Knock Retard
- Thread starter dgoodhue
- Start date
BigAl...
Member
Re: Knock Retard
Dave, It's actually easier to just buy the entire distributor, I paid $99 for a new dist at autozone. It made a huge difference on my rpm signal, it went from a saw blade to a nice smooth line. Also if you haven't changed the coil I would consider that also. since you've changed the knock sensor I would consider reinstalling it in its original location. If you don't have any rattling parts the original location is best!
I would run not walk and pickup a new distributor.
BigAl...
Dave, It's actually easier to just buy the entire distributor, I paid $99 for a new dist at autozone. It made a huge difference on my rpm signal, it went from a saw blade to a nice smooth line. Also if you haven't changed the coil I would consider that also. since you've changed the knock sensor I would consider reinstalling it in its original location. If you don't have any rattling parts the original location is best!
I would run not walk and pickup a new distributor.
BigAl...
dgoodhue
BuSTeD 4.3
Re: Knock Retard
I have all the parts to rebuild the distributor except for the pickup coil, so I will pick one of those up at lunch.
Coil is new. The knock sensor isn't exactly the easiest thing to change. I have already verified the stock one works, so maybe I will hook it back up vs the relocated.
I have all the parts to rebuild the distributor except for the pickup coil, so I will pick one of those up at lunch.
Coil is new. The knock sensor isn't exactly the easiest thing to change. I have already verified the stock one works, so maybe I will hook it back up vs the relocated.
VermontTy
Support Our Troops
Re: Knock Retard
Dave,
Mine was very corroded and rusty on the top of the reluctor, underneath where the rotor is. The shaft was splined on top as well, and I was unable to separate the two. Yes, it does have a pin to punch out on the gear like a SBC. If it will not come apart, an entire distributor at Adance Auto Parts, incuding a new module, pickup coil and distributor gear was $100 with a $170 core charge.
EDIT
Dave,
Mine was very corroded and rusty on the top of the reluctor, underneath where the rotor is. The shaft was splined on top as well, and I was unable to separate the two. Yes, it does have a pin to punch out on the gear like a SBC. If it will not come apart, an entire distributor at Adance Auto Parts, incuding a new module, pickup coil and distributor gear was $100 with a $170 core charge.
EDIT
dang it...just read this; sorry for the double post.BigAl... said:
Last edited:
SeattleSy#1255
Category 5 Conservative
Re: Knock Retard
I agree, replace the whole thing...i noticed a major difference in my choppy RPM ling, but no change in knock to my sadness. Just one of the 25 things i'v replaced trying to rid the truck of it.
BigAl... said:
I agree, replace the whole thing...i noticed a major difference in my choppy RPM ling, but no change in knock to my sadness. Just one of the 25 things i'v replaced trying to rid the truck of it.
Re: Knock Retard
hello just throwing an idea out that i found on my typhoon the other day. the serpentine belt had worn enough to let the tensioner bottom out making knocking sound . i found this kinda on accindent heard strange tap sound at drive thru. when i got home popped the hood and could feel top of tensioner ( popping) . i then slowly raised rpm and audible knocking sound out of tensioner. so installed new belt no more noise. i am sure this was causing some knock retard. truck seems to run a little better (probably in my mind though). just something to check.
hello just throwing an idea out that i found on my typhoon the other day. the serpentine belt had worn enough to let the tensioner bottom out making knocking sound . i found this kinda on accindent heard strange tap sound at drive thru. when i got home popped the hood and could feel top of tensioner ( popping) . i then slowly raised rpm and audible knocking sound out of tensioner. so installed new belt no more noise. i am sure this was causing some knock retard. truck seems to run a little better (probably in my mind though). just something to check.
dgoodhue
BuSTeD 4.3
Re: Knock Retard
I rebuilt my distributor last night, I installed it but was off by a tooth. I thought it was straight back, but when I went put it back it in seem like my option were a little to the left or a little to the right. I picked the wrong one. I can't quite get my timing back to zero (wire length)
So I will be doing that again... :rant: I hate doing distributors in these trucks. I was pretty tired, I didn't get around to looking at the plugs.
