ESC need someone that knows more about ESC system than I do

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Ricko1966

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Robyn I feel your pain and I think your best option. Now is tune it for how it runs best 90% of the time and have the ability to pull a few degrees on the other 10% . Maybe at some point you will figure out which circumstances create your ping and be able to control it better. Things to think about thermo vacuum switches,hobb switches,throttle postion switches, Different hg. advance cannisters. I don't want to confuse anyone and this and it is just one example. Say the truck only pings from 200 degrees at and up so a thermo vacuum switch that provides vacuum to a hobbs switch at temperatures 195 and above creates the ground to pull timing. That's just 1 example. Another example of something that might help,a water injection system maybe both. I did make a very crude water injection system once using a metal windshield washer squirter.i drilled a hole in the air cleaner top put the end of the squirter through the hole mounted it to the top and aimed it so it hit above the venturi hitting the side of the airhorn so the water wasn't shooting straight through the throttle plates it was hitting the wall and breaking up going in as a mist. Fed it water with a washer pump
 

Ricko1966

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It's to bad there isn't a way to get a knock sensor to trip a relay. If that were possible then it could be an automatic retard system....
I researched that once I couldn't figure out a way to do it. I wish I could.
 

SirRobyn0

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Robyn I feel your pain and I think your best option. Now is tune it for how it runs best 90% of the time and have the ability to pull a few degrees on the other 10% . Maybe at some point you will figure out which circumstances create your ping and be able to control it better. Things to think about thermo vacuum switches,hobb switches,throttle postion switches, Different hg. advance cannisters. I don't want to confuse anyone and this and it is just one example. Say the truck only pings from 200 degrees at and up so a thermo vacuum switch that provides vacuum to a hobbs switch at temperatures 195 and above creates the ground to pull timing. That's just 1 example. Another example of something that might help,a water injection system maybe both. I did make a very crude water injection system once using a metal windshield washer squirter.i drilled a hole in the air cleaner top put the end of the squirter through the hole mounted it to the top and aimed it so it hit above the venturi hitting the side of the airhorn so the water wasn't shooting straight through the throttle plates it was hitting the wall and breaking up going in as a mist. Fed it water with a washer pump
I was thinking about the water injection thing earlier.

Many years ago I built a vacuum operated "water injection" system, if you can call it that. I built it based on this old mother earth news article from 1979. >>> https://www.motherearthnews.com/diy/water-injection-system-zmaz79ndzraw/ <<< It's simple, but because there is no pump most of the moisture is induced at high vacuum. Possibly it could in enable a guy to run more vacuum advance. For example I'm pulling out of number of degree from the vacuum canister since it's adjustable to keep it from pinging. Even where it's at the engine likes to ping when in overdrive and I'm stepping on the gas it's just about to down shift and at the right speeds it'll lug and ping pretty bad for a second. Might help with that. IDK if I'd actually go though the trouble to build this but it's a cheap thing to maybe try.....

Right now I'm just a bit frustrated. I've put in my time in on this ESC thing and it's still non-functional. It's not like I was trying to do anything fancy I just wanted it to work like it is suppose to, but enough is enough, it's time to move on to another plan I guess.

I might pop the top on the carburetor (remember I'm running an edelbrock the PO installed), and go up one jet size on the secondaries, and see if that helps with WOT pinging.
 

Ricko1966

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Robyn now think about this for a minute,I tried to explain this before but maybe didn't do a good enough job. If limiting the degree of vacuum advance will stop the problem,quit try to limit the degree of vacuum advance, try to make it go away at certain vacuum levels. These are imaginary numbers to make this easy. You pull 20 hg vacuum at Idle your vacuum can is all in at 10hg use a can that's all in at 19hg so the vacuum advance goes away as soon as you give it throttle. Now those are very exaggerated numbers but I would not be surprised if that 1 size fits all can isn't all In by 7hg and your mostly stock 305 is probably over 10 90 percent of the time.. you can test this for almost free not convenient but almost free. Put a tee in the vacuum hose to the advance,run a piece of vacuum line off the tee into the cab. Put your thumb over the end of the vacuum line and go for a drive when you get ping let your thumb off so you lose vacuum to the vacuum advance. Did the ping go away?
 
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SirRobyn0

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Robyn now think about this for a minute,I tried to explain this before but maybe didn't do a good enough job. If limiting the degree of vacuum advance will stop the problem,quit try to limit the degree of vacuum advance, try to make it go away at certain vacuum levels. These are imaginary numbers to make this easy. You pull 20 hg vacuum at Idle your vacuum can is all in at 10hg use a can that's all in at 19hg so the vacuum advance goes away as soon as you give it throttle. Now those are very exaggerated numbers but I would not be surprised if that 1 size fits all can isn't all In by 7hg and your mostly stock 305 is probably over 10 90 percent of the time.. you can test this for almost free not convenient but almost free. Put a tee in the vacuum hose to the advance,run a piece of vacuum line off the tee into the cab. Put your thumb over the end of the vacuum line and go for a drive when you get ping let your thumb off so you lose vacuum to the vacuum advance. Did the ping go away?
No you communicated that just fine the first time as well as this time. The thing is when I stuffed that adjustable can in, I did it because I HAD to drive the truck 400 some odd miles and it was going to ping itself to death with the OEM can, and I had the adjustable unit on hand. So it was suppose to be "good enough" to be a quick fix to get by with for the time being. I always planned to go back to the original can when I got the ESC going. I completely understand. I wanted to put it back to factory not going though a tuning process, but the process it shall be..... Thanks for the help and advice along the way I do appreciate it.
 

