So I took everyone's advice and pulled the carb so I could clean out the EGR passages. I took a 3/8" bit and drilled all the carbon out of the two bungs in the intake manifold, which I assume are the EGR passages. I still get knock at low RPM and moderate throttle. At WOT the knock goes away. Right now I'm at a base of 12 degrees timing. This is an Olds 307 BTW.

You have to make sure that you got all the way to the bottom, mine were so hard it took a little bit of pressure with the drill to get it to punch through. It will go down around 1/2 to 3/4" past the bottom of the EGR tubes length were you can see. Just judge that you did go to the bottom. You might even feel it hit the manifold floor (drill not running!)

Make sure the EGR is functional, when the EGR valve isn't hot (it is in the exhaust stream it gets HOT), start car and squeeze the valve, it should kill the engine or at least make it run VERY rough.

Did you blow out the passege from the EGR valve to the tube extensions? You don't want all those carbon chunks going through the combustion chamber when you drive it (not that it matters now....)

It is a positive backpressure EGR valve, so you can't test it with a vacuum pump with the engine off, it has to be running with enough backpressure (engine revved up to 1500 rpm or so) to close the orifice valve in the EGR valve to allow it to open.

I did find a std EGR valve that isn't a backpressure type from my old 1976 Olds Delta 88 350. All EGR's in 76 for Olds V8's were non backpressure type, the backpressure transducer was external and only for California cars. This provided proper EGR operation for my 85 Cutlass when I put on a cat back exhaust that reduced backpressure significantly.

isnt the timing supposed to be at like 20 or 22 degrees or something. i cant remember off the top of my head

No, most engines enjoy an initial timing of somewhere around 10 degrees, give or take. Perhaps you're thinking of either vacuum advance or mechanical advance.

Brian

I actually unscrewed one of the bungs in the manifold and cleaned it out while it was off of the motor with some carb cleaner and a toothbrush. The other, larger tube, I didn't have a socket for, so I did it while on the car. It wasn't too gunked up, so I just sprayed it with carb cleaner and ran the drill until I hit manifold bottom (or the lifter valley, not sure how these Olds motors work). It took out some gunk, but it really wasn't as bad as I was expecting.

I also cleaned out the whole carb and all vacuum runs on it with cleaner and put in a new gasket. What the hell is that Hard line that runs from the choke to the intake manifold on the passenger side? When I was screwing that back on it just kinda, came out of the manifold. I don't think it was too securely in there.

I ran the engine idle and squeezed the EGR, it definitely stalled. The EGR seemed a little crunky and took more force than I would have expected to open though. You know how many in. lbs it takes to actuate the EGR? I have a pump that'll grab up to 30 in. lbs, so I can hook it to the line and try. If the EGR wasn't opening correctly, I'd get knock?

Base timing on the Olds 307 is 20 degrees at 1100rpm per the VECI label under my hood. If I run 20 degrees right now, it's just knock city. At least at 12 degrees, I don't start to knock until I'm real easy on the throttle and I shift into 3rd gear.

I thought it was 10 also, but mine ran ok with 93 octane and higher, but I don't remember. The 350 wanted much more timing, the 307 was making good power with stock to stock + a couple degrees.

I later installed a 350 Olds and a later a larger cam. Stay with the factory Olds cam or the 85-87 442 cam at most (depends on what year your 307 is, roller or not), or something Moneydello has that is small like around 194/204 duration and around .440 lift. I had the 204/214 SSI cam (from PAW). It ran ok, but lacked some bottom end, wasn't bad, but I knew the Olds 350 had more with the factory 1977 cam, ECM was fine with 350 and larger cam. I only replaced the cam out of a distibutor gear failure due to timing chain being loose and cam walking in the block.

Man am I getting off topic or what????

Yes, I miss my Olds 350..... It ran good, very good....