I rebuilt my distributor last night, I installed it but was off by a tooth. I thought it was straight back, but when I went put it back it in seem like my option were a little to the left or a little to the right. I picked the wrong one. I can't quite get my timing back to zero (wire length)
So I will be doing that again... :rant: I hate doing distributors in these trucks. I was pretty tired, I didn't get around to looking at the plugs.
VermontTy
Support Our Troops
Re: Knock Retard
Sounds like the can of worms I battled with a couple weeks back! Did everything come apart alright? Something I noticed as well when comparing the reman unit at Autozone to mine, when I'd rotate mine, you could feel where the pickup magnets would be lined up to the reluctor points; you could feel the resistance as the point passed by the pickup. On the reman unit, spinning it the same way had a MUCH stronger feeling as the points lined up with the pickup. Kind of tough to describe, but it seemed like the holding power of the magnet / reluctor point alignment was much stronger on the reman unit than on mine, where I could basically spin it several revolutions by hand before the magnetics would eventually stop it. This might have a lot to do with how you fellas said you waveforms had a nice crisp look to it after a new dist.
How did you check that too, Al? Oscilloscope or something?
Sounds like the can of worms I battled with a couple weeks back! Did everything come apart alright? Something I noticed as well when comparing the reman unit at Autozone to mine, when I'd rotate mine, you could feel where the pickup magnets would be lined up to the reluctor points; you could feel the resistance as the point passed by the pickup. On the reman unit, spinning it the same way had a MUCH stronger feeling as the points lined up with the pickup. Kind of tough to describe, but it seemed like the holding power of the magnet / reluctor point alignment was much stronger on the reman unit than on mine, where I could basically spin it several revolutions by hand before the magnetics would eventually stop it. This might have a lot to do with how you fellas said you waveforms had a nice crisp look to it after a new dist.
How did you check that too, Al? Oscilloscope or something?
dgoodhue
BuSTeD 4.3
Re: Knock Retard
My distributor cam apart fine. No problems what so ever, that was the easy part vs the R&R. I cleaned up all the rust on the part with the magnet attached to the shaft. I didn't spin or notice the resitance of the unrebuilt part but after rebuilding it I did notice the attraction of the magnet and the points.
VermontTy said:
My distributor cam apart fine. No problems what so ever, that was the easy part vs the R&R. I cleaned up all the rust on the part with the magnet attached to the shaft. I didn't spin or notice the resitance of the unrebuilt part but after rebuilding it I did notice the attraction of the magnet and the points.
Maxtor
New member
Re: Knock Retard
Dave -
I may have missed it, but some other non-tune related things to try: motor mounts, exhaust hitting where it exits under the cab, TC bolts, engine tie down (if you have one), and all ground wires. I am surprised that taking that much timing out didn't help, it definitely appears as if it is something other than tune related. BTW, I assume you have the stock O2, what mV does it register at WOT?
Dave -
I may have missed it, but some other non-tune related things to try: motor mounts, exhaust hitting where it exits under the cab, TC bolts, engine tie down (if you have one), and all ground wires. I am surprised that taking that much timing out didn't help, it definitely appears as if it is something other than tune related. BTW, I assume you have the stock O2, what mV does it register at WOT?
dgoodhue
BuSTeD 4.3
Re: Knock Retard
I tested the rebuilt distirbutor last night and I sanded down the passenger head ground, the only other difference is that I using the stock ignition as oposed to the MSD. I still get the same results.
In a 0-60 run Basically my knock retard graph looks like 10-12 degrees with a sharp peak of 14- 16 degrees at the end. I am actually not seeing those exact saprk retard number as I have retarded the timing 6 degrees so I have more headroom against knock.
