Well, it did it again.

I pulled up to a stop light yesterday and when the light changed green and I gave it gas, the car stalled a bit, the rpm's kind of leveled out like the car was stuck at 900rpm, it would run fine (or sound like it) when I hammered the gas, it would sputter, rev high, then act like it was stalling out, but had no power, it would come in spurts. I pulled over to the side of the road and it wouldn't idle, just died. Ran rough, sputtered, then would die. Start up just fine, I'd rev the gas and it would sound like it mis-fired then idle down and stall out. Couldn't keep it running. Had to feather the gas to keep it idling. Once I got it rolling to get home it would accellerate but she was running hard, nearly had her floored to get to 60mph.

Fuel Pressure is good, fuel filter was clean. Three weeks ago it was running good and I got it Dynoed. Now I'm not sure where I should look. It's acting like I broke another valve spring (number 5 since swapping in this 350 for my old 305.), got the drivers side off and nothing is broken there. Going to dismantle the smog stuff and take a look at the passenger side tonight. If it's not another broken valve spring, any ideas? EGR? Transmission? Would a bad Torque converter do this? I'd think it would still idle fine even if it was.

I'm just ready to sell the stupid car just to get rid of it. I've put nearly $10k into this stupid engine build/swap and other upgrades and I can't keep the car running for more than a week at a time since the new motor went in. Was supposed to be in a local car show next weekend but I doubt that is going to happen. Had a car club cruise I missed this weekend because of it as well. Really frustrated right now. Any help would be appreciated. Thanks.

 

Would spark plug wires shorting out cause symptoms like that? I just pulled the #5 and #7 plug wires and the boots on both are cracked all the way down to the center conductor at the 90* corner of the boot.

 

Not necessarily, It would sputter all the time, a consistent sputter, never solid. Than happened to me one time when number 8 got fried against the header, replaced it and no problem. When you say fuel pressure is fine, what do you mean? Do you have a carb? Try not to get too discouraged, same thing happened to me about 2 years ago, finally figured that it was my fuel pump, fixed it at a low cost and car has been running consistently, I would say even dependably, ever since.

 

I pulled the valve cover and the valve springs don't appear to be broken but I can't see the backside of 5 and 7 cylinders because I cant get the valve cover all the way off. I can't see strait any more because it's now 6am, so I'm going to pull the EGR and actually remove the valve cover to be 100% sure later today.

I do have a carb, 84 T/A's had Electronically controlled Carbs. They didn't put EFI in the T/A's until 85.

I am going to have to try a new set of plug wires now anyway and if that doesn't work...?

 

What's the progress? Any Change?

 

Anytime I see cracking or whiteness in a spark plug wire, I automatically replace it. I've had symptoms similar to yours where the car stutters, jumps, etc because of 1 or 2 bad wires. The solution for me was to make sure the wires were far away from the headers, zip tied, and spark plug boots. Never had the idling issue though...

 

I took off the EGR valve and finally got the valve cover actually all the way off. Man they could make things easier to get to. Anyway, I don't see that any of the valve springs are bad...that said, I'm going to assume my problem is spark plug/plug wire related. Only problem now is I just don't have a set of spark plug wires laying around. I ordered a new set of MSD wires from Summit today and should be getting them on Thursday or Friday. ONce I get them I'm just going to hook everything to see if that was the problem.

for the plug wires themselves, I didn't see any obvious damage. These wires are red with the grey boot cover over the end and it was that grey cover that was actually damaged all the way through. If both 5 and 7 were shorting out to the headers then that would definitely cause an issue wouldn't it? Might even be causing the idle issue if they are dropping out enough spark to keep the engine from firing in those two cylinders....maybe. Could be I have more than one problem...hopefully it's just one.

 

That could be the problem completely. I would replace those two first just to confirm your diagnosis. Get boots for those wires for sure and make sure the other ones are not going to suffer the same fate.

 

I know this is an old topic put it describes my problem exactly. just wondering if i can get an update on if replacing the plugs and wires worked

thanks

 

Ok, sorry for the long delay in posting.

The new plug wires seemed to have helped some...but it hasn't fixed all of my problems. Still running rough at idle. Tried swapping back to my old original carb and that cleaned things up immensely, though now I'm throwing a lean/rich code becaues thsi carb isn't tuned to the motor. drove great for two days, then died when coming off the off-ramp from the freeway. Now it won't start unless I pour gas down the carb and if I let it idle under 1800 by taking my foot off the gas it dies and won't re-start unless I pour gas down the carb. I ran it up on the freeway this way and it runs great at part throttle and full throttle...but at idle it just dies. This was October...parked the car and haven't touched it since other than messing with it here and there. Nothign I do seems to make a difference. Talk about pissing me off. I've got a carb on order now from a shop in Ohio that specializes in Qjets (need it for emissions inspection) and they have a couple of engine dynos with motors similar to mine and say they should be able to get it tuned "close" to what my set up needs. They are also saying that it could be I'm not getting enough fuel at idle through the carb's idle circuits which might be the problem (sounds good, but why work great for two days?)

Three month turn around though on the carb so I'm hoping to have it by the middle of march. I really need to consolodate all of my posts into one to see if it all makes sense. Anyway, I'm going to go with new plugs and a new distributor as soon as I get my tax return back as well as re-tighten all my head bolts just in case this is a crazy vacuum leak in the heads and go from there. When I get the carb on I'll post again. If anyone has any ideas what so ever, please post them.