I'm sticking with stock swirl heads and the stock roller cam because I really don't care. This thing is my beater, so it doesn't have to go fast, it just has to get me to work and keep me cold in the hot Florida sun. I just don't like it knocking, it's embarassing when people are trying to check out my cool ride and it sounds like a diesel :)

I've got the Chevy 383 running the 240/246 .575"/.599" cam for the fun car anyway :D

I actually unscrewed one of the bungs in the manifold and cleaned it out while it was off of the motor with some carb cleaner and a toothbrush. The other, larger tube, I didn't have a socket for, so I did it while on the car. It wasn't too gunked up, so I just sprayed it with carb cleaner and ran the drill until I hit manifold bottom (or the lifter valley, not sure how these Olds motors work). It took out some gunk, but it really wasn't as bad as I was expecting.

I also cleaned out the whole carb and all vacuum runs on it with cleaner and put in a new gasket. What the hell is that Hard line that runs from the choke to the intake manifold on the passenger side? When I was screwing that back on it just kinda, came out of the manifold. I don't think it was too securely in there.

I ran the engine idle and squeezed the EGR, it definitely stalled. The EGR seemed a little crunky and took more force than I would have expected to open though. You know how many in. lbs it takes to actuate the EGR? I have a pump that'll grab up to 30 in. lbs, so I can hook it to the line and try. If the EGR wasn't opening correctly, I'd get knock?

Base timing on the Olds 307 is 20 degrees at 1100rpm per the VECI label under my hood. If I run 20 degrees right now, it's just knock city. At least at 12 degrees, I don't start to knock until I'm real easy on the throttle and I shift into 3rd gear.

Becareful removing them. 1. They can fall in the engine, that sucks. 2. They can rip the threads out of the intake if it is old and getting soft there. I did mine, but the intake was off the car first. I put brass plugs in and drilled a 3/8" hole in each. Ran fine.

Make sure you are setting it with the jumper in the ALDL to put it in timing set mode. Else it will be wayyyyy off.

The EGR might be a little stiff, but not hard.

That tube is the choke tube, without it the choke will not open properly, likely much slower than it should open. There is a calibrated vacuum leak in the choke housing and it draws air from the air cleaner through those tubes in the intake to warm the air and that air passes across the choke element warming it and opening it up faster. Just press the tubes back in the intake, no big deal. They seal up enough. If you have to bend them a little that is fine.

I tried to convert my E4MC carb to an E4ME (electric choke), but it always opened too fast and caused cold weather drivablility problems. Stay with the hot air choke, it does work best...

Make sure the EFE valve isn't stuck closed, it will ping like mad then. It will superheat the intake's exhaust crossover.

After around 2-3 minutes ensure the valve moved to the open position (it is on the driver's side exhaust manifold). Often with old age the return spring breaks or fatigues and it eventually rusts up enough to start sticking. The 307 likes it when it is bitter cold out, but it will be fine no matter what. You can plug the vacuum line and then if needed, hardwire the valve open.

Becareful removing them. 1. They can fall in the engine, that sucks. 2. They can rip the threads out of the intake if it is old and getting soft there. I did mine, but the intake was off the car first. I put brass plugs in and drilled a 3/8" hole in each. Ran fine.

Make sure you are setting it with the jumper in the ALDL to put it in timing set mode. Else it will be wayyyyy off.

The EGR might be a little stiff, but not hard.

That tube is the choke tube, without it the choke will not open properly, likely much slower than it should open. There is a calibrated vacuum leak in the choke housing and it draws air from the air cleaner through those tubes in the intake to warm the air and that air passes across the choke element warming it and opening it up faster. Just press the tubes back in the intake, no big deal. They seal up enough. If you have to bend them a little that is fine.

I tried to convert my E4MC carb to an E4ME (electric choke), but it always opened too fast and caused cold weather drivablility problems. Stay with the hot air choke, it does work best...

Seems like I did okay. They one I took out went back in without taking any threads hostage.

I had my Actron GM diag tool plugged in (someone gave it to me, I didn't buy it), which if I'm not mistaken, grounds out the correct pin. Right?

The EGR actually felt crusty and didn't push evenly. Kinda like a door hinge that needs oil. I bet it's wasted, but I'll run a vacuum pump on it tomorrow to see if it moves at all.

Good, cause when it popped out in my hand I said all sorts of expletives. I just shoved it back into the intake and hoped for the best. Actually, now that I think about it, it was the one that ran to the back of the carb and joined with that little flimsy 1" piece of hose. It runs into the same plate on the intake as the choke one. Are we still okay?

