Bogged down While In Gear And Sputtered During Acceleration

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anddddd maybe I spoke too soon. It is now back to falling on it's face when put in gear. I have not installed the new lokar kickdown cable so have not been able to go on a real drive yet. Initially after putting the new holley on it went around the col de sac without shuddering and everything seemed fine but after I tried to dial down the massive cold start idle (2300 rpms) it now is acting the same as before the new carb

The timing was wayyy advanced and after dialing it back down to 14ish it idles ok but shudders. Vacuum at idle is 17 and the gauge needle has a slight bounce (about .25). When put into drive or reverse the vacuum falls to 7ish.

I am really thinking timing chain skipped now. I have triple checked the gaps, plugs, wires, voltage, fuel pressure, tested for vac leaks, rotor...........I even checked the play of the chain by watching the rotor as I moved the crank bath and forth.
This is driving me crazy.

If the chain did skip, would the timing get retarded?
 
I never saw where you replaced the ECU. It was suggested in this thread. They will do just what you are saying. Sometimes it starts with hard starting, or maybe a sputter here and there, and some just drop dead. Try another ECU. My opinion of the orange box is the circular file. I had one, and a few friends have had them and they burn up within a year of steady driving.
 
Thanks for reminding me Gremlin before I get in deeper. I just ordered one and will see in a few days.
 
I always carry a back up box. I would run down to the local autoparts and buy one. I think I paid $10 for the last one I bought. Make sure they give you the correct pin ECU too. I had an autoparts try to sell me a 5 pin ECU and my truck had 4. I used to see a lot of cars at PYP that had new stuff bolted on, and when I saw the new ECU..I would pull the plug and sure enough...wrong one.
 
Was definitely the carb. Put the Holley on and now getting 20 Vac at idle. Took a short drive around the col de sac and no stumbling. Now I have to get a different kick down linkage and throttle cable.

Thanks so much for the input.

you should be able to use your original cable and kd linkage with an adapter from holley. I have one that I am not using that you can have if you want to pay shipping. Shouldn't be more than a buck or two. Pm me if you want it.
 
Thanks Harleydartguy. I already got the throttle and kickdown to replace the rod-type original but appreciate the offer.



Just Installed new ECU 4 pin (like the one it's replacing) and no difference.
 
Hate to say it, but this sounds like it is running just like my car was when I installed the timing chain a tooth off.

When I fired the motor up for the first time it started great, ran at 2000rpm for 20-30 min, started up again after letting it cool, but would bog and die as soon as I put it in gear. I was able to 2 foot it to drive it around the neighborhood a few blocks but it ran bad. As soon as I pulled in the garage and put it in park it would idle and rev like there was no problem at all.
I checked everything 10 times before I finally bit the bullet and pulled the front cover and saw I was a tooth off on the timing chain.

Even with the chain a tooth off I was able to set the timing at idle and at 3000rpm, and the timing did not move at all after I reinstalled the chain
 
My 4x4 started coughing and spuddering, on the way to the junkyard. It would die, crank up and I would slam it in gear to get down the raod to the next light. Finally I was cruising about 40 and Kaboom it quit. I pulled the fuel line and had plenty of gas. I was in a bad neighborhood and it was almost dark, so I had it toed home. I went through a couple of ECUs because you can get a bad one brand new in the box. A buddy of mine change 3 sitting in the auto parts parking lot before getting a good one. Anyhow, I could not get it to start. I had a lot of trouble from this motor anyway, so I yanked it and put the one from my Dart in it. It still wouldn't start. I ordered a whole new ignition system from ProComp Distributor, coil, and wires...dropped it in and it's still running. They use a module on the side of their distributor instead of an ECU...no ballast resistor. I saw a few people on here had problems with them after I bought it. I assume that is because the tang at the bottom of the distributor shaft is about 30 degrees from being in line with the rotor. I actually moved the cam gear a couple of teeth over to make the rotor line up with number 1. Crappy design, but once you figure it out it works.

Rice Nuker might be right with his suggestion. I saw you checked your fuel pressure, but I still wonder if the sock in your tank might be starting to gum up. Yeah, I had that happen before too. I took the air and pressured up the fuel line. Pow...blublblublublub, and I had plenty of fuel after that. It is pretty easy to pull the line out of the tank, and it won't cost anything to look if you want to do it the right way. With all the crap building up in your fuel filters, you may not even have a sock. You could undo the fuel line at the pump and the one at the tank and blow some air through it. Yeap, I had a tank with all the crap in it that would clog up filters and leave me on the side of the road. The last time the filter was solid black it was so full of crap. When I pulled the tank to clean it, I discovered the fuel line was really gummed up, like a clogged artery. The gas stopped flowing and the cars heart stopped. I replaced the fuel line and tank.
 
