Wierd ping problem
Thread Starter
Instructor
Joined: Aug 2003
Posts: 139
Likes: 0
From: South Cave, Brough East Yorkshire
Wierd ping problem
Hi i got a problem with my 86 auto Pinging.
It only does it at moderate throttle openings though - not at WOT.
I`ve tried altering my timing both ways and nothing seems to make a difference to the ping.
I just can`t understand why it doesn`t do it at WOT - is it something to do with the ecm?
What should i check for to try and elimate it?
It`s not real bad - doesn`t sound like it knocking real bad like a manual car would say at 500 rpm in top gear - but it`s often there in the background and its annoying
Any help is really appreciated cos i don`t wanna start playing arround with stuff when its running so well at WOT...
Tnx guys,
Dom
It only does it at moderate throttle openings though - not at WOT.
I`ve tried altering my timing both ways and nothing seems to make a difference to the ping.
I just can`t understand why it doesn`t do it at WOT - is it something to do with the ecm?
What should i check for to try and elimate it?
It`s not real bad - doesn`t sound like it knocking real bad like a manual car would say at 500 rpm in top gear - but it`s often there in the background and its annoying
Any help is really appreciated cos i don`t wanna start playing arround with stuff when its running so well at WOT...
Tnx guys,
Dom
Advanced
Joined: Feb 2004
Posts: 51
Likes: 0
From: Mission Viejo CA
As previously suggested, are you sure that the noise is "pinging?"
Reset timing to factory specs and ensure that the engine is in a good state of tune. Do you see the Check Engine light while the car is running? I would even see if there are any codes if the light is NOT on. It's possible that you have an EGR system problem. The EGR, when working properly, will "recycle" some of the exhaust gas back into the intake manifold at most operation above idle speed and below WOT. This reduces peak combustion temperatures and the formation of NOX: Smog-producing emissions. If you have a reduction in that flow, combustion temps. will increase; often causing "pinging" at part throttle applications. By design, EGR is essentially "disabled" at WOT.
Good luck and hope this helps....
Reset timing to factory specs and ensure that the engine is in a good state of tune. Do you see the Check Engine light while the car is running? I would even see if there are any codes if the light is NOT on. It's possible that you have an EGR system problem. The EGR, when working properly, will "recycle" some of the exhaust gas back into the intake manifold at most operation above idle speed and below WOT. This reduces peak combustion temperatures and the formation of NOX: Smog-producing emissions. If you have a reduction in that flow, combustion temps. will increase; often causing "pinging" at part throttle applications. By design, EGR is essentially "disabled" at WOT.
Good luck and hope this helps....
Intermediate
Joined: Oct 2000
Posts: 37
Likes: 0
From: McLouth KS 66054 KS
Originally Posted by Total Recall
Hi i got a problem with my 86 auto Pinging.
It only does it at moderate throttle openings though - not at WOT.
I`ve tried altering my timing both ways and nothing seems to make a difference to the ping.
I just can`t understand why it doesn`t do it at WOT - is it something to do with the ecm?
What should i check for to try and elimate it?
It`s not real bad - doesn`t sound like it knocking real bad like a manual car would say at 500 rpm in top gear - but it`s often there in the background and its annoying
Any help is really appreciated cos i don`t wanna start playing arround with stuff when its running so well at WOT...
Tnx guys,
Dom
It only does it at moderate throttle openings though - not at WOT.
I`ve tried altering my timing both ways and nothing seems to make a difference to the ping.
I just can`t understand why it doesn`t do it at WOT - is it something to do with the ecm?
What should i check for to try and elimate it?
It`s not real bad - doesn`t sound like it knocking real bad like a manual car would say at 500 rpm in top gear - but it`s often there in the background and its annoying
Any help is really appreciated cos i don`t wanna start playing arround with stuff when its running so well at WOT...
Tnx guys,
Dom
Thread Starter
Instructor
Joined: Aug 2003
Posts: 139
Likes: 0
From: South Cave, Brough East Yorkshire
Ty 4 ur replies.
Yeah as far as i can tell it`s ping
The check engine light is not on under operating conditions - other than b4 startup ofc - though obviously it does come on when i disconnect that wire that u gotta do whilst altering the timing. I set it to 6 deg as per factory specs.
Now as 4 egr - this is what worries me a bit - cos its all been removed from my car - by a previous owner. I get no check engine lights so i guess it`s been done properly but what descibe sounds a bit too much like what seems to be happening with my car - and yes the hotter it is the worse it is - and i`d swear my car is quicker at part throttle when at normal orperating temp, than when u first drive off when its cold....
I was gonna remove the egr on my fiero - but some1 on that forum said u need a new ecm if ur gonna do that cos the comp automatially advances timing for when the egr is operating - is this the same with L98 vettes ?
Even if it does, the egr temp switch on my car is tucked away in the wiring harness now - so i wouldn`t have thought it would sense its hot enuf to trigger the comp into thinking the egr is on ??
Can u give me a quuick run down of things to do when removing the entire egr system from the car - so that i can check everything has been done. Tnx
As 4 the fuel filter - yeah i`m gonna replace that cos i can tel ljust by lookin at it - its been on for a long time lol - u never know !
Tnx again for the help - ill let u know if i get rid of the problem...
l8rz,
Dom
Yeah as far as i can tell it`s ping
The check engine light is not on under operating conditions - other than b4 startup ofc - though obviously it does come on when i disconnect that wire that u gotta do whilst altering the timing. I set it to 6 deg as per factory specs.
Now as 4 egr - this is what worries me a bit - cos its all been removed from my car - by a previous owner. I get no check engine lights so i guess it`s been done properly but what descibe sounds a bit too much like what seems to be happening with my car - and yes the hotter it is the worse it is - and i`d swear my car is quicker at part throttle when at normal orperating temp, than when u first drive off when its cold....
I was gonna remove the egr on my fiero - but some1 on that forum said u need a new ecm if ur gonna do that cos the comp automatially advances timing for when the egr is operating - is this the same with L98 vettes ?
Even if it does, the egr temp switch on my car is tucked away in the wiring harness now - so i wouldn`t have thought it would sense its hot enuf to trigger the comp into thinking the egr is on ??
Can u give me a quuick run down of things to do when removing the entire egr system from the car - so that i can check everything has been done. Tnx
As 4 the fuel filter - yeah i`m gonna replace that cos i can tel ljust by lookin at it - its been on for a long time lol - u never know !
Tnx again for the help - ill let u know if i get rid of the problem...
l8rz,
Dom
