92 corvette failed emissions???
Thread Starter
Intermediate
Joined: Jan 2018
Posts: 48
Likes: 0
NIMBY:= Not In My Back Yard. IOW, I don't want that stuff on my driveway or garage nor do my neighbors want me flushing it down the sewer. I'd gladly do it in YOUR garage and mess up YOUR area but Not In My Back Yard.
I learned I don't want coolant on the driveway. I learned I don't want the wife asking me for weeks "Are you sure you washed everything off?" when she takes the dogs out. I learned I don't want my neighbors seeing me flush stuff down the sewer. I also learned that this is 2018 and almost everyone has a cell phone and camera. If I worked in a shop, I'd DIY if they let me.
Your code 74. Have you got the stock radio and if so, does it dim display? Some have thought that might be the issue.
https://tech.corvettecentral.com/201...trouble-codes/
I learned I don't want coolant on the driveway. I learned I don't want the wife asking me for weeks "Are you sure you washed everything off?" when she takes the dogs out. I learned I don't want my neighbors seeing me flush stuff down the sewer. I also learned that this is 2018 and almost everyone has a cell phone and camera. If I worked in a shop, I'd DIY if they let me.
Your code 74. Have you got the stock radio and if so, does it dim display? Some have thought that might be the issue.
https://tech.corvettecentral.com/201...trouble-codes/
Thread Starter
Intermediate
Joined: Jan 2018
Posts: 48
Likes: 0
Knock Sensor and Code 43 don't have anything to do with those high HC and CO numbers.
A 47.4 CO should be black-smoke exhaust.
Pull the vacuum hose off the fuel pressure regulator and check for liquid fuel in the line. A ruptured diaphragm would introduce raw fuel into the intake, and could cause very high CO.
I've fixed a couple of Code 43's by loosening the knock sensor a 1/2 turn, then retightening it. Because they are in the water jacket, the threads are subject to corrosion and the sensor loosing ground. Disturbing the threads re-establishes the ground and the code should clear. On a car you're selling, worth a try. No parts to buy, or mess to make. I don't drain the cooling system to change them anyway. I take the old one out, and put the new one in. It's only a 3/8" hole, you don't spill more than a couple of ounces.
A 47.4 CO should be black-smoke exhaust.
Pull the vacuum hose off the fuel pressure regulator and check for liquid fuel in the line. A ruptured diaphragm would introduce raw fuel into the intake, and could cause very high CO.
I've fixed a couple of Code 43's by loosening the knock sensor a 1/2 turn, then retightening it. Because they are in the water jacket, the threads are subject to corrosion and the sensor loosing ground. Disturbing the threads re-establishes the ground and the code should clear. On a car you're selling, worth a try. No parts to buy, or mess to make. I don't drain the cooling system to change them anyway. I take the old one out, and put the new one in. It's only a 3/8" hole, you don't spill more than a couple of ounces.
Team Owner
Joined: Jul 2004
Posts: 28,472
Likes: 3,290
From: Hartford WI
5$ bucket 2$ rag 7$ later and you have no mess be carful and nothing can go wrong unless you mess it up then it’s youre fault. I’m not too interested in the code 72 or 74 they come and go which is interesting but 43 is knock sensor and/or optispark failure so how do I test the Opti spark?
Have you tried to take the codes off since they are history codes and see if they reappear? There are we several tests out there on YouTube that show how to test the Opti in the car. Can't vouch for them personally but I'd wipe the codes first
Thread Starter
Intermediate
Joined: Jan 2018
Posts: 48
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I guess it's a question of personal comfort level I stick the garden hose in the block I get more coolant than I am comfortable with on the floor. You may be OK with the amount but I would flush the floor which requires me to remove the floor shelves.
Have you tried to take the codes off since they are history codes and see if they reappear? There are we several tests out there on YouTube that show how to test the Opti in the car. Can't vouch for them personally but I'd wipe the codes first
Have you tried to take the codes off since they are history codes and see if they reappear? There are we several tests out there on YouTube that show how to test the Opti in the car. Can't vouch for them personally but I'd wipe the codes first
Race Director
Joined: Sep 2001
Posts: 14,679
Likes: 752
From: NEwhere Ohio
Thank God Pennsylvania doesn’t require anything more than a visual on C4’s. They do check the gas gas cap though. In fact, less than 5 K miles a year, they are completely exempt. Even with a CES light on.
( actually 2 of mine have Antique tags and don’t even require State Inspection at all )
Probably the only good thing about “ Taxylvania”
( actually 2 of mine have Antique tags and don’t even require State Inspection at all )
Probably the only good thing about “ Taxylvania”
all counties in PA arent the same. Luckily most of PA is rural !
Race Director
Joined: Sep 2001
Posts: 14,679
Likes: 752
From: NEwhere Ohio
there are better technology injectors now that can hold a shorter pulse better (like at idle). Not a bad idea to replace
that being said the emissions targets should be able to be met with your stock system working perfectly which its not.
good luck
Last edited by dizwiz24; Mar 29, 2018 at 10:21 PM.
Team Owner
Joined: Jul 2004
Posts: 28,472
Likes: 3,290
From: Hartford WI
Thread Starter
Intermediate
Joined: Jan 2018
Posts: 48
Likes: 0
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Racer
Joined: May 2013
Posts: 278
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From: Long Valley NJ
Run the car to a 1/4 tank of gas.
Pour 6 bottles of isopropyl (clear gas in the tank).
Jam it HARD through the mountains...really run the gears up and get the car hot.
Pull right in for emissions test with the car white hot. I'm talking....hearing the metal of your exhaust "ting ting tinging"...
Enjoy a perfect score.
Pour 6 bottles of isopropyl (clear gas in the tank).
Jam it HARD through the mountains...really run the gears up and get the car hot.
Pull right in for emissions test with the car white hot. I'm talking....hearing the metal of your exhaust "ting ting tinging"...
Enjoy a perfect score.