Still Coding After These Years...
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 8,175
Likes: 237
From: Philadelphia Burbs
Cruise-In V Veteran
St. Jude Donor '06
Still Coding After These Years...
[1985, A4, G92, stock engine]
...is still coding 43 legitimately, following detonation - in other words this is not a spurious code. I'm wondering if I'm stuck with what I'm getting, because it's much better than it was (it happens far less easily than it did a year ago). So far, this has been done:
timing fixed (was completely out of spec)
new fuel pump (fuel pressure was low)
fixed leaking valve seals
I'm looking for ideas. I can provoke this condition by accelerating from medium throttle to full throttle (i.e. fast merging into high-speed traffic). It does not do this from a standing start into full throttle ('Lauren' flat out loves that condition
). Might it be a transmission kick-down issue? If so, how would I fix it?
...is still coding 43 legitimately, following detonation - in other words this is not a spurious code. I'm wondering if I'm stuck with what I'm getting, because it's much better than it was (it happens far less easily than it did a year ago). So far, this has been done:
timing fixed (was completely out of spec)
new fuel pump (fuel pressure was low)
fixed leaking valve seals
I'm looking for ideas. I can provoke this condition by accelerating from medium throttle to full throttle (i.e. fast merging into high-speed traffic). It does not do this from a standing start into full throttle ('Lauren' flat out loves that condition
). Might it be a transmission kick-down issue? If so, how would I fix it?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
have you adjusted the TV cable?
It's rather easy... on the throttle body are a three cables - the throttle cable, the cruise control and the TV cable. The TV cable controls the transmission kickdown and upshift.
ENGINE OFF!
On the TV cable there is a this metal D shaped button, essentially, that needs to be pressed. Use a big open end wrench and push it in. Then, grab the cable and pull it towards the firewall.
Release the button and then grab the throttle cam and "floor it". this will cause the TV cable to be set in the correct position. It will be tight, so it might require some serious effort to make it go to WOT.
That should fix your problem.
We had the same problem with Bastet44's car about year ago... and this fixed it.
It's rather easy... on the throttle body are a three cables - the throttle cable, the cruise control and the TV cable. The TV cable controls the transmission kickdown and upshift.
ENGINE OFF!
On the TV cable there is a this metal D shaped button, essentially, that needs to be pressed. Use a big open end wrench and push it in. Then, grab the cable and pull it towards the firewall.
Release the button and then grab the throttle cam and "floor it". this will cause the TV cable to be set in the correct position. It will be tight, so it might require some serious effort to make it go to WOT.
That should fix your problem.
We had the same problem with Bastet44's car about year ago... and this fixed it.
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 8,175
Likes: 237
From: Philadelphia Burbs
Cruise-In V Veteran
St. Jude Donor '06
Originally Posted by bogus
have you adjusted the TV cable?
It's rather easy... on the throttle body are a three cables - the throttle cable, the cruise control and the TV cable. The TV cable controls the transmission kickdown and upshift.
ENGINE OFF!
On the TV cable there is a this metal D shaped button, essentially, that needs to be pressed. Use a big open end wrench and push it in. Then, grab the cable and pull it towards the firewall.
Release the button and then grab the throttle cam and "floor it". this will cause the TV cable to be set in the correct position. It will be tight, so it might require some serious effort to make it go to WOT.
That should fix your problem.
We had the same problem with Bastet44's car about year ago... and this fixed it.
It's rather easy... on the throttle body are a three cables - the throttle cable, the cruise control and the TV cable. The TV cable controls the transmission kickdown and upshift.
ENGINE OFF!
On the TV cable there is a this metal D shaped button, essentially, that needs to be pressed. Use a big open end wrench and push it in. Then, grab the cable and pull it towards the firewall.
Release the button and then grab the throttle cam and "floor it". this will cause the TV cable to be set in the correct position. It will be tight, so it might require some serious effort to make it go to WOT.
That should fix your problem.
We had the same problem with Bastet44's car about year ago... and this fixed it.
I'll give it a try...it almost feels like I'm being picky, because, thanks to you (and a few others) this 1985 is massively better than when I took ownership - but I would still like to do a spirited drive with no codes.
