A great drive followed by a carb issue

[TRIPLE-GREEN]

Well I got my challenger back together after a cooling system overhaul. Drove the truck around a little and had no problem. On Sat I drove the car to work for the first time. It was about 15 miles. Not an ounce of trouble. in the afternoon it was a little warm but I took the car home. It drove without issue until I pulled up into the driveway. I pulled it out of gear and gave it a little goose. It reved up and then popped a little back fire. Then stalled out. I started it up again and it Idled really poorly. Then dropped it in gear and it stalled. If I have my foot on it, it runs ok, but when you let off it starts acting up. It is now not drivable because of this. What could be the issue?

I think it is my carb. I have a new air cleaner on it, it is 2-3 year old edelbrock carb. I played with the idle mixture screws a little but didn't see much improvement. Timing was good and all the parts seemed ok.

[Chryco Psycho]

my first guess is debris in the carb possibly flooding it , pull of the top take a look , check the float level mak sure it is clean in there .

[NCtrueconservative]

Well I got my challenger back together after a cooling system overhaul. Drove the truck around a little and had no problem. On Sat I drove the car to work for the first time. It was about 15 miles. Not an ounce of trouble. in the afternoon it was a little warm but I took the car home. It drove without issue until I pulled up into the driveway. I pulled it out of gear and gave it a little goose. It reved up and then popped a little back fire. Then stalled out. I started it up again and it Idled really poorly. Then dropped it in gear and it stalled. If I have my foot on it, it runs ok, but when you let off it starts acting up. It is now not drivable because of this. What could be the issue?

I think it is my carb. I have a new air cleaner on it, it is 2-3 year old edelbrock carb. I played with the idle mixture screws a little but didn't see much improvement. Timing was good and all the parts seemed ok.

I've had almost the exact same problem.  I cleaned out my carb one time...it was gummed up.  Worked good for a while, but then pulled the same stunt you described. Let me know if you find out whats causing yours. Someone told me to check the vacuum off the brake booster as well. 

[PlumCraZRT]

I did nothing else to the car but change the carb. Problem went away!

I think this is the exception, rather than the rule.

[Mopar73340]

The problem is it's an Edelbrock.  Get rid of it and get a decent Holley or Proform. I've read so many posts on carb problems with Edelbrock carbs. I had a terrible stumble problem with my old Edelbrock. I got rid of it and put on a Holley. I did nothing else to the car but change the carb. Problem went away!


                                                                          Matt B.

First off let me say I agree with Chryco.  Second don't take this the wrong way but anyone who makes the above statement doesn't know how to tune a carb. While I agree some do not like Edelbrock carbs, the only one I have ever heard of having trouble is the 1407/1411 750cfm. There are also many, myself included who do not care for the Holley style carb. To each his own. Also the Edelbrock carbs are very similar to the carbs many of our cars came from the factory with the AVS and AFB and these ran well and provided great service for thousands of miles and many years.   

[Chryco Psycho]

The AVS was decent , the AFB not so much , on large cam , low vacuum engines they are virtually impossible to tune , you cannot alter air bleed sizes etc

[Skunkworks Challenger]

Great looking car and CONGRATULATIONS on getting it going.  I agree with Neil on the carburetor problem.  Probably something floating around in the idle circuit passage ways that works it's way into the jets.  If you just blow the jet out the particle could go back into the cavity.  Try rodding it out with welding tip cleaners as well as compressed air.

[polarbear123]

I have an Edelbrock with the same problem. I had to advance the timing to get more vacuum so it would idle.

[Chryco Psycho]

advancing the timing should have increased the vacuum which is what the eddy carbs need

[NCtrueconservative]

I don't wanna hijack this thread, but I have almost the identical problem, so what helps me might help you.  I went out today and looked at the vacuum line from the brake booster to the intake.  Had a little tear where it went into the intake, so I took it off, trimmed off the bad and put it back on.  No help. Took the top of the carb off, cleaned everything good with gumout top and bottom, but it really wasnt that dirty, especially compared to what it looked like before I put a fuel filter on.  It still starts good, then dies the minute I put my foot off the gas.  My voltage gauge just drops.  Last time it did this, a fuel filter and carb cleaning helped, but this time idk.  I have a clear fuel filter so I can see the gas coming through.  I had a buddy watch it while i started and revved.  He said it squirted through there when I revved.  I would bet against debri in the tank, its new.  The gas I sucked out of the carb before I cleaned it looked a little watered down, but to could have been the water droplets still left in the water bottle I put it in.  Fuel pump bad maybe? How would one tell?  And like I say, it ran like a top, then gradually got to where it would barely idle, would backfire when going downhill, then finally got to no idle at all.  Idk what to check next

[Chryco Psycho]

try raising the floats slightly , Eddy recommends 7/16 , I would raise it 1/16 to 3/8 .
I sit dying at warm idle as well as cold idle , is the choke connected / working ? The rpm should come up 2-300 rpm when cold . loosen the screws holding the cover over the metering rods , are the rods staying down at idle or jumping up , if they are jumping you need lighter springs .
 raise the idle speed to keep it running , & start adjusting mix screws , timing etc & if you can get it to better start to lower the idle speed .

[06Daytona]

Check vacuum plugs on the front. My Eddy 800 has been blowing off the left side one and it runs like garbage until I put a new one on, then it runs fine again. It usually blows off after a backfire.

[Mopar73340]

I've tuned & rebuilt many carbs. Thanks for the presumption on my education/mechanical ability and particular problems with my motor. The #1411 750 cfm carb is designed for stock big block engines only. It doesn't play well with modified big cam motors that have a lower idle vacuum. That was part of my problem and why simply ditching the carb & installing one more suited for my motor worked. It has nothing to do with my lack of knowledge.

                                                                           Matt B.

First off you took things the wrong way as I figured you would which is why I started my post the way I did. Second You said the problem was because it "was an Edelbrock Carb". There was no mention of which Eddie carb he is running. If the issue was because it is an Eddie carb, they would all run bad. Not once did you say in your post that you tried to tune the Eddie you had you just stated you replaced it with a "Decent Holley or Proform" and the issue went away. While they are not suited for all situations, they do work good under most. By the way, I have run the 1411 you say is designed for a big block and most others complain about on a small block 360 with no issues.   

[TRIPLE-GREEN]

Trying to get a small leak under control. Not sure if it is the top bolt on the pump or the heater hose. I still have the original A/c Compressor on the car so it is making it a pain in the ass to see which one is causing the leak. What is strange is it only seems to leak when the car has been sitting cold. I get a little puddle on the top of the water pump. I will try and tackle the carb next. Thanks for your help. I will keep you guys informed.

[06Daytona]

In my personal experience I've found Eddy and Carter to be good stock replacement carbs out of the box. Bolt em down, set idle and go. For performance applications they do require some know how to get them working right and even then I don't think they're working at 100% efficiency. I've had nothing but problems using Holleys as stock replacements over the years, but for performance they're good as long as you take the time to tweak and tune. This is just me though, I prefer plug and play stuff. The 800 on my 440 was a simple bolt on and go, once a friend of mine came over and helped time and set A/F and idle.