Hey all, I'm having an intermittant ignition problem. Started Monday morning...driving to work before the engine was all warmed up, sitting at a stop light it just died. Started right back up and ran fine. Did it again last night after sitting for 4 hours. Same thing this morning. Then this afternoon it was running great and I was doggin it around a backroad to deliver some drawings and out of nowhere it started heistating, backfiring, dying and starting back up again...the tach was all over the place. I pulled to the side of the road and the car just died. Got out, checked all my wiring and everything looked good. I slacked off the tension on the alternator (tightened sunday night) and the car started right back up...no problems on the way back to work. Almost problem free on the way home, one minor hesitation under mild load with the tach jumping again. I have a 62 caddy running a '64 429 with pertronix ignition and coil. Recent cap, rotors, plugs and wires. Good grounds and wires. I have no idea why this would be happening...coil going bad? Alternator going bad? Just pulled the cap and everything looks good. Any help here, sorry to be so long winded...just finally got the tranny backtogether and running well...feels good to be back out in the big boat. thanks bryan
wierd! put the points back in it, then it'll have an excuse to act that way. How's the igntion switch? the back came loose on the switch in my 55, caused some interesting problems like that.
Do check your tachometer connections. Also, what brand is it? Had a bad experience with a Sun SuperTach II some years back. Brand new out of the box and it would intermittently cause those same problems that you described. I totally disconnected it and the problem went away...so did the tach...I went the mechanical route with a Moroso unit...can't beat 'em. Hope this helps.
Thanks for all the suggestions, I'll look at the switch and disconnect the tach and go from there. I have to pull the distributor to put the points back in so that will be my last resort...at least I was smart enough to save all of those parts! bryan
man, this is weird took the tach out of the loop and ran fine for about a mile, then...pop, sputter, lurching...died again. Started it right back up and made it about 500 feet and it dies again with a big backfire. I'm stumped. Tightened up the coil connections and battery terminals and it fired back up and drove flawlessly a mile back to my office. would a clogged fuel filter be causing these kinds of problems? fuel supply seems fine, I have a elec. fuel pump that is working, there is gas in the carb. From what it's doing at random intervals I wouldn't think it would be the pertronix kit...seems if it was dying it would just go? Any other thoughts besides put some points back in? thanks guys bryan
My petronix coil turned itself into a diode. It would be fine cold then once it warmed up it was toast. Don't know if that's a common problem or not, but its a place to start.
Nope. Sounds like a electronic fault, possibly related to heat, or vibration. Putting the points back in will eliminate the Pertronix as a suspect, AND be easier to diagnose as well. You DO have a ground cable from the battery DIRECT to the engine block, don't you?? AND a cable from the block to the car body?? Lack of good ground can cause all sorts of weird problems. Cosmo
yup, have good grounds. Also checked by ignition switch...all good there. going to pull the distributor tonight and put the points back in, just have to find them! Also going to pull the alternator and have it tested but I dont' that that is the problem...also swap the coil thanks all bryan
Just to confuse things, I have seen clogged filters act exactly like that--a really bad one won't pass the fuel as fast as the car burns it, but after the stall the residual pressure from the system trickles the bowl full and the thing will run again as far as one bowlfull will carry it. cloged tank vent produces same thing in slow motion. Most GM filters have a blow-off spring to allow flow around clogged filter, but I have never known that to function--a good thing if lots of crud is circulating right now. I have had one instance of instant filter clog after buying gas--my car with fresh filter stopped about half a mile from the gas station with filter full of red paint flakes and rust. Took three filters to get me through that tank of gas and eliminate most of the crud--I suspect I bought gas right after a delivery, and all the crud in the bottom of a rusty underground tank was stirred up by the flood of new gas from the truck.
Bruce now that I think about it, problems started monday after I filled up with gas...going to replace the filter(s) anyway. I have one before my fuel pump and one before the carb. thanks
my chrysler did something like that last summer, but without the sputtering & popping. id be at a red light & it would just die. everything, not even a click when the ignition was turned. i jumped out & jiggled all the wires & she fired right up. not sure about caddys but i know old chryslers notorious for crappy grounds. thats exactly what it was, dirty loose grounds at the alternator, firewall, coil & battery. funny that i replaced all those things over the years & then i thought id never had to touch them again since everything was new & rewired, didnt think about the fact that ive been driving this thing daily for over 6 years. oh, yeah. im also running a pertronix ignition & coil. not one problem with them since i installed them. im sure you could try to hook up the stock coil again or even a new stock one i think might be less than $10.
try some drygas too. you may have got a bad batch of fuel with moisture in it. unless somewhere along the line you made an enemy & they pissed in your tank or something.
You can check at least paper filters by blowing through the hole (except for late model ones with the pop-in plastic check valve--pull that out for the test.). A good filter will be relatively easy to blow through, and most that are hard to blow through will still run the car. When you feel your eyes bulging out instead of air going through, you're a pedestrian. Buy a couple spares in case you did get a whole tank full of debris...
Hey Bryan, I think Bruce Lancaster is steering you in the right direction here. I just had the EXACT same problem with one of my unmentionable daily-drivers. Crud in the tank was clogging up the filter, causing it to sputter, stall etc. Rev's would jump erratically as a bit of fuel managed to get through. I thought it was an ignition problem. Turns out the tank was full of crap. I believe that when the car stalled it was allowing the fuel with crud/blockage in it (before the filter)to run back into the tank. Then it would start up and run fine until some more crud got drawn up into the line and clogged at the filter. Cleaned the tank, changed the filter, added an extra filter and some new line. Problem solved. Sounds like you may be in the same kinda situation. As you mentioned, you were going to replace the fuel filters anyway...I'd do that first. Good luck. silas
guys, thanks for all the suggestions and help. got the wife coming to pick me up as I don't want to be drivng home in the dark with my 5 year old and have the car clunk out on me. as the problem seems to be getting worse I would guess it's a filter now...who knows? ;-) Going to start with the fuel filters, I've just got some of those sealed metal purolator units. Then the coil then the points the HAMB is great...HAMB is good... b
Many '50s-'60s GM cars have several multi-prong wiring harness connectors on the firewall that can give this problem. They never get any attention after the car leave the factory, so they'll sometimes work loose or get that green moldy looking stuff growing on the plugs. Even if this isn't the problem, a cleaning isn't a bad idea. 302
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