JeepJoe Posted January 22, 2020 Share Posted January 22, 2020 I am trying to start my 1990 MJ but have no spark. THis truck hasn't been started for over a year due to needing a clutch job. All the spark plug wires had bad corrosion, also the ignition coil connection points were corroded, I have cleaned all of these. I'm using an in line spark tester and I'm getting no spark however the motor cranks over fine. Any ideas what I need to check next? Also any good ideas on how to clean the electrical connectors I'm pointing to on the ignition coil? I tried my best but the copper is still not shiny. 1990 MJ 4.0, AX15, 4x4, longbed pioneer Link to comment Share on other sites More sharing options...
87MJTIM Posted January 22, 2020 Share Posted January 22, 2020 I'm going to sound like a broken record, but... Perform Cruiser's Renix Tips first before shooting parts at it. Especially test the CPS. If it is not functioning the ECU will not send power to the ignition system. Link to comment Share on other sites More sharing options...
Warren Mohler Posted January 22, 2020 Share Posted January 22, 2020 CPS#1 Link to comment Share on other sites More sharing options...
Ωhm Posted January 22, 2020 Share Posted January 22, 2020 Manuals have been known to get clutch stuff stuck to the tip of the CPS. There's a magnet there. Test for voltage (AC) first. Link to comment Share on other sites More sharing options...
JeepJoe Posted January 22, 2020 Author Share Posted January 22, 2020 Yep I'll start working my way through Cruisers tips, just wondering which numbers are most connected to no spark issues. 1 hour ago, 87MJTIM said: I'm going to sound like a broken record, but... Perform Cruiser's Renix Tips first before shooting parts at it. Especially test the CPS. If it is not functioning the ECU will not send power to the ignition system. Link to comment Share on other sites More sharing options...
JeepJoe Posted January 22, 2020 Author Share Posted January 22, 2020 22 minutes ago, Warren Mohler said: CPS#1 Where is CPS #1? Link to comment Share on other sites More sharing options...
yxmj Posted January 22, 2020 Share Posted January 22, 2020 He means his first guess is the crank position sensor Link to comment Share on other sites More sharing options...
Warren Mohler Posted January 22, 2020 Share Posted January 22, 2020 Link to comment Share on other sites More sharing options...
87MJTIM Posted January 22, 2020 Share Posted January 22, 2020 3 hours ago, JeepJoe said: Yep I'll start working my way through Cruisers tips, just wondering which numbers are most connected to no spark issues. 1, 2 ,4, 5 & 7. The rest are good to perform, but these directly effect electrical signals. (not that other ones don't effect electrical signals) Link to comment Share on other sites More sharing options...
Jeep Driver Posted January 23, 2020 Share Posted January 23, 2020 8 hours ago, JeepJoe said: THis truck hasn't been started for over a year due to needing a clutch job. Did you or anyone install a new clutch? Link to comment Share on other sites More sharing options...
SVPete Posted January 23, 2020 Share Posted January 23, 2020 Nice shirt Link to comment Share on other sites More sharing options...
JeepJoe Posted January 23, 2020 Author Share Posted January 23, 2020 2 hours ago, Jeep Driver said: Did you or anyone install a new clutch? Not yet, that's why it's been sitting Link to comment Share on other sites More sharing options...
JeepJoe Posted January 23, 2020 Author Share Posted January 23, 2020 Good news guys. Checked the cps, and the dumb thing wasn't installed! I guess the guy I bought it from took it off when he started the clutch replacement. Mutch swearing and an hour later had it back in, Cruiser thanks for the tape and 11mm socket idea. So now it cranks, and I have spark all the way to the cylinders, but it still won't start. When I use starter fluid I get some back fireing, but the motor won't even cough or sputter. At least I'm a step forward! Any new ideas?? Link to comment Share on other sites More sharing options...
JeepJoe Posted January 23, 2020 Author Share Posted January 23, 2020 28 minutes ago, SVPete said: Nice shirt Thanks Link to comment Share on other sites More sharing options...
yxmj Posted January 23, 2020 Share Posted January 23, 2020 If it has been sitting I would drain the gas and put in known good fresh fuel....? Link to comment Share on other sites More sharing options...
cruiser54 Posted January 24, 2020 Share Posted January 24, 2020 Tips 1 through 5, in that order for your issue. Link to comment Share on other sites More sharing options...
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