Impala dies

sirstude · June 16, 2007, 12:38:31 AM

As you know, I have been chasing the electronics on the Impala for the last couple of weeks. I found that I had a bad coil and changed it out. Got the car running just great in the garage and then let it sit a few days. I took it out Tuesday night and it ran great, then started to miss a bit. By the time I got it home, I could not make it idle. I figured that the bad coil had messed up the electronic distributor module. Also, when I was driving it home it was missing quite a bit. I put in a new module (the old one looked burned) and it fired right up. However, when I tried to make it idle under 1000 rpm (it always idled at about 750) it would die. I messed with the carb for a while with nothing getting better. It is running about 6 lbs of fuel pressure and I checked the volume and got 3 inches of fuel in a 3 pound coffee can in 15 seconds. I then tried another carb that I had to make sure that was not the problem and still the same.

The exact thing that happens is if I keep the idle about 1000 it runs fine, drop it to 8-900 and it will run for a while and then start to die. If, I hit the gas a couple of times while it is dieing, it will run again. Otherwise, it dies and then lightly backfires up the carb several times and then stops. If I shut it off with the key, it just stops, without any backfires. It almost acts like it is running out of gas, but the float bowls are full (Holley 870 cfm carb). Until I changed out the carb tonight, it has been running this same setup for 3 years now.

Any ideas?

Doug

sirstude · June 16, 2007, 07:59:30 AM

The carb I changed was to a 780 I had to make sure that the issue was not with the 870 tha I have always run. Didn't mean that I put on a new carb and then this started. Going to change back to the correct one and take it for a drive this morning and see what happens. Might be that things are just loaded up from running it in the garage only.

Doug

UGLY OLDS · June 16, 2007, 08:31:34 AM

Sounds like you're getting a vacuum leak..Try covering the top of the carb ( or applying the choke) when it starts stalling...See if that speeds up the engine.That will richen the mixture....Maybe a vacuum line going bad??..Just a thought....

sirstude · June 16, 2007, 09:51:52 AM

Just took it for a drive with the idle up, drives great. Will see how it goes today and let everyone know. The surging and missing are definately gone with the new ignition parts.

Doug

EMSjunkie · June 16, 2007, 10:00:14 AM

Quote from: "UGLY OLDS"Sounds like you're getting a vacuum leak..Try covering the top of the carb ( or applying the choke) when it starts stalling...See if that speeds up the engine.That will richen the mixture....Maybe a vacuum line going bad??..Just a thought....

Thats what I was thinking too.............. careful, you're in the running for a "Team Smart" membership.

Vance

UGLY OLDS · June 16, 2007, 10:49:41 AM

Thats what I was thinking too.............. careful, you're in the running for a "Team Smart" membership.

Vance[/quote]

Not to worry...I'm sure I'll soon do something to correct that ... :? :? :oops:

phat rat · June 16, 2007, 08:06:33 PM

Quote from: "sirstude"Just took it for a drive with the idle up, drives great. Will see how it goes today and let everyone know. The surging and missing are definately gone with the new ignition parts.

Doug

It does run strong. I was with him on that little drive as he did a little showing of what that 502 can do!

sirstude · June 22, 2007, 10:14:37 PM

Finally running right now. I replaced the module in the distributor, changed carbs, changed plugs, changed coils, and checked for every possible vacuum leak known to man. Nothing. Today I stuck an HEI that I bought to use in the Olds and it runs great. I don't know what broke in the Accel electronic, but is sure was weird. Jack, it runs even better now with things set up right.

Doug

phat rat · June 23, 2007, 08:30:03 AM

Glad to hear you got it going right. So you changed all the wires huh. LOL
Well if I get out there again I'll have to have another ride to see the improvement.

Lakota · June 23, 2007, 08:57:59 AM

I've had the same problems with Accel in the past. Poor or sloppy idle, poor performance. Believe it or not, I got better results from a junkyard HEI.

Dave · June 23, 2007, 09:15:42 AM

Doug check this out.. Im sure its a good fix for your Impala.
Dave

http://cgi.ebay.com/ebaymotors/1976-76-Chevrolet-Chevy-Impala-DONK-24s_W0QQitemZ300122360635QQihZ020QQcategoryZ6169QQrdZ1QQcmdZViewItem

EMSjunkie · June 23, 2007, 10:07:42 AM

I can see Doug cruizin' around in that

Vance

58 Yeoman · June 23, 2007, 10:10:09 AM

Quote from: "jusjunk"Doug check this out.. Im sure its a good fix for your Impala.
Dave

http://cgi.ebay.com/ebaymotors/1976-76-Chevrolet-Chevy-Impala-DONK-24s_W0QQitemZ300122360635QQihZ020QQcategoryZ6169QQrdZ1QQcmdZViewItem

DONK??? Is that what they call them? To make that car look really cool, now it needs about a 6" top chop.

Glad I wasn't drinking coffee when I saw that auction.

phat rat · June 23, 2007, 10:47:39 AM

Quote from: "jusjunk"Doug check this out.. Im sure its a good fix for your Impala.
Dave

http://cgi.ebay.com/ebaymotors/1976-76-Chevrolet-Chevy-Impala-DONK-24s_W0QQitemZ300122360635QQihZ020QQcategoryZ6169QQrdZ1QQcmdZViewItem

I just got sick

UGLY OLDS · June 23, 2007, 10:57:52 AM

Quote from: "jusjunk"Doug check this out.. Im sure its a good fix for your Impala.
Dave

http://cgi.ebay.com/ebaymotors/1976-76-Chevrolet-Chevy-Impala-DONK-24s_W0QQitemZ300122360635QQihZ020QQcategoryZ6169QQrdZ1QQcmdZViewItem

Ahhh....The perfect Michigan "Deer Hunting" vehicle...GREAT ground clearance...Goes anywhere....