"Ping" issue Revistited- 2000 Corolla

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3,669
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Phoenix, AZ
I've posted about this before, just thought I would bring it up again w/ a couple of things to add. Anyways, our 2000 Corolla currently has 152K miles. At around 100K miles, it developed a ping. The said ping, usually occurs at speeds of 55-70. From my readings, it seems this issue is relatively common to this generation of 1ZZFE. Since the ping began, we've replaced parts and tried various things. -Catalytic Converter/o2 sensors(check engine light). -PCV Valve. -2 MAF Cleanings. -1 Seafoam treatment(had to replace cat shortly after, related??). -2 ARX Clean/Rinses. -Multiple Fuel treatments. -Spark Plugs. Now for the things to add; when we travel up North, up to 7500 ft. elevation, the car doesn't ping much/ever. The car doesn't have an EGR valve, but does have a knock sensor. I've thought about the knock sensor, but it's pricey and hasn't thrown a code for it. I'm currently running MMO every tank or every other tank to see if it helps. Does anyone have any ideas on what could be causing the ping, and what I can do to try and alleviate it? Feel free to ask questions. Any input appreciated.
 
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35,998
Location
ME
can always rap on the idling motor with a wrench, lifting hook loops and accessory brackets are good for this, if the idle changes the knock sensor is working at least to a degree.
 
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25,045
Location
ON, Canada eh?
Did you do a tune-up? Also check into a malfunctioning 02 sensor causing the wrong mixture. A way to test is to disconnect and see if the ping gets better. Also make sure that the thermostat you are using is the right temperature for that engine I would say something in the 180's is fine for where you live.
 
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6,991
Location
Everett, Washington
I have a Ford Taurus engine that started pinging not long after a PCM reprogram. The Auto-RX got rid of it. When I don't put in a maintenance dose the ping starts coming back. Then I put a maintenance dose back in and it starts going away. The pinging is very irritating, so I feel your pain.... The RX did nothing?
 
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19,479
Location
Chicago Area
I'm not so sure that you don't have an EGR vavle. A quick Google says that you should, @ $135.00 That would be my first suspect. Running too hot is #2. Clean the combustion chambers with strong Chevron Techron run through the gas tank. Using one grade more octane fuel is a good cure.
 
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25,045
Location
ON, Canada eh?
No Check engine light? Generally all EGR's today have a feedback of some sort to the ECM for better control, and if the EGR was plugged or not functioning it would/should set a CEL.
 
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2,097
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kansastan
I know next to nothing about Yotas. But as a rule of thumb, an EGR failure won't always throw a code. It SHOULD. But in practice, for whatever reason, I've seen lots of non-functional EGR systems with no accompanying code.
 

panthermike

Thread starter
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3,669
Location
Phoenix, AZ
As for a timing belt, this car has a chain. If you can find the EGR Valve Mechtech, I'm all ears. When I go to parts websites, no one lists an EGR. As for higher octane, we tried once, but only one tank. Perhaps we should try a few w/ 89. ZZman, thanks for the link, good read. I think I may run another top end cleaner through it. I'll also try another round of fuel cleaner. I've been running MMO, 4oz/10gallons for a few tanks, but I'll try some more SI-1 or Techron soon. According to this site, this engine has a 10:1 compression ratio? If so, running a higher octane could make sense right? http://www.spyderchat.com/1zzfe.pdf Thanks for the input thus far everyone.
 
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25,045
Location
ON, Canada eh?
My engine is a 10:1 and I use 87 just fine... I think you should check your thermostat. Could be lazy and running the engine just hot enough to ping, but not enough to send warning signals on your temperature gauge. My Scan gauage will show my engine running at 212oF and the temperature gauge equipped in the car is the same reading when it's at 188oF
 

panthermike

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3,669
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Phoenix, AZ
When the ping first began, that was one of the first things we did. Toyota put in fresh Pink Antifreeze and a new thermostat. Maybe I'll change it again, just because?
 
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25,045
Location
ON, Canada eh?
Is your rad fan coming on early enough? Is the radiator or water pump not up to par? Can they hook it up to an emission machine so you can see what kind of numbers you are getting? If the NOX are too high it could be running too hot and causing your pinging problem either because of a defective EGR (i know you said you don't have one), or because of a blockage in the exaust like a plugged converter, or wrong fuel mixture because of a bad O2 or bad ECM not adjusting the timing or mixture properly. (highly doubt the ECM though...) Does this engine have VVT?
 

panthermike

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3,669
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Phoenix, AZ
 Originally Posted By: StevieC
Is your rad fan coming on early enough? Is the radiator or water pump not up to par? Can they hook it up to an emission machine so you can see what kind of numbers you are getting? If the NOX are too high it could be running too hot and causing your pinging problem either because of a defective EGR (i know you said you don't have one), or because of a blockage in the exaust like a plugged converter, or wrong fuel mixture because of a bad O2 or bad ECM not adjusting the timing or mixture properly. (highly doubt the ECM though...)
Possibility I guess. Only thing is that after the ping began, the cat, and o2 sensors were replaced at around 120K. Is it easy to tell if the ECM were the culprit?
 
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25,045
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ON, Canada eh?
You could check spark timing with a timing light hooked up to Cylinder #1 and if it's out or fluctuating at idle and not on the spec as per Toyota this would indicate that the ECM isn't correctly timing the spark. Could be a nock sensor too... I'm currently checking the forums where professional mechanics like my dad are members and can see actual postings from only other mechanics to see what I can come up with... It is a VVT Engine?
 

panthermike

Thread starter
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3,669
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Phoenix, AZ
 Originally Posted By: StevieC
You could check spark timing with a timing light hooked up to Cylinder #1 and if it's out or fluctuating at idle and not on the spec as per Toyota this would indicate that the ECM isn't correctly timing the spark. Could be a nock sensor too... I'm currently checking the forums where professional mechanics like my dad are members and can see actual postings from only other mechanics to see what I can come up with... It is a VVT Engine?
Thanks for looking into that! Yes, VVT-i engine(1ZZFE).
 
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25,045
Location
ON, Canada eh?
Ok, So here is what I found... They are saying that this should be checked in this order until the ping problem is solved: 1) EGR (If Equipped) 2) O2 Sensor (Switching from Rich/Lean and cycling) Not cycling is a bad 02, ECU or Vacuum leak. 3) MAF Sensor 4) Knock Sensor - Check (easy) by filling up the tank full with premium and adding an octane booster to get you into the 100's. If it still pings it's bad. 5) Check VVTI Actuator located on the front of the engine (easy to change @ $150) 6) Check timing to make sure it's within the spec degree at idle 7) Bad ECU
 

panthermike

Thread starter
Messages
3,669
Location
Phoenix, AZ
 Originally Posted By: StevieC
Ok, So here is what I found... They are saying that this should be checked in this order until the ping problem is solved: 1) EGR (If Equipped) 2) O2 Sensor (Switching from Rich/Lean and cycling) Not cycling is a bad 02, ECU or Vacuum leak. 3) MAF Sensor 4) Knock Sensor - Check (easy) by filling up the tank full with premium and adding an octane booster to get you into the 100's. If it still pings it's bad. 5) Check VVTI Actuator located on the front of the engine (easy to change @ $150) 6) Check timing to make sure it's within the spec degree at idle 7) Bad ECU
Wow, thank you very much. Looks like I got myself a list now .
 
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