• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Intialy car would idle now runs like crap

EccentricMagpies

Well-Known Member
Local time
4:13 AM
Joined
Apr 19, 2011
Messages
313
Reaction score
36
Location
Wisconsin
74 charger - 360 auto floor - rebuild with dyno.

I am left with adding trans oil to the trans but I need it to be running in neutral to ensure I have the correct amount.
Originally when I had it start it actually seemed to want to idle on it's own. (2 weeks back)
Since then it seems to run like hell and the only way to keep it running is to periodically pump the gas.
The one piece I did not replace, as far as electronics, is the coil. It just gets very choppy and won't remain running.

I'll swap out coils since that seems like a quick easy update but I can't be sure that is my issue. Anything jump out to anyone?
 
How many hours are on this motor? Is it fresh? Is it getting noisier too? Maybe you wiped a lobe or two
 
How many hours are on this motor? Is it fresh? Is it getting noisier too? Maybe you wiped a lobe or two

I guess I'm not sure how many hours would be a dyno of a motor unless the specs would indicate that?

but, yes, it's a new rebuild

Noisier would be hard to tell since i have to give it more fuel and it's running on open headers, it's definitely loud

It has the sound of mis-firing now so that is why i wondered it maybe the coil might just be junk?
 
Last edited:
Only time I had something similar was when carb had a bit of crap in it blocking idle port....


Curious... That was something I was going to just bring up.

I ended up having to replace the gas tank, sender, and fuel line because the old was completely unusable.
I also just installed a new fuel filter and fuel line to the carb. The one thing with the line to the carb is that it is braided with chrome, which I had to cut to length.
The one thing that bugged me about this line was getting a piece of this metal in the line. So I ran the fuel into a bucket prior to installing it...
maybe a piece stuck to the wall long enough?

This is a quick fuel carb... maybe i need to examine this.
 
Pull a plug wire at a time until the misfire is isolated. Pull the valve cover off when found and see it the rocker arms are all moving up and down with full deflection. A wiped lobe on a cam is going to happen almost right away (first 5-60 minutes of run time) and it can certainly cause a misfire. When a valve isn’t opening and closing it can pop through the carb, exhaust etc... also if a valve is stuck open that can happen too. All of which will cause misfire
 
Pull a plug wire at a time until the misfire is isolated. Pull the valve cover off when found and see it the rocker arms are all moving up and down with full deflection. A wiped lobe on a cam is going to happen almost right away (first 5-60 minutes of run time) and it can certainly cause a misfire. When a valve isn’t opening and closing it can pop through the carb, exhaust etc... also if a valve is stuck open that can happen too. All of which will cause misfire


thanks,
i'm going to try the carb first and then move to this. If it's the carb I think this might be hard to diagnose if I'm pulling wire by wire. It is to the point where I have to basically hold the petal to the floor just to get it to even fire.
 
When my 400 was doing this about a month ago it was the coil. It would run about 2 minutes tops then sputter and die. Now idles great.
 
Decided to try easiest solution to more time consuming solutions.

Just put in a new coil and it started with no effort at all. Idled just as it should. I obviously cannot take it for a ride since i'm still putting other things together so I'm going to assume this is fixed.

Thanks!
 
Auto Transport Service
Back
Top