I don't plan on doing any conversions to this car whatsoever. It does its intended purpose, which is to cruise low, long, and comfortable, just fine. If anything, I'd replace that Q-Jet with an Edelbrock replica, but that's only if that Q-Jet totally blows up on me.

Make sure the EFE valve isn't stuck closed, it will ping like mad then. It will superheat the intake's exhaust crossover.

After around 2-3 minutes ensure the valve moved to the open position (it is on the driver's side exhaust manifold). Often with old age the return spring breaks or fatigues and it eventually rusts up enough to start sticking. The 307 likes it when it is bitter cold out, but it will be fine no matter what. You can plug the vacuum line and then if needed, hardwire the valve open.

EFE valve? All of this new engine technology is confusing me now. Is it something that I can just replace? I'm telling you, this thing is a knock monster, but it doesn't knock all the time, so I'm 99% sure it's not a bearing :)

Early Fuel Evaporation.

Based on a thermal vacuum valve or the ECM (forget which on that car) when coolant temp is below around 50-70 degrees C the valve closes and all the exhaust gas from the drivers side exhaust manifold though the intake manifold to get to the other side so all the gasses exit the passenger side manifold. This is only on for a short time, enough to get the intake warm quickly.

Just wire it open, to replace it you have to remove the exhaust crossover under the car, and then you risk breaking exhaust bolts. It isn't that important. It helps warm up the engine faster so when the choke is fully open (within 3.5 minutes max). You can check, if I remember right the vacuum line is metal, and comes up the back of the engine between the engine and the master cyl area. I think it goes to the vacuum switch box, you know, the little black box on the back drivers side of the intake. It is nothing more than a vacuum switch that the computer can control so you don't need more temp vacuum switches.

Knocking is death to an engine, don't let it do it. It hammers the tops of the rod bearings HARD. And it will break ring lands, melt pistons, burn valves, etc.

Please don't let it!

Make sure thermostat isn't stuck closed either, that will make it ping too...

Yeah, I just read about it in the service manual. Talk about useless! I'm wire that baby open tomorrow when I get home from work even if it isn't broke. Come to think of it, the car kinda behaves how an old car I had behaved when it had a cat converter clogged, 'cept the Caddy only does it warm. That would make perfect sense if that little valve deal in the exhaust was stuck closed. Also explains why the car has more power when it's cold vs. when it's hot.

I tell ya though, a new carb gasket, a clean carb, and clean EGR passages definietly gave the car some pep.

I definitely won't let it knock. I'm unhappy unless the car I'm driving is in perfect running order.

On a side note, my hood ornament came in the mail today. The hood looks a thousand times nicer with the wreath and crown on it like it's supposed to.

Yeah, I just read about it in the service manual. Talk about useless! I'm wire that baby open tomorrow when I get home from work even if it isn't broke. Come to think of it, the car kinda behaves how an old car I had behaved when it had a cat converter clogged, 'cept the Caddy only does it warm. That would make perfect sense if that little valve deal in the exhaust was stuck closed. Also explains why the car has more power when it's cold vs. when it's hot.

I tell ya though, a new carb gasket, a clean carb, and clean EGR passages definietly gave the car some pep.

I can say from experience that my Olds 307 sure perked up when I got the EGR system working right. With 186000 miles running 87 octane not a single ping!!

The cars would have awesome power when cold, but they "screwup" the calibration to get the car info warmup ASAP and then worry about emisisons.

That is the symptom fo r it....

Well, I guess the majority of my knocking yesterday was due to the carb cleaner being in the intake manifold. I started 'er this morning to go to work, it was missing like crazy, so I drove her down the block. Half way down the block, after spy hunter smoke screening the neighbors, it came back to life. It barely knocked today on the way to work, only around 50mph when in OD and barely on the gas, and the acceleration was MUCH better than before.

I still think you guys might be onto something with that EFE thing. The exhaust on the driver's side just doesn't sound... right. Either way, I think it's a bad idea, so I'm going to disable it.

