Suddenly running like crap, where to start.

[Leviticus]

Hey guys,

Been a while, been busy with work and have been ignoring my truck. So I fired her up the other night and she was running great like usual and took her for a spin. She was great until I pulled in the driveway and was getting ready to shut her down and gave it a little rev and all of a sudden the idle drops to 500 from 850-900 in park with a rough idle and shaking all over the place.

Now it will start but doesn't want to stay running when cold and gives little pops in the exhaust when giving it a little gas.

Haven't had much time to dive in deep, but checked the timing and it was a little off what I had set it at so re-set it and though I had it... nope. pulled the fuel filter and bypassed it, and seem to be getting spark at all cylinders.

What I did notice is that when I pull the air filter and either choke it 80-90% or cover the intake with my hands the idle comes up and it runs smooth. Maybe too much or too little fuel? Or a leak somewhere in the intake manifold? What would cause that?

Putting a mini starter in tomorrow, and fixing this issue. Where wold you guys start? Also it has an electric fuel pump and I haven't had a chance to check fuel pressure.

[CG]

Maybe one of the rubber vacuum line plugs on the carb?

[Gobbles]

Im with CG on starting with the carb. Check for any fuel leaks through the needle and seat as well, I had a similar problem which ended up just being a small gas leak.

[too much stuff]

Sounds like it is sucking air from somewhere. Carb gasket or a vacuum line?

[Leviticus]

Well, I found one problem but not sure it was it. I guess my fuel filter exploded inside and was running a bunch of crap through the lines. I pulled out the filter and bypassed it, pulled the screen out of my edelbrock and it had a bunch of clear plastic crap and some small metal shavings. Started it up and its doing the same thing as before, so its either now pushed that crap past the screen and its in my carb, or there is a vacuum leak somewhere.

The vacuum to my crankcase, hei and brake booster all seem fine and my ported port is plugged. So its either the carb gasked, or intake gasket or there is crap in my carb.

How hard are the edelbrock 1406 carbs to clean? Anyone know of a sticky or a manual on cleaning them?

Crap, lots of work for me tomorrow...

[jcis4me]

Aloha
I am running an Edelbrock 1406 carb with a 1" riser on my 350 it does the same thing, from time to time, I find a safe place to pull over and back out the Idle screws and then back in and the problem goes away. I have two fuel filters in line but some how a bit of rust gets by the filter, both filters have reddish looking substance in them. I pulled the fuel pick up and it has a bit of rust on it, so I have a feeling the rust is in the carb and getting stuck in the idle circuit because when I back out the idle screws the problem goes away. Looks like a new fuel sending unit is in the future.
The carb is easy to clean out, just remove the two screws on the top sides of the carb, be careful not to bend the metering pins, then remove the springs they fall back into place when you put it back together. Then take out the screws holding the top of the carb out and you will see the floats they remove very easy clean out your bowls and put it back together the way you took it apart. I went to my local speedshop and bought a rebuild kit and it had an exploded view of the carb and all the parts you need to rebuild it. The carb also has torx bits inside holding the fuels squirters in place if you choose to rebuild it, I used the gasket and the new acc pump fixings, I bet it just has some junk in the jets as they are on the bottom of the fuel bowls. Hope this helps
Aloha
Marty

[jcis4me]

Try here...
http://www.edelbrock.com/automotive_...ers_manual.pdf
Page 20 and 21

Marty

[Leviticus]

The idle circuit was clogged got it all fixed up, thanks guys!