The only thing that I haven't done is sand down the ground from drivers head to the firewall to make sure its good. Unless someone has any other ideas, basically my next step is to attempt fix this, is to pull the cylinder heads off my motor and check the cam timing to see what the issue is. Pulling that stuff a part bring up the next question, do I attempt a Vortec conversion or do I rebuild and use the L35's that I already have.
In the meantime, the only other thing I can do it hook up my alky, WBO2 and retard my timing until it goes away.
I tested the rebuilt distirbutor last night and I sanded down the passenger head ground, the only other difference is that I using the stock ignition as oposed to the MSD. I still get the same results.
In a 0-60 run Basically my knock retard graph looks like 10-12 degrees with a sharp peak of 14- 16 degrees at the end. I am actually not seeing those exact saprk retard number as I have retarded the timing 6 degrees so I have more headroom against knock.
The only thing that I haven't done is sand down the ground from drivers head to the firewall to make sure its good. Unless someone has any other ideas, basically my next step is to attempt fix this, is to pull the cylinder heads off my motor and check the cam timing to see what the issue is. Pulling that stuff a part bring up the next question, do I attempt a Vortec conversion or do I rebuild and use the L35's that I already have.
In the meantime, the only other thing I can do it hook up my alky, WBO2 and retard my timing until it goes away.
mrweelr
New member
Re: Knock Retard
Wow, you've really tried just about everything...sounds a lot like my truck, except the KR wasn't quite that high. I did everything you did and more...SOB would still knock. However, when I would run a 91/Xylene mix or spray alky, the KR would come way down. 100 octane unleaded also helped a lot with the KR. I replaced my dist. with a MSD pro-billet after giving up with the stock stuff. Truck hasn't run in over a year, but I've done so many mods now, I'm hoping the KR is gone. Went to a 60-1 turbo, ATR headers, RPM A2A, Razor alky, 50# Ultimate & injectors, solid mounts, RPM tranny, 2800TC, and a whole lot of other crap I can't think of. I'm hoping the shitty stock wastegate was the source of the problem (poor boost control and spikes). With the ITS minigate and SBCid boost controller, boost should be rock solid now. If it still knocks, I'll be upgrading to Vortec heads next. I plan on running 91/Xylene + alky from now on anyway, just for insurance, but it'll be interesting to see if the knock behavior changed with all of the upgrades. Headers just got back from being cryo'd, getting them thermal-coated this week and then it's reassembly time.
FWIW, I ran a huge braided ground strap from the back of the alternator to the frame and also cleaned the grounds at the back of the heads like you did. I changed the fuel filter as well, for good measure - I'm assuming your FP is rising correctly with boost? Upgrading the MEMCAL to #16164174 didn't make any difference with regard to knock, and swapping knock sensors twice didn't help either.
The KR is a PITA with these trucks, I have a feeling I'll have to go to Vortecs to get rid of it completely. Will keep an eye on this post and also let you know if any of my upgrades helped; motor is 70K original stock, unopened, and still running strong.
Wow, you've really tried just about everything...sounds a lot like my truck, except the KR wasn't quite that high. I did everything you did and more...SOB would still knock. However, when I would run a 91/Xylene mix or spray alky, the KR would come way down. 100 octane unleaded also helped a lot with the KR. I replaced my dist. with a MSD pro-billet after giving up with the stock stuff. Truck hasn't run in over a year, but I've done so many mods now, I'm hoping the KR is gone. Went to a 60-1 turbo, ATR headers, RPM A2A, Razor alky, 50# Ultimate & injectors, solid mounts, RPM tranny, 2800TC, and a whole lot of other crap I can't think of. I'm hoping the shitty stock wastegate was the source of the problem (poor boost control and spikes). With the ITS minigate and SBCid boost controller, boost should be rock solid now. If it still knocks, I'll be upgrading to Vortec heads next. I plan on running 91/Xylene + alky from now on anyway, just for insurance, but it'll be interesting to see if the knock behavior changed with all of the upgrades. Headers just got back from being cryo'd, getting them thermal-coated this week and then it's reassembly time.
