SoFlaZ06 Posted October 10, 2017 Author Share Posted October 10, 2017 7 minutes ago, NewZed said: I would focus on the quality of the signal on the blue wire to Pin #1 at the ECU. I have solved tachometer problems by adding a condenser to the negative terminal circuit. The signal was noisy. and the condenser cleaned it up. Hook up your noid light to the coil negative terminal and see if it behaves normally or shows some weirdness. thanks for the tips, I'll give the tach a shot. and as you mentioned that, I did connect the noid light directly to the coil, and it flashes during cranking. Quote Link to comment Share on other sites More sharing options...
spiff Posted October 17, 2017 Share Posted October 17, 2017 does it flash when you connect it at the ecu? Quote Link to comment Share on other sites More sharing options...
Marks260z Posted October 24, 2017 Share Posted October 24, 2017 Long shot for you. You mentioned it was out of a ZX? I had a ZX that had the same random symptoms and I traced it to the oil pressure sensor that was on the way out. The ZX added a fail safe to shut down the injectors in case of no oil pressure to save the engine. The stock oil pressure sensor fail fairy often. After checking ALL grounds after that I would try swapping the ignition sensor from the side of the dizzy and see what you get since you have access to a running match car. Good luck! Quote Link to comment Share on other sites More sharing options...
D9inger Posted January 7, 2018 Share Posted January 7, 2018 Did you ever figure out what was going on? My 78 did this to me yesterday. Quote Link to comment Share on other sites More sharing options...
NewZed Posted January 7, 2018 Share Posted January 7, 2018 On 8/28/2017 at 6:32 PM, SoFlaZ06 said: So i'm driving one day, and car just dies. It will turn the engine over, but won't start. It did this? Quote Link to comment Share on other sites More sharing options...
D9inger Posted January 7, 2018 Share Posted January 7, 2018 yes, was pulling in the driveway and it died, like I turned off the ignition with the key. Now it will crank but no accessory lighting, seat belt warning, or anything that is normally on with the key selected on. Strangely enough if I turn the key to start it will crank but it will not start, BUT if I turn the key slightly back toward off I get the accessory stuff, seat belt warning, etc. I'm thinking its a ignition (key) switch.....? If it'll ever warm up I'll dig in and troubleshoot. Quote Link to comment Share on other sites More sharing options...
NewZed Posted January 7, 2018 Share Posted January 7, 2018 Do the basics with a meter. Turn the key on and check for power at the coil and at the injectors. Check for coil power when you turn the key to Start. Check your fuses and fusible links and grounds. Could be a simple loose connection or something like a bad ignition relay. Once you know what's getting power when it should and what's not you'll have a clearer idea of what might be wrong. Quote Link to comment Share on other sites More sharing options...
D9inger Posted January 7, 2018 Share Posted January 7, 2018 Will do and report. Thank You, Warmer weather coming this next week. Dave Quote Link to comment Share on other sites More sharing options...
D9inger Posted January 13, 2018 Share Posted January 13, 2018 (edited) turns out it was the relay, unmounted it and with it plugged up still and a ground added to the mount bracket I noticed it was intermittent. So I did a quick search and discovered they are not available anywhere. Figuring I had nothing to loose I straightened the tabs and removed the cover and found the ground strap was broken. I tried adding a ground by drilling a small hole in between the relays and soldering the coil grounds to it but I think I had tired 40 year old relays in addition to the broken ground strap. I got to looking for solutions and found this along with information of people offering relay harness adapters for sale and links to the 6 pin non locking connector. The ready made ones were $75-80 delivered, the 6 pin connector was $3 and another $35 for the crimper I was getting ready to cut the OEM connector off and splice in a set of relays and decided to see if I could get the relay contacts to release from the OEM connector. A dental pick and some patience and I was able to get them to release and they are exactly the same size as the ones in the new relay sockets. So one at a time I removed and reinstalled the OEM wires and connectors into the new relays sockets, checked everything with my meter, added a terminal end to the black grounds and plugged in the relays. Works, not expensive and with the exception of the relay sockets, no new connections to fail. As an added bonus the holes line up with the originals so remounting was a breeze. Edited January 13, 2018 by D9inger added pictures Quote Link to comment Share on other sites More sharing options...
NewZed Posted January 13, 2018 Share Posted January 13, 2018 That is some nice detective work, and solution. Do you have the info on the replacement relay? They don't last forever, I have a dead one sitting in front of me right now. Luckily, my car came with a spare. Quote Link to comment Share on other sites More sharing options...
D9inger Posted January 13, 2018 Share Posted January 13, 2018 (edited) Thank You, I did discover the 1978 FSM schematic was incorrect too. It won't work like they drew it and the wiring in the car confirmed it. The giveaway was the top left pin on the drawing had 2 wires in it and nothing in the bottom left. There was one wire in each on my car. The one on the left is original, the one on the right is corrected. I used standard Bosch relays, I bought a 10 pack off ebay. I had to do the headlight mod earlier and figured I'd need them. http://forums.hybridz.org/topic/127971-led-headlight-bulbs-anyone-tried-them/?tab=comments#comment-1196144 Dave Edited January 13, 2018 by D9inger . Quote Link to comment Share on other sites More sharing options...
NewZed Posted January 13, 2018 Share Posted January 13, 2018 Could be worse. Here's the one that came out of my car, a 1976 model. The one in front of me now is actually my EFI relay, I was mixed up on my last post. Thanks for the tip on the wiring diagram. Quote Link to comment Share on other sites More sharing options...
D9inger Posted January 13, 2018 Share Posted January 13, 2018 Wow... Did that get wet or something? Quote Link to comment Share on other sites More sharing options...
NewZed Posted January 13, 2018 Share Posted January 13, 2018 That area is where the water drains down if it gets through the windshield, and the car is angled a certain way. The car has water marks under the passenger seat from the puddle that sat there for while. Only the Accessory relay didn't work though. The PO had a jumper wire ran up to the ignition switch for that. Quote Link to comment Share on other sites More sharing options...
Milligan21 Posted March 10, 2023 Share Posted March 10, 2023 On 10/10/2017 at 8:43 PM, NewZed said: resistor in the line to the tachometer Hey... Maybe you can tell me or show me in a picture where this POXY resistor is. I been over everything now in my car and this is what I cant find to check Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 11, 2023 Share Posted March 11, 2023 I assume that you mean the inline resistor on the line from the ignition coil to the tachometer. I don't know what "POXY resistor" means. It's in the wiring harness by the fuse panel under the glovebox. You can see the lump under the tape. It is rarely a problem. Shouldn't affect starting. Quote Link to comment Share on other sites More sharing options...
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