs/posts COUNTERCLOCKWISE on the cap. You should be able to start the car with the timing anywhere in the inch or so of the slot on the distributor. If you set it right as described and the car didn't start then you must be having other problems. If it starts then set the timing with a light WITH THE COMPUTER ADVANCE DISCONNECTED if you have it (not sure about 1980 but it will be a connector on the SIDE of the ignition module on the distributor) and you should be good to go if not atleast you know this part is right. Why did you go ahead and change the ignition to begin with? Were you having problems before or just looking to jumpstart your 300ZX ecu swap? Quote Link to comment Share on other sites More sharing options...
dj paul Posted April 30, 2007 Author Share Posted April 30, 2007 looking to jumpstart my 300ZX ecu swap. i need to just get it running and leave it alone untill i get my other Z going. all i have left to do is weld up the front mounts of the rear suspension (putting S13 subframe on 240Z) and mock up the SR20DET and it will be done. Anyways, the way i set motor to 10 BDC was i would jumpstart the starter untill the rotor got around the #1 plug and the notch hit 10. This is what the manual for the Optical ignition said to do. hooked up new ignition, put optical sensor on the leading edge of the shutter and hooked up coil. started right up. when i drove it it was sluggish though. Its automatic so when u floor it it always downshifts a gear you know? but after, when u would floor it it would just keep accellerating, no gear change, and slower than normal. #1 the no downshifting could just be a coincidence and #2 i hate automatics. Any other ideas though? im going to put motor at 0 TDC tomorrow and take valve cover off and see if the marks are lined up on the cam gear. Also im going to try my other stock ignition module(first). Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted April 30, 2007 Share Posted April 30, 2007 I would think with the transmission you have either disconnected or broken the kickdown cable (if these things even have one) or the vacuum line (which would cause the car to run poorly at low rpms). Ignition modules on these things are good at going out too. Quote Link to comment Share on other sites More sharing options...
dj paul Posted April 30, 2007 Author Share Posted April 30, 2007 alright, i got the motor set at 0 deg and the rotor is pointing the completely opposite way of #1. the only thing was, the other day it was not like this. could that mean my chain is off by a tooth? anyways, should i just unbolt dizzy and move rotor to #1 like you were saying? Quote Link to comment Share on other sites More sharing options...
dj paul Posted April 30, 2007 Author Share Posted April 30, 2007 This morning the car started up just fine, i let it run till it got to operating temperature and then turned it off. waited a few minutes and tried to start again, it just cranks and cranks. I re-oriented the distributor in the right way and made sure it seated and then locked it down. this did not help, i put on the other ignition module i had, nothing. Since it doesnt start when its hot im beginning to think its some sort of vacuum leak that manifests itself when hot??? im running out of ideas. I almost forgot, I set to 0 deg and took valve cover off, timing link on chain is set to 1 on sprocket which is correct. Edit: should i try another ECU? maybe i fried mine when changing ignition? should i try another AFM? i can get these from my friend for free. Quote Link to comment Share on other sites More sharing options...
dj paul Posted April 30, 2007 Author Share Posted April 30, 2007 Nevermind. Screw the stock system!!! i already got it running on the 300ZX MAF/ECU. I went into one of my mad rages where i become superproductive. lol. Just have a few kinks to work out. Going to discuss it over in electrical... Quote Link to comment Share on other sites More sharing options...
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