P1451 and P0306 codes

[ghettoracer]

I got these 2 codes today cause my check engine light tripped yesterday. The P1451 code is the EVAP canister solenoid and the P0306 code is a misfire in #6 cyl. Now can this P1451 code cause the misfire in the #6 cyl? Cause both of them sound related.

 

[ELVATO]

Measure the resistance of the #6 spark plug. It should be between 2000 and 20000 ohms. If not, replace (they are cheap enough, like 3-4 bucks). How many miles do you have on your current plugs?

Swap the #6 COP with another one, disconnect the battery/clear the codes, and see if the misfire follows the COP. Do this after verifying that the spark plug is in working order.

 

[ghettoracer]

The COP and the plug was changed and still tripping the 2 codes so Im thinking the evap purge solenoid is bad and fuel is not getting to that particular cylinder.

 

[ELVATO]

Not sure how. Here's is what the EVAP system as a whole does:

-prevents hydrocarbon emissions from reaching the atmosphere.
-stores fuel vapors in the evaporative emission (EVAP) canister that are generated during vehicle operation or hot soak, until they can be consumed by the engine during normal engine operation.
-routes the stored fuel vapors to the engine during engine operation.
-is controlled by the powertrain control module (PCM) which using various sensor inputs calculates the desired amount of purge flow. The PCM regulates the purge flow, induced by the application of intake manifold vacuum, by varying the duty cycle applied to the EVAP canister purge valve.
-has an evaporative emission (EVAP) test port for test purposes.

Here's what the solenoid does:
-is normally open.
-seals the evaporative emissions system for the OBD II leak and pressure tests.
-is mounted to the evaporative emissions canister.
-is repaired as a separate item.

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If you want to change the solenoid, I have instructions for that. You could try getting one from a junk yard near by, Tasca Parts, ebay, or Rock Auto. Seems it'd be 50ish bucks for a new one, or 30 for the used one on ebay.

 

[ghettoracer]

Yeah instructions would be good on how to do it. Thanks Elevato. Im just sorting out my options before I take it to a dealership. I noticed that going uphill was causing it to hesitate and it was a pretty damn hot day. It hasn't been doing that until just yesterday when it threw the check engine light. My truck was eating a lot more gas than it should of.

 

[ELVATO]

How many miles do you have on your current plugs? Might need to change them. Would be cheaper than changing all the COPs.

 

[ghettoracer]

Its been like 20k since the plugs were changed. How can the EVAP code and misfire on that cylinder be related to the spark plugs? I was looking on the F-150 forums and someone had the exact same issue and engine as I do and he changed out the COPs and the plugs and the evap purge solenoid seemed to be the culprit.

 

[KWT2000]

the po1451 is the emission control evap circuit... most likly the the purge solenoid. could be a blown fuse or the fuel tank pressure sensor/conector. or an open or chafed wire in the system... the missfire and the evap codes will not cause each other

 

[ELVATO]

Alright, I'll post the instructions later tonight.

 

[ghettoracer]

Ok well I took it to a good repair shop, turned out all my spark plugs were bad. LOL my bad. Anyhow, the other code that popped up for the EVAP solenoid turned out to be an electrical issue to the part, so they are going to track it down tomorrow.

Price for all 8 spark plug change: $100
Diagnosis and fix electrical problem: $50
Not getting ripped off at a repair facility: Priceless

 

[ELVATO]

Haha, that sucks. They were 20k old? Parts just don't last like they used to At least you got it figured out.

 

[ghettoracer]

Update: Ok so spending 160 bucks turned out to be a good investment. Changed all 8 spark plugs, changed #6 cyl COP and changed a leaking evap solenoid line. Runs like a champ now, just need to change the fuel filter now and fill up with premium

 

[ELVATO]

I wouldn't put premium unless you are tuned for it (or are pinging). It just encourages carbon deposits. Maybe 89, if you want that boost in octane.