Seebee,nice diagnosis.Sounds like the Edelbrock,has something plugging the "main well" section.
 
BTW...isn't working on cars fun?
This was supposed to be a turn-key driver but instead turned into rolling restoration (money and time pit).
It was a gift from my wife so it's kind of a "gift horse" scenario. I do like working on it though. I've learned a ton of things forcibly by owning this one.

I'LL pull the timing cover and check the chain tomorrow. Thanks everyone for the insight and advice. I'll update in a couple days.
 
Here's my thoughts. You said it ran good right after you put the new Holley on it, correct?

Then a few days later it started running rough again, correct?

If it ran right for even for a brief time it's not a skipped timing chain. They won't jump back and forth.

Does it have a good fuel filter on it? If not your new Holley is full of crap just like the Eddy was. I love Holley's but have found them to be really touchy about small particles of dirt plugging passages. For that reason I always use a real good fuel filter that filters down to at least 40 microns.
 
Here's my thoughts. You said it ran good right after you put the new Holley on it, correct?

Then a few days later it started running rough again, correct?

If it ran right for even for a brief time it's not a skipped timing chain. They won't jump back and forth.

Does it have a good fuel filter on it? If not your new Holley is full of crap just like the Eddy was. I love Holley's but have found them to be really touchy about small particles of dirt plugging passages. For that reason I always use a real good fuel filter that filters down to at least 40 microns.

The new Carb has a Metal filter before the pump and a wix before the carb. FP is at 6.5.

I have yet to actually drive it with the new carb so I think I spoke to soon when the vacuum went back up to 18 and it went around the cul de sac.
 
So the update is this:

New Timing chain, timing tape, and reset everything to TDC.
New Rotor, Cap, Plugs
New Carb (Mentioned Already)
3rd ignition box

Fuel Pressure is still 6.5. Did a wet compression test last night and got 170 +/-7 on all 8. Checked all lash.

Fired it up today and still same symptoms. The vacuum wants to stay at 15 and bounce +/_1 when timing is below 20Btdc. At 20 BTDC the vacuum smooths out and goes to 19. I reset the air gap in the Distributor and noticed the magnetic pickup and the plate it is attached to has some up and down play. I'm starting to think the distro is not triggering the ign box correctly when the timing is set below 20 Btdc. Also timing bounces around below 20Btdc but smoothes out after 20'

Any thoughts?
 
I can't imagine how ignition timing would affect triggering of the ecu. Up and down play (springy feeling) is normal with the pickup as it's a spring steel clip that holds it in place. If it's actually loose it's a different story. 20 degrees atdc is very retarded. I'd be surprised it'd run good at all if it were actually 20 atdc. Do you mean 20 btdc? If it is reading 20 atdc when it runs right and your sure the balancer and timing cover are properly matched and the balancer hasn't slipped it is possible the timing chain jumped.

BTW: What cam do you have?
 
I can't imagine how ignition timing would affect triggering of the ecu. Up and down play (springy feeling) is normal with the pickup as it's a spring steel clip that holds it in place. If it's actually loose it's a different story. 20 degrees atdc is very retarded. I'd be surprised it'd run good at all if it were actually 20 atdc. Do you mean 20 btdc? If it is reading 20 atdc when it runs right and your sure the balancer and timing cover are properly matched and the balancer hasn't slipped it is possible the timing chain jumped.

BTW: What cam do you have?

Who are you calling retarded!

Belay my last I meant BTDC..........

3 Days ago I installed a double timing chain set and set TDC with a Piston stop and the balancer matched up so I'm 99% positive the timing marks are correct.

Here's the cam info and thanks for the responses.
b8b1f502-1.jpg
 
Who are you calling retarded!

Belay my last I meant BTDC..........

3 Days ago I installed a double timing chain set and set TDC with a Piston stop and the balancer matched up so I'm 99% positive the timing marks are correct.

Here's the cam info and thanks for the responses.

I wondered if it was just a typo. That's a pretty fair size cam for a 273 and will like a lot of initial timing to run it's best. The only problem is when you crank the timing up you crank up the total timing also so you have to limit it somehow, usually by welding up the advance slots. I didn't see where you said you put a timing set in it.

Just thought of one more thing. Are you still running vacuum advance? If so apply vacuum to the vacuum advance and recheck the reluctor gap. I've ran into a couple factory distributors that the gap closed up quite a bit when the vacuum advance came in causing it to run rough. A gap between .005 and .012 generally works ok so if it is closing up when the vacuum advance is pulled in set it then and recheck it after you unhook the vac adv to make sure it isn't real loose.
 
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