Ignition problem... someone please please please help me!!!

[xtreme80]

Here's the scoop. 1980 C10 w/ a 350 crate with about 1400 miles. New tranny. New Edelbrock carb.

During heavy driving where I reach higher speeds, it seems as if my ignition is cutting out. It will run fine till it peaks in first gear, and right before the shift, it starts this hesitation which feels as if Im letting off then accelerating, then letting off, over and over again. Soon as it shifts into second it completely bogs down and feels like a 4 cylinder. It sputters and chokes till I let my foot off the gas. If I keep my foot in it, it'll kill the engine. Even when I let off the gas, it still takes about 5 seconds before it runs normal again. I'm nearly 100% positive it's an electrical issue, and some sort of ignition problem.

Here's what I've done so far to diagnose this problem:

New distributor assembly, pickup coil, etc. New HEI coil, new cap, rotor, plugs, wires. Replaced the distributor power wire. None of these seemed to help the slightest bit.

Here's why I know it's not a fuel issue:

Checked the fuel filter and I can blow through it with no problem. It's also brand new. All my fuel lines are brand new. I wired in an inline secondary fuel pump to help with fuel movement through the lines. Lastly, I hooked up a propane bottle through one of my vacuum lines, and drove down the road shooting propane into the engine. If the engine was being starved for fuel, there was enough propane running through it that it would have fixed the problem temporarily.

It's getting worse and worse too, now it's sputtering during everyday driving, when I accelerate, and I'm afraid that in the next few days it's finally gonna stop running...

Someone please help!

[shadetree]

It might be a mechanical issue, too. Try hooking up a vacuum gauge, so you can see the gauge while driving. If it drops drastically when the problem starts, I would check the EGR valve.

[xtreme80]

EGR isn't hooked up, but hasn't been since I've owned the truck, and it's never come close to doing what it's doing now.

Thanks for the advice though! I appreciate it! (not sarcasm, just in case it sounds like it)

[grinch4om]

do you have a cat converter on it? sounds like one is plugged up, gets worse as it warms and eventually cloggs completely. try unhooking it and drive. if you by chance have the original pellet type, take it off and replace it with a high flow one. On another note, hook up a fuel gauge, drive it and glace at it when it hesitates. You may have a delivery problem. It does not sound electrical to me also make sure the rockers aren't too tight, lifters could be pumping up at higher rpms and hanging open the valves

[Pyrotechnic]

Check to made sure the metering rods in the carb are moving up and down freely. Sometimes they get bent off to the side and don't go down in the jet. It caused my new engine to run really strangely. Even if it is a new carb, my brand new Edelbrock carb had this exact problem right of the box.

[lurch115]

i'd half to agree that its a fuel issue....other things to check would be the choke flaps for the secondaries if you have the q-jet on it yet.... if the back to screws that go all the way through the carb. get over torqued (it doesn't take much) the secondary choke flaps will bind and not open and that would give you the same senerio as you have now...cause it sounds like your engine is flooding out... if they are binding....take the carb. off and file the areas where the secondary choke flaps are binding untill they no long do....should be able to just tap them and they should pop open and then back shut

[xtreme80]

Im still stuck on the idea that it's an ignition problem. I also dont have a q-jet anymore, it's got an edelbrock now.

One of the techs at my work is going to take a look at it tomorrow morning when I get to work, so if he can figure it out after a test drive, I'll let you all know.

I think part of the problem is that I'm not explaining it right. I know in my head what it's doing, but getting it written down is another story.

[Slonaker]

It sounds just like what mine did when the fuel pump was going out. I replaced the pump, and it has been fine ever since. I'm not saying it is your pump, but that it sound like it does not get enough fuel at high RPM.

Slonaker

[xtreme80]

Fuel pump is brand new. replaced when I put in the crate.

And I keep saying, it's not a fuel problem. We hooked up a propane bottle through a vacuum line, and turned it on when I punched it. If it was a fuel delivery problem, the propane would have kept it from "stalling out" like it did.

[ureckme]

Hay! it's hard for me to look at that truck if you don't call me or PM. Lets take a look at that truck and get it fixed.

Matt

[87 STEPPER]

That edelbrock carb probably has an electric choke make shure the choke isn't getting power to it all the time.

If so thats gonna be the problem.

Check to see if it still has pwr. once the engine is @ operating temp. there should not be 12v out there at that point.