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Robyn and anyone else,i found my esc unit this past weekend.it was working when removed,free to a good home.just pay shipping.
 

Ricko1966

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I'll give Robyn 1st pick but I want it. 2nd chance at it please.
 

SirRobyn0

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Robyn and anyone else,i found my esc unit this past weekend.it was working when removed,free to a good home.just pay shipping.
Thanks guys. Give me until later today - tomorrow morning at the very latest to decide. I had a thought this morning on the way to work that perhaps my connector to my ESC module is not making the best connection. After I double check that I'll let you know.
 

SirRobyn0

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Ok I'm going to be back looking at wiring diagrams. It seems like my last ESC module took something out with it as there is no power to the module. So I'm going to see what the deal is with that, but it's going to be my last attempt to bring the ESC back to life. I just can't keep putting anymore time into it.

So for that reason @Ricko1966 you have been instrumental in me getting this far with the ESC and for that I thank you. If you want @dusterdude module go for it. You well deserve it. Good luck and let me know how your own ESC system progresses.
 

SirRobyn0

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Ok so if I read this diagram correctly (diagram thanks to @AuroraGirl ) The B+ pink wire which appears to become the orange wire and has a fusible link in it seems to power the module and takes the power from the coil power wire right where it enters the distributor. I've seen that double connector there at the coil. I knew that wire had to do with the ESC but didn't really realize that it was the power source for the module.

I'll check that near the end of the day here at the shop and see if that fusible link is toast.
 

SirRobyn0

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More later tonight. I got to get on the road and I've got 2 or more hours of driving to do and it will all be with a working ESC system and the used module. I get the boob award. I forgot that I had disconnected the ESC power wire off the coil when the I pulled the last module to prevent an accidental grounding of that wire.

More later on have the drive goes.
 

SirRobyn0

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Ok the drive report.

The truck ran fine, it did not stall or faulter. I'm undecided on the function of this ESC unit as far as it's ability to pull timing. I think it's working, but not 100% sure.

I tried to do a quick tap test on the manifold, but couldn't get it to respond. Keep in mind that my knock sensor is relocated to the drivers side, so the way the air tubes are on that side it's terribly hard to get a good swing on the manifold while perching my knees on the core support leaning over holding the timing light and watching the marks.

So I've been running around with the base timing set at 0, spec is 4BTDC so I set it back to 4BTDC. I left the adjustable vacuum can on and made no adjustments to it. If it looks like the ESC is doing it's thing after I get some drive time in I'll put the stock can back on.

My experience. I was having trouble with it pinging bad, if it lugged a little in over drive. It did not do that on my drive tonight.

Without the ESC I had issues with some moderate pinging and WOT, particularly over 3K RPM. There is one good long hill on my drive tonight and I ran it hard and at high RPM and it did not ping. After that hill I had to stop at a light, when I pulled way I ran it hard and did get some pinging.

Basically my experience went like that. There were times I expected it to ping and it did not. Other times it did some mild to maybe moderate pinging. I swear I felt it pull back the timing on occasion, but! It rained like helll and we got some hail on the drive to which very much hampered my ability to hear the engine.

So I think that the proof will come the next few times I get to drive it and it's not raining like helll. So my thinking right now is the jury is still out. Not sure how much I'll be driving it this weekend so it's hard to say if there will be a report before next week or not.
 

Turbo4whl

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I must ask, what are you using to tap on the manifold? Best practice I have found, is to use a large combination wrench (3/4 to 7/8"). Hold the open end and rap quickly with the box end. This has worked well for me and you can tap the manifold much quicker than using a small ball pein.
 

SirRobyn0

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I must ask, what are you using to tap on the manifold? Best practice I have found, is to use a large combination wrench (3/4 to 7/8"). Hold the open end and rap quickly with the box end. This has worked well for me and you can tap the manifold much quicker than using a small ball pein.
I was using a large combination wrench around 7/8 or 1" or so. I believe I was not tapping fast enough. I just couldn't get it going good in that position, and needed to get driving.
 

SirRobyn0

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Hopefully, I will do only 3 more updates. This morning, tonight and then one a few months from now, assuming the system continues to work.

So my experience this morning. The ESC system was clearly working and doing what it is suppose to be doing.
There is one long hill on the way into work that I'd often get a little bit of pinging even when the ESC was not working and I was running around with the timing set 4 degrees retarded. Running up this hill with the timing set to spec, with the ESC would have resulted in massive pinging. I ran it hard today. I laid into the throttle and did not let out except to control speed. I never heard a peep of pinging, but I did feel the ESC pull timing. One time was really obvious I was pulling this particular stretch of hill and was increasing speed slightly and felt the power pull back a tiny bit. Since the truck hasn't had that behavior in the past I assume that was the ESC pulling out timing. Other scenario cruising and lugging just touch in overdrive, again no pinging. So I feel like the ESC was working this morning and I'm very happy about that.

Tonight I'll be on the road in the truck for about 2 hours. I'll report back tonight how that goes, and if it goes well hopefully I won't need to give another update for a few months.

I can already see a path though if the ESC continues to function as it should. I should be able to continue running regular gas and hopefully on my daily commute I will see a fuel mileage increase since my timing, particularly at light throttle will be more advanced. If I need to tow or haul and can put premium in it, the ESC will hopefully not need to pull timing or will pull less timing and therefore I'll see an increase in power. And even if I've still got tanks full of regular at least it shouldn't ping. Cool very happy so far!
 

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