FWIW, I ran a huge braided ground strap from the back of the alternator to the frame and also cleaned the grounds at the back of the heads like you did. I changed the fuel filter as well, for good measure - I'm assuming your FP is rising correctly with boost? Upgrading the MEMCAL to #16164174 didn't make any difference with regard to knock, and swapping knock sensors twice didn't help either.
The KR is a PITA with these trucks, I have a feeling I'll have to go to Vortecs to get rid of it completely. Will keep an eye on this post and also let you know if any of my upgrades helped; motor is 70K original stock, unopened, and still running strong.
dgoodhue
BuSTeD 4.3
Re: Knock Retard
In 2001 or 2002, you made a post about knock retard. You, Brian Green and TookyCat went back and forth about potential fixes. (Brian had the ideas) At the time I printed that post out (the post is no in the database, its too old) and I had used it as a reference, but unfortunately I did everyhting in that post and none of it helped.
I am going to add a ground strap the the alternator, its on my to do list. The fuel pressure goes up with boost, fuel filter is relatively new. If anything my truck runs rich. I am going to keep on plugging away.
mrweelr said:
In 2001 or 2002, you made a post about knock retard. You, Brian Green and TookyCat went back and forth about potential fixes. (Brian had the ideas) At the time I printed that post out (the post is no in the database, its too old) and I had used it as a reference, but unfortunately I did everyhting in that post and none of it helped.
I am going to add a ground strap the the alternator, its on my to do list. The fuel pressure goes up with boost, fuel filter is relatively new. If anything my truck runs rich. I am going to keep on plugging away.
dgoodhue
BuSTeD 4.3
Re: Knock Retard
Today I took more timing out (through the TunerPro/Romulator) I had a total of 10 degree out compare to the version 7 ultimate, ( I actuallhave about 8 degree out in Version 11 which has lower timing)
So at 10 degrees timing I have 0 knock retard until the top of 2nd gear (4475), at the top of 2nd I have 4.4 degree spike of knock retard. It started raining out so I won't be tuning the truck anymore today. I am going to try taking out a degree or two of timing @ 4400 so see if I can nip the KR at that point. I am going to slowly add back more timing at the lower RPM to see if I can optimize what I have. Maybe I can get this down to only 8 or 9 degree of timing that has ot be pulled.
I atleast know from 0-55mph, I have no false knock. I was a little worried I might be chasing both false and real.
Today I took more timing out (through the TunerPro/Romulator) I had a total of 10 degree out compare to the version 7 ultimate, ( I actuallhave about 8 degree out in Version 11 which has lower timing)
So at 10 degrees timing I have 0 knock retard until the top of 2nd gear (4475), at the top of 2nd I have 4.4 degree spike of knock retard. It started raining out so I won't be tuning the truck anymore today. I am going to try taking out a degree or two of timing @ 4400 so see if I can nip the KR at that point. I am going to slowly add back more timing at the lower RPM to see if I can optimize what I have. Maybe I can get this down to only 8 or 9 degree of timing that has ot be pulled.
I atleast know from 0-55mph, I have no false knock. I was a little worried I might be chasing both false and real.
92Typhoon1679
Member
Re: Knock Retard
I had kind of the same problem before i changed out the Knock Sensor with a New one the same problem i got a GM-High Tech mag that talked all about Knock sensors i can Scan the article and send it if you want. I found out my knock sensor was screwed in too tight which made it give a False knock. if you want a copy of the article Email me a rosszahara@hotmail.com
I had kind of the same problem before i changed out the Knock Sensor with a New one the same problem i got a GM-High Tech mag that talked all about Knock sensors i can Scan the article and send it if you want. I found out my knock sensor was screwed in too tight which made it give a False knock. if you want a copy of the article Email me a rosszahara@hotmail.com