Does your car ping like this?
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 9,464
Likes: 1
From: Modesto CA
Does your car ping like this?
Sometimes, when my car is idling, and I rev it, JUST as a I hit the gas, I hear what *SOUNDS* like a *ping,ping* it's a weird little noise. Sometimes it does it, sometimes it doesn't. Anyone else have this problem?
Also, when I'm at WOT, and it shifts, it makes a weird pinging sound. My other vette (85/A4) did this aswell. Might it be my actual TIRES making that noise?
Also, when I'm at WOT, and it shifts, it makes a weird pinging sound. My other vette (85/A4) did this aswell. Might it be my actual TIRES making that noise?
Safety Car
Joined: Dec 2000
Posts: 3,767
Likes: 5
From: Jacksonville Fl
Re: Does your car ping like this? (TIMSPEED)
I think they all over-advance timing right off idle, and once the low vacuum from stomping the gas registers, the advance comes off. Could explain why you get a slight amount of ping for a split second.
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 9,464
Likes: 1
From: Modesto CA
Re: Does your car ping like this? (BBA)
Hmm...Never thought of that. That's probably true, the computer advances due to the TPS, which causes the ping. Hmm...ok, that's solved I guess! :crazy:
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: Does your car ping like this? (TIMSPEED)
Hmm...Never thought of that. That's probably true, the computer advances due to the TPS, which causes the ping. Hmm...ok, that's solved I guess! :crazy:
Check your timing. 6.5* BTDC is stock. My car has the TPS at 0.68v @ idle right now and timing is set to 9.5* BTDC with no ping. Unless the gas in CA really sucks, I dunno. I run 94 all the time.
Safety Car
Joined: Dec 2000
Posts: 3,767
Likes: 5
From: Jacksonville Fl
Re: Does your car ping like this? (scorp508)
Scorp, I think you are referring to base timing setting with the EST connector unplugged, where he is talking about off idle WOT ping that goes away under normal driving conditions.
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 9,464
Likes: 1
From: Modesto CA
Re: (scorp508)
Yeah, I checked base timing, and it's at 7º. (That's with the EST connector unplugged.) I think it's just what BBA said. I just can't figure out the thing with the shifts. I think it MIGHT be my tires!
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Le Mans Master
Joined: Jul 1999
Posts: 7,072
Likes: 4
From: Maryland
Re: Does your car ping like this? (TIMSPEED)
Mine does on occasion when I'm really flooring it going up a hill or something. I know I have to back off the timing on the shark by 2 degrees in winter or it pings like hell with this MTBE gas. It wouldn't surprise me if the knock sensor / computer on the C4 isn't quite tuned for the crappy gas. ~Juliet
Advanced
Joined: Apr 2000
Posts: 88
Likes: 0
From: Marietta Ga
Re: Does your car ping like this? (TIMSPEED)
My car and most others I think have a rattle at shut down and start up and at times like you mentioned. It is normal but I do not know what it is. I used to worry about it.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Re: Does your car ping like this? (TomS)
When you suddenly go from cruise, closed loop mode to WOT PE (Power Enrichment) mode, for a brief second the engine is receiving too much timing.
At Closed Loop you may be seeing over 40 degrees of timing with the 02 giving feedback to the ECM, then when you stomp to the floor the ECM switches to PE mode which is based on maps programmed into your PROM and are not effected by 02 feedback.
For the amount of time it takes for the ECM to pull out the required amount of timing, your engine will be seeing too much. The knock sensor is supposed to catch this and pull out timing until the ping ceases, then begin adding timing back in.
But according to some respected sources I've referenced, some amount of ping and knock retard is normal for the type system we have.
I'll bet if you try gradually depressing the pedal to WOT you won't hear any ping at all. That's because the ECM will have time to make the required adjustments.
Try it and keep us posted.
Jake
At Closed Loop you may be seeing over 40 degrees of timing with the 02 giving feedback to the ECM, then when you stomp to the floor the ECM switches to PE mode which is based on maps programmed into your PROM and are not effected by 02 feedback.
For the amount of time it takes for the ECM to pull out the required amount of timing, your engine will be seeing too much. The knock sensor is supposed to catch this and pull out timing until the ping ceases, then begin adding timing back in.
But according to some respected sources I've referenced, some amount of ping and knock retard is normal for the type system we have.
I'll bet if you try gradually depressing the pedal to WOT you won't hear any ping at all. That's because the ECM will have time to make the required adjustments.
Try it and keep us posted.
Jake
