Knock sensor Q's: How to tell real detonation from false
Thread Starter
Banned
Joined: Jul 2000
Posts: 1,384
Likes: 0
Knock sensor Q's: How to tell real detonation from false
With my auto xray I noticed I'm getting knock retard . Anywhere from 7-16 degrees at WOT. I can't hear any pinging or knocking so I think it may be drivetrain noise or my roller rockers fooling the knock sensor. Anyone else experience anything like this?
------------------
91 Formula
305 TPI 5speed
1LE/G92/WS6
Paxton SN92 polished kit, SLP airfoil, ported/polished plenum, March pulleys, Crane AFPR(43psi),Crane Gold 1.6rrs,MSD coil,MSD6AL (5275rpm limit),Holley 9mm wires,Ac delco R43ts plugs,fastchip,Ford SVO 24# injectors,Bosch O2sensor,SLP 1 5/8" headers,SLP catback,shortened shifter,3:73s w/Auburn posi,170* t-stat,JET 195* fan switch, Macewen white face gauges, Autometer gauges, Zoom hi-performance clutch.
------------------
91 Formula
305 TPI 5speed
1LE/G92/WS6
Paxton SN92 polished kit, SLP airfoil, ported/polished plenum, March pulleys, Crane AFPR(43psi),Crane Gold 1.6rrs,MSD coil,MSD6AL (5275rpm limit),Holley 9mm wires,Ac delco R43ts plugs,fastchip,Ford SVO 24# injectors,Bosch O2sensor,SLP 1 5/8" headers,SLP catback,shortened shifter,3:73s w/Auburn posi,170* t-stat,JET 195* fan switch, Macewen white face gauges, Autometer gauges, Zoom hi-performance clutch.
TGO Supporter
Joined: Aug 1999
Posts: 14,811
Likes: 1
From: Jackson County
yeah it happens. you can detune your senser with a couple of wraps of tefelon tape.
------------------
ICON Motorsports
1st & 3rd
------------------
ICON Motorsports
1st & 3rd
Member
Joined: Mar 2001
Posts: 163
Likes: 0
From: New Windsor, MD
Hi guys,
I'm pretty new at this board thing so please bare with me. I recently experienced the knock/timing retard 'scare' while entering the onramp of a highway. Man, did that suck! Just before it happened I was waiting in heavy traffic. Heavy enough to send the temp over the 220 mark (tipical stuff).
I think since this was the first time my car sat idling and heating up like that (while I had it) that the combination of a slightly higher than needed temp and accelerating onto the highway caused a disturbance or maybe a knock in the lower end of the block which triggered the knock sensor message. SES light etc...
What do you think? Was your engine 'hot' at the time it happened to you? Just wondering.
nFORM91
------------------
Proud newly acquired '91 Formula 305 TPI a4, 34K miles, Factory Black on Black all stock - no current mods (might keep that way!). Rims are '91 T/A black Diamond Spoke 16x8s. 20% tint & Black Widow Alarm system. Very near future plans: K&N filter, catback Flows, fresh paint job, new 255ZRs all around.
I'm pretty new at this board thing so please bare with me. I recently experienced the knock/timing retard 'scare' while entering the onramp of a highway. Man, did that suck! Just before it happened I was waiting in heavy traffic. Heavy enough to send the temp over the 220 mark (tipical stuff).
I think since this was the first time my car sat idling and heating up like that (while I had it) that the combination of a slightly higher than needed temp and accelerating onto the highway caused a disturbance or maybe a knock in the lower end of the block which triggered the knock sensor message. SES light etc...
What do you think? Was your engine 'hot' at the time it happened to you? Just wondering.
nFORM91
------------------
Proud newly acquired '91 Formula 305 TPI a4, 34K miles, Factory Black on Black all stock - no current mods (might keep that way!). Rims are '91 T/A black Diamond Spoke 16x8s. 20% tint & Black Widow Alarm system. Very near future plans: K&N filter, catback Flows, fresh paint job, new 255ZRs all around.
TGO Supporter
Joined: Jul 1999
Posts: 10,907
Likes: 5
From: The Bone Yard
Car: Death Mobile
Engine: 666 c.i.
Do not assume that an "inaudible" knock is a false knock. Most likely you ARE having knock occur and the eprom's "attack/decay" rates are kicking in. You could lower these "attack/decay" rates to have less effect. But be forewarned that you are likely to turn that "inaudible" knock into an "audible" knock if the ecm does not pull out enough timing when it first detects some "knock". This is one of those areas you have "play with" when burning an eprom to get it optimized for your engine.
On a naturally aspirated engine this is not as much of a worry as an unnaturally aspirated engine.
On a naturally aspirated engine this is not as much of a worry as an unnaturally aspirated engine.
Thread
Thread Starter
Forum
Replies
Last Post
