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Thanks for the idea, but for the time being I've given up on that port and instead I'm trying to get the car to run properly. If I'm correct, that port is just for emissions and shouldn't affect how the car runs. I did get some more of the plug out with some curved chisels I cut from aluminum plates, but it's still filled for the most part.
Right now I'm having problems with the car idling smoothly. It revs up and down and when it goes down, it sounds like it's about to die. If you keep your foot on the pedal it runs fine, it just won't idle. Spark is good and it ran fine before I swapped stuff so I'm thinking it's carburator or emissions related. I did manage to mount the other TPS on the carb, so now the ECU at least knows something. I've messed with mixture and idle speed with no luck. Any ideas?
EDIT: Did some more research on the idle problem and it sounds like clogged egr ports can cause problems. Yes I know that it's not an egr port, but perhaps since it related to emissions it could be causing something.... I'm honestly not sure, but if I can't the car running right I'll probably take another crack at it. I think the only method left to try is heat. How likely is it that the center iron will warp with that kind of heat?
Last edited by Benjamin4456; 02-11-18 at 10:41 AM.
Well shoot. That stuff is really down in there and is hard as rock. When I could get to it, even a chissel and a hammer had a tough time with it. A drill worked ok but there's no way to get one down that far. Any other ideas?
Edit: I once read an electrical blog where a guy took wire from a coat hanger, sharpened one end and used it like a small flexible drill bit. That might be a tedious but low risk way to chew it up/weaken it. Multiple holes, then back to the hammer.
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One forum said that isopropyl alcohol would, over time, soften the JB. I can't confirm or deny, but you could pour a bunch in there and let it steep. Maybe do a test on some scraps you've already removed.
Soaking heat is not a good option for the reason's KC mentioned... coolant above 200°F is a worry and the fail temp according to the JB FAQ is 600°F for the standard stuff. Also, I guess there's an "Extreme Heat" version of JB that is grey when cured and theoretically withstands 2400°F. Who knows what's in your port.
Again, cool ideas and thanks for the determination on getting this fixed. Ironically I've already tried something similar to the coat hanger idea. I have some finding wires (like the kind for drilling through floors and stuff), but all it did was fly around so... Good thought though, and maybe since a coat hanger is a heavier metal it would work better. As for the alcohol, well... I've tried acetone but I've gotten enough of the plug out that it just slowly leaks into the engine so I can't really soak it and let it sit. I think a right angle chisel might be my only option left. I'll probably stop by home Depot later today and see if they have a chisel that will work.
Maybe not dry ice, but I've heard of some people having success with canned air (like electronics cleaner). It's apparently cold enough to do something to the jb weld. If the chisels don't work, I'll give that a try.
EDIT: Is it remotely possible that the partially opened avc port would cause an uncorrectable rough engine idle? It's the only thing that has changed since I last ran the car and now it won't idle well. By partially open I mean barely open. Just wondering.
Last edited by Benjamin4456; 02-12-18 at 04:11 PM.
Finally got the plug out of that port. I spent about three hours strait just on the port this weekend. I ended up just using a bunch of bent nails (I'll post a picture later), and a cheap chisel from Harbor Freight. The plug went down into the port about 3-4 inches so getting it all out of that little opening was no small job. The majority of the plug came out with some slow chipping but near the end, I knocked it loose and it fell down the port. The shop vac fixed that by sucking it back up the top where I then put a right-angle nail in underneath it so it couldn't fall down again, and then proceeded to break it up with another nail. When it all done I fed a finding wire down to make sure it was clear and it was so... back together it went. While I had the carb off I re-soldered the wires for the ECU temp sensor (which had fallen off), so now the auto choke works again. The car runs, but only with throttle and above 1500 rpm. Anything below 1500 rpm something switches and the car just dies. I've got a feeling the emissions system is messing with it because the TPS closes around there, not being adjusted yet. I ran out of time before it started to snow so I haven't done anything except for start it up that once. Once the weather clears up, I'll try to figure out what's up with the idle.
I want to make sure I understand what you have. You have a 1979/1980 engine and using a 1981-1985 intake/carb? What year emission and ECU, if any, are you running?
Yeah it's a bit Frankensteined. When I got the car it had the 81-85 engine, with the exhaust, intake, everything, including the ECU, from a 79-80 car. When I swapped the intake, exhaust, carb, and emission solenoid rack to the 81-85 system, I also took the TPS from the previous year carb so that the ECU would still understand the signal. As for the emissions rack, the only stuff that matches up is the vacuum advance and the relief solenoid. I blocked and plugged the shutter valve, and the switching valve is hooked up but the early year ECU's don't have a wire for it.
So just to clarify:
Intake, exhaust, engine, carb, air box, emissions rack (81-85.
ECU, TPS, wire harness (79-80)
All vacuum lines are connected except for the vacuum advance (plugged because one actuator on the distributor is kaput) and the shutter solenoid. The switching valve is hooked up but there is no electrical connector for it.
Hope that helps, if something is confusing or missing just let me know and I'll update it.
Small update:
It stopped raining for a little so I had enough time to do some tuning. The car now idles at 750ish rpm but I had to richen the mixture quite a bit. The mixture screw is probably 5-7 turns from closed. The car definitely smells rich, but no smoke. If I turn the mixture screw clockwise more than where it's at now, it starts hunting and then dies. As of now I don't think there are any vacuum leaks, so would something emissions related be causing the overly rich mixture? Thoughts? I wouldn't care too much about the slightly rich AF ratio but I've got to pass smog. Its begun to snow again, so the next time I'll be able to work on it will probably be later this week.
