VSTwister
Well-Known Member
I've run into another brick wall.....
In trying to make adjustments to my carburetor, something else has come up so now I can't tune the carb because the engine won't run!
The package: 71 Scamp, stock 318, 904 trans, 4bbl Holley 1850 carb with Weiand Stealth intake, upgraded to Mopar electronic ignition years back (4 pin, single ballast, orange box), with accel wires, super coil, and plugs. All else stock replacement or original. Oh I did add a Sunpro tach recently.
Car was running fine for the most part, hard cold starts and some backfiring through the carb so yesterday I took the carb off to make some bench adjustments to the fast idle and secondary plates. Put carb back on, cranks but no firing up. A few times it did actually fire up, but it ran REALLY bad and just barely (at around 300-500rpm) and would stall. Getting fuel, check. Getting spark...sorta. On #1 wire, I was getting what seemed to be an intermittent spark fire. When it did, it was a good blue spark, just not consistent it seemed. Last week I did have some issues with getting no spark at all, but after finding the main coil wire was not connected tightly, that seemed to do the trick.
Today I was trying to troubleshoot the problem some more. It seemed now though I was getting a consistent good spark but still engine cranks and does that "almost ready to fire up but not quite" routines. But it won't even fire up the least bit now. Checked power to ballast resistor and resistor ohms...all comes out fine. Power is a little weak at 10.5 to 11 volts (but battery is weak from cranking too, it is at 12.1 volts right from the terminals) and ballast ohms are 1.4. Went to get some dinner, came back and tested for spark again. Now no spark at all! Checked power to coil, is there (again weak at 11.5 volts but there) and also checked ohms of coil terminals to their specs, all comes out fine.
What else can I check and what could be going on? I figure I can check the ECU and distributor but I don't know how to test them for proper function. I'm really confused at why I was getting random/intermittent spark and now no spark at all. Since upgrading to electronic ignition years back, I've never had trouble with it. I did think that maybe for some dumb reason the tach I'd recently installed was interfering since the one wire goes to the coil. But it was running with it hooked up and also I found no difference when disconnecting it today to troubleshoot.
In trying to make adjustments to my carburetor, something else has come up so now I can't tune the carb because the engine won't run!
The package: 71 Scamp, stock 318, 904 trans, 4bbl Holley 1850 carb with Weiand Stealth intake, upgraded to Mopar electronic ignition years back (4 pin, single ballast, orange box), with accel wires, super coil, and plugs. All else stock replacement or original. Oh I did add a Sunpro tach recently.
Car was running fine for the most part, hard cold starts and some backfiring through the carb so yesterday I took the carb off to make some bench adjustments to the fast idle and secondary plates. Put carb back on, cranks but no firing up. A few times it did actually fire up, but it ran REALLY bad and just barely (at around 300-500rpm) and would stall. Getting fuel, check. Getting spark...sorta. On #1 wire, I was getting what seemed to be an intermittent spark fire. When it did, it was a good blue spark, just not consistent it seemed. Last week I did have some issues with getting no spark at all, but after finding the main coil wire was not connected tightly, that seemed to do the trick.
Today I was trying to troubleshoot the problem some more. It seemed now though I was getting a consistent good spark but still engine cranks and does that "almost ready to fire up but not quite" routines. But it won't even fire up the least bit now. Checked power to ballast resistor and resistor ohms...all comes out fine. Power is a little weak at 10.5 to 11 volts (but battery is weak from cranking too, it is at 12.1 volts right from the terminals) and ballast ohms are 1.4. Went to get some dinner, came back and tested for spark again. Now no spark at all! Checked power to coil, is there (again weak at 11.5 volts but there) and also checked ohms of coil terminals to their specs, all comes out fine.
What else can I check and what could be going on? I figure I can check the ECU and distributor but I don't know how to test them for proper function. I'm really confused at why I was getting random/intermittent spark and now no spark at all. Since upgrading to electronic ignition years back, I've never had trouble with it. I did think that maybe for some dumb reason the tach I'd recently installed was interfering since the one wire goes to the coil. But it was running with it hooked up and also I found no difference when disconnecting it today to troubleshoot.