BTW, say hello to your lady from me and my lady.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
My book indicates a code 43 is tied to the knock sensor. Check the above first. If that doesn't correct the problem, then check the knock sensor (passanger side of the block down low and toward the front). Since you are not the original owner, any chance there is an after market chip? I installed a Hypertech right after I got my 85 and fought the PING constantly. It turned out to be the chip advancing the distributor too much at WOT and subtracting fuel at the same time. Good luck on your quest!
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by j3studio
Andy,
I'll give it a try...it almost feels like I'm being picky, because, thanks to you (and a few others) this 1985 is massively better than when I took ownership - but I would still like to do a spirited drive with no codes.
BTW, say hello to your lady from me and my lady.
I'll give it a try...it almost feels like I'm being picky, because, thanks to you (and a few others) this 1985 is massively better than when I took ownership - but I would still like to do a spirited drive with no codes.
BTW, say hello to your lady from me and my lady.
You are not being picky... ping is potentially dangerous.
Did you get an email from bastet44?
Last edited by bogus; Jun 22, 2005 at 02:22 AM.
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 8,175
Likes: 237
From: Philadelphia Burbs
Cruise-In V Veteran
St. Jude Donor '06
Thanks to all for your responses.
First of all, this is a classic reason why the forum is so valuable. I had read about adjusting the TV cable in the manual, but was missing the important contextual information that Bogus provided:
"Release the button and then grab the throttle cam and "floor it". this will cause the TV cable to be set in the correct position. It will be tight, so it might require some serious effort to make it go to WOT." (italics added)
This was all important - my previous attempts at adjusting had been half-hearted because I was afraid that I was about to break something (else).
Now for the not-so-good news - though once again things were significantly better, I was still able to provoke detonation and then code 43, by first accelerating slowly and than hammering it.
Some more notes:
1) The knock sensor has been replaced
2) There is no aftermarket chip
What else is possible? Exhaust (my mufflers are dodgy, I don't know about my catalytic converter) ? Cooling (temps seem relatively normal) ? Something else?
First of all, this is a classic reason why the forum is so valuable. I had read about adjusting the TV cable in the manual, but was missing the important contextual information that Bogus provided:
"Release the button and then grab the throttle cam and "floor it". this will cause the TV cable to be set in the correct position. It will be tight, so it might require some serious effort to make it go to WOT." (italics added)
This was all important - my previous attempts at adjusting had been half-hearted because I was afraid that I was about to break something (else).
Now for the not-so-good news - though once again things were significantly better, I was still able to provoke detonation and then code 43, by first accelerating slowly and than hammering it.
Some more notes:
1) The knock sensor has been replaced
2) There is no aftermarket chip
What else is possible? Exhaust (my mufflers are dodgy, I don't know about my catalytic converter) ? Cooling (temps seem relatively normal) ? Something else?
Last edited by j3studio; Jun 22, 2005 at 08:40 PM.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by j3studio
What else is possible?
RACE ON!!!
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 8,175
Likes: 237
From: Philadelphia Burbs
Cruise-In V Veteran
St. Jude Donor '06
Originally Posted by CFI-EFI
In the opening post you stated, "...is still coding 43 legitimately, following detonation". Have you verified that the knock counts are truly the result of detonation? How have you checked or tested for detonation?
I'm not trying to be flippant - I have actually verified with several fairly qualified individuals that what I am hearing is detonation. The Check Engine light goes on immediately following this (ugly) sound.
Last edited by j3studio; Jun 22, 2005 at 08:12 PM.
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Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
There is something wrong there. The ESC should cause the ECM to retard the timing to prevent audible knock. Have you checked the ESC module? Follow the trouble shooting chart in your FSM for the ESC modual.
RACE ON!!!
RACE ON!!!
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 8,175
Likes: 237
From: Philadelphia Burbs
Cruise-In V Veteran
St. Jude Donor '06
Originally Posted by CFI-EFI
There is something wrong there. The ESC should cause the ECM to retard the timing to prevent audible knock. Have you checked the ESC module?
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by j3studio
Do I understand correctly that I shouldn't hear the detonation and that the first sign of trouble should be the Check Engine light if the ESC is working correctly?
I would STILL like to know how this problem got tied onto a TV cable adjustment. BOGUS???
RACE ON!!!
