Slant 6 dies when driving

-
Valsig66

Valsig66

Active Member
Joined
May 10, 2017
Messages
43
Reaction score
10
Location
El Monte
Got a problem with my slant. On my way to work it just died.i kept cranking it too see if it would start but eventually i killed my battery so i got a new battery, new battery same problem.after the new battery it will only click no cranking .i figured lets change all electronic componets.so now i replaced starter,starter relay, ballast resistor, ecu module, battery. Alternator and voltage regulator are 2 months old. When the car does turn on i unplugged the positive for a second to see if the alternator is charging the battery and it is car doesn't die. But now a days even a brand new part is sometimes faulty .anyone have any ideas what i should check next? Thanks in advance
 
Any engine needs 4 things to run..
Spark
Fuel
Compression
Be in time
If it quits running one of them is missing.
I always check fuel first. Does it have accelerator pump shot?
If it does I check to see if it has spark.
If it does I check to see that its still in time.
Compression, You can usually hear when it's cranking whether it has compression or not.
 
Im getting enough fuel to my carb because the gaskets are wet and i see the squirt in the carb. The thing is sometimes the car runs for at least 15 minutes then it will die. When i try to start it back up it just cranks no start
 
1973 and up electronic dizzy bad pick up coil. One of the first symptoms of a bad ignition pickup is an engine that stalls. An old or failing ignition pickup may cut out signal intermittently, which may cause the engine to stall. The engine may suddenly just shut off, almost as if the key had been turned off. Depending on the nature of the issue, sometimes the vehicle can be restarted and driven again after a brief period of time. However, this problem will persist and worsen until it is taken care of.

pick-up-plate-wire.jpg
 
Slantsix64-Do you think that sounds logical for my 74 also. Mine is hesitating really bad, but only after it has been driven for about 20 minutes? I have replaced many things too
 
Need more info. What ignition system?
His Avatar indicates a 66 Valiant. Unless it's been converted to electronic ignition, bad pick up coil does not apply because it doesn't have one.
I agree with Bad Sport about a bad coil affected by heat as it warms up.

Correction: after rereading original post, He did replace ECU.
 
Last edited:
TF360 said:
Slantsix64-Do you think that sounds logical for my 74 also. Mine is hesitating really bad, but only after it has been driven for about 20 minutes? I have replaced many things too
Click to expand...
Check the carb. If its dying when you dip the throttle... the pump shot isnt there. Notorious on 1920 holleys
 
No mine runs great when cold. After about 20 minutes or so she starts hesitating. I did replace the coil and the carb- didn't change
 
TF360 said:
Slantsix64-Do you think that sounds logical for my 74 also. Mine is hesitating really bad, but only after it has been driven for about 20 minutes? I have replaced many things too
Click to expand...
Its hesitating? or will it die after being driven for a bit?
 
It hesitates and eventually will die, but will start right up and continue to hesitate. If it cools it will run smooth again for a while then if going from light to light the hesitation will begin again. It's a 74 with California emissions. Almost seems like a vacuum leak, but I don't see any broken lines.
 
TF360 said:
It hesitates and eventually will die, but will start right up and continue to hesitate. If it cools it will run smooth again for a while then if going from light to light the hesitation will begin again. It's a 74 with California emissions. Almost seems like a vacuum leak, but I don't see any broken lines.
Click to expand...
hm maybe , but get a spray bottle with water in it and spray around the carb and intake were it meets at the head see if you hear any drop or change in idle you have a leak. i think it might be the pick up coil, i would replace the distributor and mopar ECU Box at the same time and see if it helps.
 
Also i would get rid of all the smog stuff and plug them up with vaccum caps just to eliminate all that.
 
TF360 said:
It hesitates and eventually will die, but will start right up and continue to hesitate. If it cools it will run smooth again for a while then if going from light to light the hesitation will begin again. It's a 74 with California emissions. Almost seems like a vacuum leak, but I don't see any broken lines.
Click to expand...
Vacuum leak can be inside a component too. The 74 had all sorts of emissions crap on it. More so for C.A.P. Some things didn't receive vacuum until the engine warms. EGR valve and spark advance for examples. Back in the day just pinching hoses with needle nose pliers would pin point the culprit. Today that might crack rotten hoses too. Good luck with it.
 
Buy a cigarette lighter voltmeter to monitor while driving. $15 digital display on Amazon or Harbor Freights cheap $6 one. Should see 12.6 V when off (battery full charged) and ~14.3 V when driving. At least your early fussing was with battery and charging. Such meter is essential for new cars since they give no dash monitor. I use in my 2002 T&C when I suspect charging problems (worn alt brushes recently) and try to monitor on long drives so we don't get stranded again (belt slipping at alt due to bad p.s. pulley). To determine O/F problems, see if a shot of starter fluid down the carb throat smooths it at idle. If so, you may have an air leak.
 
Slantsix64 said:
1973 and up electronic dizzy bad pick up coil. One of the first symptoms of a bad ignition pickup is an engine that stalls. An old or failing ignition pickup may cut out signal intermittently, which may cause the engine to stall. The engine may suddenly just shut off, almost as if the key had been turned off. Depending on the nature of the issue, sometimes the vehicle can be restarted and driven again after a brief period of time. However, this problem will persist and worsen until it is taken care of.

View attachment 1715266239
Click to expand...

Copy n Paste Momo lol
 
Valsig66 said:
Got a problem with my slant. On my way to work it just died.i kept cranking it too see if it would start but eventually i killed my battery so i got a new battery, new battery same problem.after the new battery it will only click no cranking .i figured lets change all electronic componets.so now i replaced starter,starter relay, ballast resistor, ecu module, battery. Alternator and voltage regulator are 2 months old. When the car does turn on i unplugged the positive for a second to see if the alternator is charging the battery and it is car doesn't die. But now a days even a brand new part is sometimes faulty .anyone have any ideas what i should check next? Thanks in advance
Click to expand...

Happened to me before, bad coil.
 
Had a rotor do this too. Blew a hole through centre and would short through to dist shaft.
 
Can also be the distributor pick up coil opening when it gets hot, gives the same symptoms.
 
TF360 said:
It hesitates and eventually will die, but will start right up and continue to hesitate. If it cools it will run smooth again for a while then if going from light to light the hesitation will begin again. It's a 74 with California emissions. Almost seems like a vacuum leak, but I don't see any broken lines.
Click to expand...
My 76 Aspen /6 did a similar thing and turned out to be a massive vacuum leak in the vacuum advance unit
 
Could also be a bad ballast. Always have a spare in the glove box. Or convert it to a jumper wire and eliminate the ballast.
upload_2019-2-18_0-3-20.jpeg
 
Last edited:
You must log in or register to reply here.
-

Back
Top