Failed smog
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Laughing Gas
Joined: Jan 2023
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Failed smog
I just took my truck in and it failed smog. It's a 1988 F-150 302 v8 with an AOD. The NO(PPM) was too high, the max for that on my truck at 15mph is 699 and at 25mph the max is 601. Mine measured 890 at 15mph, and 784 at 25mph. I just pulled KOEO codes from it and I got
44- AIR system inoperative – Air Injection
34- EVP – (R) EGR did not respond properly during test – EVP
EVR – (O, R, M) EVP sensor is/was high – EVR
PFE – (O, R, M) PFE sensor is/was out of range – PFE
Could be any of these for code 34?
25- Knock sensor not tested (ignore if not pinging) – KS. It did ping like mad when I gave it the full throttle for the test. But it never pings daily driving it.
All of these codes were on my last test about a month ago. The battery has been disconnected between then and now. I was wondering where I should go from here to fix it? I do have a vacuum leak on the intake manifold and a broken vacuum line to the vacuum reservoir. On the smog sheet it says that EGR functionable is not applicable. The air injection did pass, and the vacuum line to sensors/switches did pass.
44- AIR system inoperative – Air Injection
34- EVP – (R) EGR did not respond properly during test – EVP
EVR – (O, R, M) EVP sensor is/was high – EVR
PFE – (O, R, M) PFE sensor is/was out of range – PFE
Could be any of these for code 34?
25- Knock sensor not tested (ignore if not pinging) – KS. It did ping like mad when I gave it the full throttle for the test. But it never pings daily driving it.
All of these codes were on my last test about a month ago. The battery has been disconnected between then and now. I was wondering where I should go from here to fix it? I do have a vacuum leak on the intake manifold and a broken vacuum line to the vacuum reservoir. On the smog sheet it says that EGR functionable is not applicable. The air injection did pass, and the vacuum line to sensors/switches did pass.
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Laughing Gas
Joined: Jan 2023
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It drives good misfire at idle in drive, thinking because of the manifold leak. I bought the gasket kit for it. I never saw any smoke from the lower manifold when it was smoke tested so im not gonna reseal that since that's a lot more work. I didn't disconnect it for resetting the codes I just had to for something else so that's why I mentioned that since the codes came back that means that they are current.
Fleet Mechanic
Joined: Nov 2022
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It drives good misfire at idle in drive, thinking because of the manifold leak. I bought the gasket kit for it. I never saw any smoke from the lower manifold when it was smoke tested so im not gonna reseal that since that's a lot more work. I didn't disconnect it for resetting the codes I just had to for something else so that's why I mentioned that since the codes came back that means that they are current.
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Laughing Gas
Joined: Jan 2023
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I’ve recently done the timing chain and timed it. I’ll check it again when I have a chance, and I just bought the manifold gaskets.
Fleet Mechanic
Joined: Nov 2022
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DId you unplug the SPout connector when you timed it?
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Laughing Gas
Joined: Jan 2023
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I did unplug the SPOUT. It really confuses me that it failed since last time there were countless vacuum leaks I didn’t know about. Now there’s 2. I just fixed one of them. But now I need to find time to do the manifold. And anything else that may cause it to have high NOx.
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Laughing Gas
Joined: Jan 2023
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I’m worried it’s more than the intake manifold as well. It has exhaust leak(s) before the catalytic converter, it has EGR codes. Last smog it was a closer shop, no freeway driving, and it wasn’t driven hard but more vacuum leaks. This time it was driven hard to heat the cat, was driven on the freeway, farther, and it had a new timing chain. I hit the remote start as well to keep it running with the key out to keep it hot this time, last time it was shut off while I signed in.
Lead Driver
Joined: Sep 2002
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From: North Texas
Sort your lean issue, that should absolve the issues. Just plug anything not critical at the vacuum tree.
1.5% CO is about 14:1...yours reports 0 if I read that correctly.
What state needs a 35 year old vehicle smogged?
1.5% CO is about 14:1...yours reports 0 if I read that correctly.
What state needs a 35 year old vehicle smogged?
Fleet Mechanic
Joined: Nov 2022
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I'd say hitmanx is right, sort the lean condition and go from there.
Check out your EGR valve, IIRC it can cause a lean condition if it fails.
Fleet Mechanic
Joined: Nov 2022
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I'd say hitmanx is right, sort the lean condition and go from there.
Check out your EGR valve to, IIRC it can cause a lean condition if it fails.