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
I have found that if the TV cable is not correctly adjusted, it will cause lugging of the engine.
bastet44's car had a series of problems surrounding spark knock and ping. I first reset the TV cable, which did help somewhat, but then acquired a timing light and that downright fixed it.
no one has asked this question - what is the condition of the distributor?
bastet44's car had a series of problems surrounding spark knock and ping. I first reset the TV cable, which did help somewhat, but then acquired a timing light and that downright fixed it.
no one has asked this question - what is the condition of the distributor?
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 8,175
Likes: 237
From: Philadelphia Burbs
Cruise-In V Veteran
St. Jude Donor '06
Originally Posted by bogus
No one has asked this question - what is the condition of the distributor?
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 8,175
Likes: 237
From: Philadelphia Burbs
Cruise-In V Veteran
St. Jude Donor '06
Originally Posted by j3studio
The knock sensor has been replaced
1) Have I been missing the point all along - that the knock sensor is not sensitive enough to get any but the most obvious (audible) knock, and that any effectively working knock sensor would be sending a signal to the ESC much earlier to retard the spark slightly, which I wouldn't hear and wouldn't cause a code?
2) If I replace the knock sensor, is there any downside to getting the (supposedly better) 1987-1989 or even 1990-1991 knock sensor instead of the pure stock 1984-1986 part? I don't think the NCRS will dock me for an incorrect knock sensor.
3) Is getting the old knock sensor out and the new one in tough? I don't have my manual with me right now, but I seem to remember that there are specific torque wrench settings required.
Sometimes this car makes me feel like a real idiot...
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
My knock sensor was picking up false knock, and retarding my timing for no legitimate reason. I have perminently disconnected my knock sensor. My present knock sensor, is my ear. You may want to temporarilly disconnect yours to check to see if you notice any difference.
1.) Yes. Either that or the ESC simply isn't doing it's job.
2.) I don't know that a later sensor is any advantage, but there is a later module that is less sensitive. I believe 65Z01 has it posted in a tech tip.
3.) I have never done it. It is screwed in to the block water drain hole in the right side of your block, just ahead of the front of the starter.
RACE ON!!!
PS. Bogus, thank you.
Originally Posted by j3studio
1) Have I been missing the point all along - that the knock sensor is not sensitive enough to get any but the most obvious (audible) knock, and that any effectively working knock sensor would be sending a signal to the ESC much earlier to retard the spark slightly, which I wouldn't hear and wouldn't cause a code?
2) If I replace the knock sensor, is there any downside to getting the (supposedly better) 1987-1989 or even 1990-1991 knock sensor instead of the pure stock 1984-1986 part? I don't think the NCRS will dock me for an incorrect knock sensor.
3) Is getting the old knock sensor out and the new one in tough? I don't have my manual with me right now, but I seem to remember that there are specific torque wrench settings required.
2) If I replace the knock sensor, is there any downside to getting the (supposedly better) 1987-1989 or even 1990-1991 knock sensor instead of the pure stock 1984-1986 part? I don't think the NCRS will dock me for an incorrect knock sensor.
3) Is getting the old knock sensor out and the new one in tough? I don't have my manual with me right now, but I seem to remember that there are specific torque wrench settings required.
2.) I don't know that a later sensor is any advantage, but there is a later module that is less sensitive. I believe 65Z01 has it posted in a tech tip.
3.) I have never done it. It is screwed in to the block water drain hole in the right side of your block, just ahead of the front of the starter.
RACE ON!!!
PS. Bogus, thank you.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by j3studio
I was wrong here - I don't believe the knock sensor has been replaced. Some questions:
1) Have I been missing the point all along - that the knock sensor is not sensitive enough to get any but the most obvious (audible) knock, and that any effectively working knock sensor would be sending a signal to the ESC much earlier to retard the spark slightly, which I wouldn't hear and wouldn't cause a code?
1) Have I been missing the point all along - that the knock sensor is not sensitive enough to get any but the most obvious (audible) knock, and that any effectively working knock sensor would be sending a signal to the ESC much earlier to retard the spark slightly, which I wouldn't hear and wouldn't cause a code?
2) If I replace the knock sensor, is there any downside to getting the (supposedly better) 1987-1989 or even 1990-1991 knock sensor instead of the pure stock 1984-1986 part? I don't think the NCRS will dock me for an incorrect knock sensor.
3) Is getting the old knock sensor out and the new one in tough? I don't have my manual with me right now, but I seem to remember that there are specific torque wrench settings required.
Sometimes this car makes me feel like a real idiot...