Help please - can't stop the pinging!!!
Thread Starter
Racer
Joined: Apr 2002
Posts: 287
Likes: 6
From: St Albert Alberta
Help please - can't stop the pinging!!!
Hello all,
Firstly thank you Agent 86 for the diagram as it allowed me to diagnose the code 32 and correctly replace the EGR temp/diag sensor/switch.
I no longer have any codes however I continue to have a ping problem. I have cleaned the throttle body, MAF and replaced gaskets on the TB and EGR valve as they were in bad shape. I figured perhaps outside air was getting in past the gaskets. The valve looks newer and compresses very well so I didn't replace it. I use premium fuel (91 octane) and have tried many different brands to no avail. My reading on the forums etc seems to indicate a lack of EGR gas entering the manifold causing the pinging. The engine was rebuilt prior to me buying the car with less than 10k miles on it and other than the ping runs very well.
Could the EGR valve be bad or should I be addressing another area? Engine timing is at 6* with wire disconnected. I know this car should pull better than it does when its warm before the knock sensor does its work pulling back timing. Before she's at operating temperature its much stronger (obviously).
Thanks everyone
Firstly thank you Agent 86 for the diagram as it allowed me to diagnose the code 32 and correctly replace the EGR temp/diag sensor/switch.
I no longer have any codes however I continue to have a ping problem. I have cleaned the throttle body, MAF and replaced gaskets on the TB and EGR valve as they were in bad shape. I figured perhaps outside air was getting in past the gaskets. The valve looks newer and compresses very well so I didn't replace it. I use premium fuel (91 octane) and have tried many different brands to no avail. My reading on the forums etc seems to indicate a lack of EGR gas entering the manifold causing the pinging. The engine was rebuilt prior to me buying the car with less than 10k miles on it and other than the ping runs very well.
Could the EGR valve be bad or should I be addressing another area? Engine timing is at 6* with wire disconnected. I know this car should pull better than it does when its warm before the knock sensor does its work pulling back timing. Before she's at operating temperature its much stronger (obviously).
Thanks everyone
Team Owner
Joined: Jan 2003
Posts: 20,314
Likes: 245
From: Summerland B.C. Canada
Is your knock sensor working properly ?? I deleted the EGR on my stock motor and on my modded 355, and have yet to hear a ping. I did run a 160 stat on the stocker and a 170 on the 355.
Have you tried retarding the timing a tad ?? TPS is set correctly ??
Sorry i don't have a good answer for you
Have you tried retarding the timing a tad ?? TPS is set correctly ??
Sorry i don't have a good answer for you
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
My pinging problem was cause by a restricted exhaust, and non-foulers that Bubba put on the sparkplugs...
Otherwise, go over your ESC system. I'm not familiar with how your year operates, but a little research should reveal that to you.
Oh... and for my pining problem I retarded my timing to 0*. An ugly bandaid, but it worked well (stopped the pinging), until I was able to determine the real cause...
Otherwise, go over your ESC system. I'm not familiar with how your year operates, but a little research should reveal that to you.
Oh... and for my pining problem I retarded my timing to 0*. An ugly bandaid, but it worked well (stopped the pinging), until I was able to determine the real cause...
Burning Brakes
Joined: Jan 2006
Posts: 854
Likes: 1
From: The burbs of Denver CO
Jayman, I'm not sure what ignition system your 89 runs, if you are using stock. Drop us some more info. There are different problems that can cause pinging, including some odd ones like carbon build up.
Race Director
Joined: Dec 2000
Posts: 17,551
Likes: 26
From: El Paso Texas
You shouldn't have ANY pinging at 6 degrees. I'm running 10 degrees base timing, regular fuel, no pinging on a 146K engine.
It's much stronger when colder because it's in open loop. Which tells me a sensor is sending some funky info once it goes into closed loop.
It's very possible a dead O2 sensor is causing a very lean condition. They can go back and still not throw a code. How old are the O2 sensors? Do you have access to an ALDL scanner that will give you real time info as to what's occuring when it goes into closed loop? I'm betting your air fuel mixture is all over the map.
It's much stronger when colder because it's in open loop. Which tells me a sensor is sending some funky info once it goes into closed loop.
It's very possible a dead O2 sensor is causing a very lean condition. They can go back and still not throw a code. How old are the O2 sensors? Do you have access to an ALDL scanner that will give you real time info as to what's occuring when it goes into closed loop? I'm betting your air fuel mixture is all over the map.
Thread Starter
Racer
Joined: Apr 2002
Posts: 287
Likes: 6
From: St Albert Alberta
Hey Frizlefrak, you're right about the timing and you make a good point about the O2 sensor causing a lean condition too. My investigation so far has pointed to a lean condition but not the particular cause of it. I'm going to attempt to get it an a machine later this week.
thebeerman the car is completely stock including ignition.
rick lambert a bad EGR can cause the problem - any idea how to diagnose?
mikey whipreck what is the ESC sytem please?
AGENT 86 is there a way to test that knock sensor? After about a second of pinging it stops. I 'think' that the sensor is retarding the timimg and doing its job, but I could be mistaken.
Thanks everyone,
thebeerman the car is completely stock including ignition.
rick lambert a bad EGR can cause the problem - any idea how to diagnose?
mikey whipreck what is the ESC sytem please?
AGENT 86 is there a way to test that knock sensor? After about a second of pinging it stops. I 'think' that the sensor is retarding the timimg and doing its job, but I could be mistaken.
Thanks everyone,
Race Director
Joined: Dec 2000
Posts: 17,551
Likes: 26
From: El Paso Texas
All you need to test the knock sensor is a timing light and a rubber mallet. Run the engine up to temp, have an assistant run the RPM up to say 2500, aim the timing light at the balancer. Give the engine a good smack with the rubber mallet and your timing should quickly retard.
I really think you're seeing a serious lean condition which is causing the pinging. Could be caused by any number of factors.
One other question....on your engine rebuild, were the stock heads and pistons used, or was compression bumped up significantly?
I really think you're seeing a serious lean condition which is causing the pinging. Could be caused by any number of factors.
One other question....on your engine rebuild, were the stock heads and pistons used, or was compression bumped up significantly?
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Thread Starter
Racer
Joined: Apr 2002
Posts: 287
Likes: 6
From: St Albert Alberta
Okay I will check on that knock sensor too. To my knowledge it was rebuild to stock specs and yes I totally agree that it is running lean.
When I get it on the scanner I'll have these looked at.
I'll let you know.
When I get it on the scanner I'll have these looked at.
I'll let you know.