73 Dodge polara 440 x police

Mopar nut

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I hope i can get some help. 1st i need to know if anyone knows were i can get a under hood engine wiring harness.
next, had the engine rebuilt 2 years ago. Last fall i was taking a ride before i would put the car away for winter. I was on the hi-way for about 65 miles,going about 70 MPH it was about 65 degrees out. All of a sudden, the engine was shacking & bucking then very bad back fires. I thought the motor blew. I pulled over and it died. I did get it start up,seemed ok , i started driving again & then it did it again.
I pulled off the road let it sit for 20 mins. I drove back home a a slower speed and did not have a problem. So what caused this to happen? It is the timing? Did the motor get so hot that it predesignate ?
 

Davea Lux

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I hope i can get some help. 1st i need to know if anyone knows were i can get a under hood engine wiring harness.
next, had the engine rebuilt 2 years ago. Last fall i was taking a ride before i would put the car away for winter. I was on the hi-way for about 65 miles,going about 70 MPH it was about 65 degrees out. All of a sudden, the engine was shacking & bucking then very bad back fires. I thought the motor blew. I pulled over and it died. I did get it start up,seemed ok , i started driving again & then it did it again.
I pulled off the road let it sit for 20 mins. I drove back home a a slower speed and did not have a problem. So what caused this to happen? It is the timing? Did the motor get so hot that it predesignate ?

There are a lot of things that could be causing the symptoms you describe. The backfiring and missing could be a classic indication of a bad coil. If the coil is not wired properly thru a ballast resistor, it may be overheating and crapping out. This is an electronic ignition system so check the following. The electronics require a good ground. Check both battery cables and clean if necessary. Check the brain box for the electronic ignition to be sure it is also well grounded. Run a continuity test on the ballast resistor. As this condition seems to happen after the car has fully warmed up, you could also have a bad pick up module in the distributor. Next check you fuel filter to be sure it is not clogged up. Do these things and report back. Do not replace any parts until you have isolated the cause of the failure. If you do not already have one down load a FSM (Field Service Manual) for free at www.mymopar.com The manuals are in the tools reference section from their home page.

Dave
 

Mopar nut

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There are a lot of things that could be causing the symptoms you describe. The backfiring and missing could be a classic indication of a bad coil. If the coil is not wired properly thru a ballast resistor, it may be overheating and crapping out. This is an electronic ignition system so check the following. The electronics require a good ground. Check both battery cables and clean if necessary. Check the brain box for the electronic ignition to be sure it is also well grounded. Run a continuity test on the ballast resistor. As this condition seems to happen after the car has fully warmed up, you could also have a bad pick up module in the distributor. Next check you fuel filter to be sure it is not clogged up. Do these things and report back. Do not replace any parts until you have isolated the cause of the failure. If you do not already have one down load a FSM (Field Service Manual) for free at www.mymopar.com The manuals are in the tools reference section from their home page.

Dave
the battery cables are new as is the distributor
 

polarus

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If you have your old harness you can send it to Bill Evans, he can make a new harness using your old one as a guide.
 

halifaxhops

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Check the pick up in the distributor when hot. New ones suck.
 
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I've experienced kinda similar issues when my fuel pump partially failed (the spring broke but still pumped a little at very low pressure) it only supplied fuel at low RPM, at freeway speeds it would effectively ran out of gas, but as soon as I pulled over, it picked up and ran OK.
My $.02
 

MoparapoM

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Ignition Coil. And do NOT buy a 'Cheapo Chinese' fake one. You are FAR better off scavenging an ancient OEM MoPar coil from the salvage yard.
 

saforwardlook

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I thought I read not too long ago that Bill Evans was no longer making wiring hanesses?
 

WissaMan

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Make sure you have the proper gap between the reluctor and pick up. When I got a new electronic ignition kit for our 68, I just dropped it in without checking that gap (my bad). I had some weird problems with it not starting right (it would on catch and start after you let go of the key, not while you were cranking it with the starter). The ignition timing was not stable either as when I'd check it with a timing light, the timing mark on the pulley would jump around. Turns out that gap was way too wide out of the box. Once we set it according to the spec in install manual everything was great. Since yours was ok for 2 years, this might not be the case, but it's worth checking if you haven't already.
 

ayilar

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Any experience ordering battery cables from Mr. Evans? I need a positive cable for Snow White (P/N 2983499 ), and his company makes them.
 

ayilar

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@polara71 -- why the disagreement? He emailed me that he does make that positive battery cable.

Or, are you referring to this thread discussion?
 

polara71

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Then I hope you are happy and I am wrong. He is a regular vendor at Carlisle. When I have asked he has told me no he doesn't.
If indeed he has the 100% correct cable with fusible link, please let me know asap. Missouri needs one bad ...
 

ayilar

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I've asked him for a photo, precisely for that reason. Can you check the P/N that I gave above ( 2983 499 ) is the one on your Polaras?
 

ayilar

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He has told me explicitly, twice, that he has the correct cable for a 1970 Polara with V8 and the above part number. I’m ordering and everyone will know if it’s incorrect. I’m betting it’s correct.

PS: is the fusible link part of the cable? He adds it as an option.
 
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polara71

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He has told me explicitly, twice, that he has the correct cable for a 1970 Polara with V8 and the above part number. I’m ordering and everyone will know if it’s incorrect. I’m betting it’s correct.

PS: is the fusible link part of the cable? He adds it as an option.

Take the option, and a photo... please to share with the world.
 

ayilar

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Here you go:

IMG_1306.jpg


IMG_1307.jpg
 
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