You may need to get an FB ECU to make this all work. I assume the FB exhaust has cats? The other option is to understand what the sniff for and get some tools measure it or access to tools and tune until it passes.
Oddly enough I have the entire wire harness, ECU included, from my FB parts car. I was trying to avoid swapping them since the whole harness is different, and that would require the dash to be removed, tail-lights modified, etc. I might still do it this summer but I was trying to keep the SA more or less an SA except for the engine where I didn't have an option. What part of the emissions system would be most affecting the idle mixture? Since the SA ECU and system is a bit simpler than the FB, I had thought I could make a "stand alone" just for the emissions from an Arduino or something. I would keep the original ECU and keep the sensors wired to it so that other stuff will still work, but the solenoids would be controlled by the Arduino using the og ECU for input. I would need to do some research to find all the operating conditions but if I can't just manually control the switching valve, it might worth a shot.
This is my current emissions set up:
Vacuum Advance: In the name. Harness present. (normally open or closed?)
Relief Valve: Switches air from air pump to air box when rpm exceeds about 1000 rpm (dependant on TPS). Harness present.
No AC installed
Shutter Valve: Closes rear rotor primary intake port durring decel to prevent backfiring (not nesisarily needed and at the moment is disconnected) no harness plug.
Switching Valve: Directs air from air pump to either ACV port on engine (port air) or CAT air line (split air). (Conditions?) No harness plug.
Snow let up again so I may be able to do some work today.
Edit: One other odd thing. If you mash the gas from idle, it bogs badly. The accelerator pump works but may be miss-adjusted. Anything else that would cause this? I haven't messed with the AP much yet so that's probably what it is but just in case.
Last edited by Benjamin4456; 02-21-18 at 10:46 AM.
I'm not sure you can make the 1981/1985 rats nest (which have variation themselves) work with the 1979-1980 ECU and wiring. The 1979 has 3 to 4 square vacuum pots. One is on the carb and then there are 2/3 on the rats nest depending if it was cali equipped.
I'd be more inclined to swap to the 1985 engine harness/ecu and then work out what would be needed to make the 1980/1979 dash work (idiot lights and gauges)
Last edited by KansasCityREPU; 02-21-18 at 01:29 PM.
As for the 81-85 rats nest I know what you mean, I've got at least three variations in my parts bin. My SA carb had two solenoids on it (vent, and decel), and three on the rack (advance, relief, and AC). The main reason I think combining the two systems will work, at least for now, is because this variation FB rack has only one vacuum advance solenoid as opposed to two like most others I've seen. The SA system used a line from the carb to adjust (leading or trailing, I forget which), and the other from the solenoid. The newer rack has both on the one solenoid and as I have one connector for it (as long as opp conditions are the same), it should work. The only other emissions differences is the shutter valve (not necessary), and the switching valve which could be rigged up for manual operation pretty easily. The carb I'm using doesn't have a power/richer solenoid and I've swapped the TPS so the signal matches the ECU. In other words, nothing on the carb is left unplugged. All I need to figure out now is if the ACV is even working and if it is, where is it sending air. If it's going to the wrong place maybe it'll fix the rich idle problem. If there's nothing wrong, I'll start messing with the other emissions stuff. Maybe this summer I'll swap the harness, but for now I'm just looking to get the car smogged and registered. I'll update if I discover anything new.
Did some testing last night and it appears the ACV is not working at all. Basically I jumped the vacuum lines for emissions stuff across the solenoids so they couldn't be a factor. No matter what I did, air always came out of the relief air hose. I'm guessing it's just locked up after not being used for so long, but when I go through it tonight I'll also check on the vacuum passages to make sure they're not clogged. What's the best way to break the valves loose if they are stuck? Sure hoping it's not a diagram that's bad.
Well darn... The relief valve diaphragm is shot. They were both frozen but only the diaphragm on the relief valve is bad, although I did get both moving freely. Unfortunately, that valve is needed otherwise air will never get past it and to the switching valve. Any ideas on where to get one?
EDIT: Just had a thought. Would it be plausible to try and seal it up? Maybe silicone or something else? Probably not a good idea but maybe worth a shot?
Last edited by Benjamin4456; 02-23-18 at 07:05 PM.
So using silicone on the valve seems to have worked. I let it cure overnight and I installed it this morning. It does the job ok, although air still comes out the relief valve when it's activated, but it's notably less air than when it's off.
Now I'm having issues with the idle dropping after you let off the gas and then slowly coming back up to where it's supposed to be. Sometimes it's enough of a drop to kill the engine. To be clear, I was having the idle issues before, now it's just higher on the priorities list. Ideas?
Edit: The idle usually only drops if the engine was brought above 2500 rpm. If the engine was around 3000-4000 or higher, the engine idle drops and stays low while also running rough and typically dying. What's odd is that if the car starts running low and rough (after decelerating), simply shutting it off and starting if back up fixes the problem. It even starts without a hitch. I'm just having trouble figuring out what could be causing this. I'm open to any ideas, even the outlandish ones.
Last edited by Benjamin4456; 02-24-18 at 09:31 PM.
New developments.
1. There was a t-fitting in the vacuum system that had broken (now replaced)
2. Float levels are a bit high (not fixed yet)
3. The check ball in the accelerator pump outlet may be missing (not sure yet)
Tonight I'm going to go through the carb with a fine tooth comb. Everything is coming apart and will be cleaned careful. The last time I took the carb completely apart was in the summer when I took it off the parts car.
Here the odd thing, the car would idle just fine once it's warmed up but if you touch the throttle (either floor it for a second or go above 2500 rpm), the car no longer idles. Turning off the engine and restarting it fixes the problem completely. Is there something vacuum related that could be getting stuck?
02-11-18, 10:10 AM