I'm also going to check the EGR with a vaccuum pump. I guess if that thing was a little crunky it would cause some minor knocking. If I take the EGR off in order to replace it, should I spray some sea foam and maybe some compressed air down in the EGR passages? Could I jam a rifle cleaner down in there to get the carbon out?

i would try to pull the carbon out, not jam it in. because then it is free to go other places in the engine.

i would try to pull the carbon out, not jam it in. because then it is free to go other places in the engine.

Hmmm, I dunno how I'd manage to pull it out. If it's coated in carb cleaner and broken up, it should shoot right out the exhaust ports during the first couple of strokes. I'm hoping the majority'll come out on my rifle cleaner :)

Well, I guess the majority of my knocking yesterday was due to the carb cleaner being in the intake manifold. I started 'er this morning to go to work, it was missing like crazy, so I drove her down the block. Half way down the block, after spy hunter smoke screening the neighbors, it came back to life. It barely knocked today on the way to work, only around 50mph when in OD and barely on the gas, and the acceleration was MUCH better than before.

I still think you guys might be onto something with that EFE thing. The exhaust on the driver's side just doesn't sound... right. Either way, I think it's a bad idea, so I'm going to disable it.

I'm also going to check the EGR with a vaccuum pump. I guess if that thing was a little crunky it would cause some minor knocking. If I take the EGR off in order to replace it, should I spray some sea foam and maybe some compressed air down in the EGR passages? Could I jam a rifle cleaner down in there to get the carbon out?

Remember, the EGR will not work if the engine isn't making enough backpressure to close the backpressure valve inside of it, which causes an internal vacuum leak to the EGR passage. It is normal, and calibrated for it.

Best bet is to remove the EGR valve and use a shop vac to blow out the passages from the carb to the open EGR holes. Use a piano wire or something to follow the passages all the way through.

I gotcha, so run the air from underneath the carb and blow it out of the EGR mounting area. Damnit, that means taking the carb off again :)

yup... Bummer....

Remember, torque carb to factory specs, like around 10 ft/lbs!! Frequent removal and install can get it over torqued and crush it. Seen it on mine! I don't know who, if me, my dad or a mechanic, but I want to slap em! Had to replace the carb! It crushed my TPS to where it would not adj.

Alright, so here's what I got. The EFE was dirty nasty, so I just disconnected the linkage and moved it to open, which I beleive is what it is when the rod is fully extended. Now that's not an issue, but I still get knock.

I tested the vacuum lines, I get roughly 17 in. lbs both directly from the carb and from the line that connects to the top of the EGR when holding the throttle steady. Now, when I plug this line that has verified to get 17 in. lbs into the EGR and move the throttle, I don't feel the valve move at all with my fingers. I also pulled the line and ran it to the new EGR, even though it wasn't bolted down. It also doesn't move, so now I'm clueless. Someone help!

Have you changed the backpressure of the exhaust? It will have an adverse effect on EGR opening. That is why on mine I swapped to the ported EGR valve off of a 1976 Olds 350 from a Delta 88. Verify that it will bolt on before you buy it. Mine did, but I also had an 1982 307 intake on my 77 350 Olds. But the to untrained eye, you could never tell it wasn't a 307....

The ported worked pretty well for me. The backpressure EGR's are touchy on backpressure. Almost all carlines switched to positive backpressure by 1980. I don't think the negative BP type was sensitive enough.

Well, I think the major problem was carburetion guys. I took the old Q-Jet off, rebuilt it, replaced the TPS, and threw it back on with base settings. Immediately, I noticed a huge increase in power and no more knock. I took the timing back up to 20 degrees and managed to run it at extremely low RPM with the AC and no knock. Right now I have a tank of 93 octane in there now, just because I didn't want it to knock itself to death, so I'll see how it does with 87 next time I fill up.

I haven't adjusted any of the fuel mixture settings from dead up stock yet either. Maybe if I get bored I'll break out the old dwell meter and set it properly. I could also use an idle adjustment, but I'm out of vacuum hose and I'm too lazy to go to the store to get a piece :D

Just figured you guys might want an update.

Oh, and with the motor at 20 degrees like it's supposed to be instead of the 12 I was running, that little 307 hauls ass! I had that 4500lb boat doing 60mph in no time!