[piecesparts]

Does this happen on ALL accelerations or just ones that happen when you are cruising around city streets and then try to "Jump On It" when you come to an open area. It sounds as if you are getting some fuel vapor binding. I had a similar situation shortly after my last rebuild and I put on a new fuel pump and fuel lines. I was using an Edelbrock fuel pump WITHOUT the factory recirc line back to the tank from the pump, like my factory pump had. Every time I accelerated the truck would bog really bad. I solved the problem by putting a different plate on the fuel pump bottom and reconnecting the recirc line to the fuel tank.

[xtreme80]

Originally Posted by ureckme

Hay! it's hard for me to look at that truck if you don't call me or PM. Lets take a look at that truck and get it fixed.

Matt

Thanks man. If the techs at work havn't come up with anything, I'll let you know and maybe we can set something up.

Thanks for the replies everyone else. I appreciate everything.

[wedgemon]

* Check floats
* Check fuel pressure. about 5 psi MAX for Edelbrock 1400 Series
* What Carb?? 600 CFM is about right.
* And, vacuum - as stated before me.

I know you think electrical, but, if you have spark, you've already eliminated that.

- Dave

[xtreme80]

Originally Posted by wedgemon

* Check floats
* Check fuel pressure. about 5 psi MAX for Edelbrock 1400 Series
* What Carb?? 600 CFM is about right.
* And, vacuum - as stated before me.

I know you think electrical, but, if you have spark, you've already eliminated that.

- Dave

I have spark but I have no way to check to see if I have spark when this stuff happens...how can I check that? I have spark when the engine is off and I try to turn it over...

It's a 600cfm edelbrock. All vacuum is good, triple checked it.

[xtreme80]

I'm embarassed to say this, but I guess the decent thing to do would be to post my findings...

To everyone who said it was a fuel issue, you were correct in the fact that it was a fuel issue. To everyone who said it was a flodding issue, you were wrong. Sorry.

So here we go, the embarassing part.

A kinked fuel line.

Damn, you know, that is almost too obvious.

We got the kink taken out of the line, and it runs much better. It's still got a hiccup at cruise speeds, so Im gonna go ahead and replace all the fuel lines, and see if this helps the hiccup. If not, I'll be asking for help from ureckme!

[xtreme80]

Diggin up an old post here just to show everyone my findings.

It seems I must have had two problems with the truck.

First problem: The sock that acts as a filter on the gas tank sending unit was worn bad. Just holding it in my hand, the sock was breaking off in tiny pieces. I'm sure that was clogging things. I replaced this, along with the fuel lines and fuel filter.

Then I start the truck up, and it runs even worse than it did before. Misfires real bad when in neutral and revving it up. It was horrible.

Then I remembered what ureckme had told me over the phone the night before. He mentioned trying to unplug the vacuum advance on the distributor and see if this makes any kind of difference.

Well whaddya know? Unplugging the bastard worked! Turns out that my remanned distributor that I put in last week is bad. Now I just have to prove this to the parts guy.

I've been jumping through hoops and tearing this truck down trying to fix this problem, and I think it's finally coming to an end. The truck runs better, gets better gas mileage again, and hasn't even come close to acting like it used to... (knock on wood)

Just thought I would let y'all know

[lurch115]

*LOL* speaking of that sock filter that is supose to be in the tank.....about 6 months ago i was having a similar issue with my truck and replaced the pump.....no change...so i figured what the heck, i'll change the 3 month of fuel filter.....pulled the line off that comes up to it from the fuel pump and guess what i found! that little filter sock was plugging up the fuel line right before the inline filter!! what i wanna know is how it made it through the tank switch, all that fuel line, the pump and couldn't make it into my clear inline filter!!! would have saved me so much time and hassel

[xtreme80]

That'll do it man.

What I did was I completely ripped the sock off the pickup tube in the tank,and put it all back together. Turns out there must be enough deposits in the tank to clog the fuel filter, cuz it's stalling again, but installing a new fuel filter is fixing it, at least temporarily.

The sending unit was on backorder, so it won't be here till this thursday. When it comes, the tank is getting drained, cleaned out, and a new sending unit is going in it. Then all the fuel lines are getting replaced, and a new pump and filter are going on it. By the time I'm done, all I'll need is a new gas tank, and the entire fuel system will be brand new.

[lurch115]

i'd just spend the extra 100 or 200 bucks and put a new tank in it....

[xtreme80]

That's easy to say when you're not a broke 20 year old working for far less money than you should be and are already in debt for your truck...

haha