Here’s a quick DIY on a very normal problem for most modern fuel injected engine. Thus far I’ve only run into this issue on GM’s 3.6 litre V6, although it can happen on any brand or make. If you don’t know the GM 3.6 litre engine is pretty ubiquitous throughout the General Motors lineup, found in everything from the Chevy Malibu to basically all Buick’s and Cadillac’s. Having dealt with this issue a few years ago on my wife’s Saturn Vue, when a family member’s Buick Enclave showed up with the same symptoms it was easy to diagnose.

Parts for this DIY:

• New Vapor Canister Vent Valve

Tools You’ll Need:

• A Ratchet Set
• A Screwdriver Set
• A OBD2 Code Reader

The symptom related to a failing vapor purge canister solenoid is difficulty starting after filling up. Basically you’ll go gas up, and when you try to start the car it’ll fight you and not want to run. You’ll have to keep cranking it over and eventually the car will decide to start. It’s not a horrible scenario, but it tends to scare people as they think the issue will be engine related.

The reasoning behind this is that as the solenoid begins to fail, it will remain open. This causes a small vacuum leak. The solenoid’s function is to allow the unburnt fuel gasses to be recycled back into the engine so that they are fully burned. Helping make the process more emissions friendly. When you go fill up this creates a larger than normal amount of fuel vapor, exacerbating the issue. As such you are more likely to notice it after filling up. However, a failing vapor solenoid will not allow an engine to run optimally at all times, so it’s important to address the issue. To make matters more convoluted as well as sending a vapor canister code to the computer, it’ll also send a misfire code for whatever piston was firing at the time. Thus, when you go check your engine codes it’ll look like you have a serious misfire and more potential damage than there really is. The important thing to remember here is that it’ll always manifest itself after you fill up, so if you deal with it quickly there will be no long-term issues.

A vapor purge canister solenoid can be bought basically anywhere. Most local auto parts will have it, as well as Amazon, Rock Auto and of course the dealership. I ended up ordering this one on Amazon (ACDelco 214-2137 GM Original Equipment Vapor Canister Vent Valve) as I wanted it here as soon as possible, even though Rock Auto was a couple bucks cheaper. Overall you shouldn’t spend more than $35-$40 on this part, on the high end.

The actual replacement of the part is very straight forward. You’ll want to remove whatever plastic beauty trim or cover there is to expose the actual engine. Once there you’ll have to locate the part. It is typically located somewhere on the intake manifold. On the Buick it can be found towards the front bumper side of the engine next to the throttle body. After locating the solenoid you’ll have to disconnect the vacuum line going into and out of it, as well as the electrical connector. I’ve never run into an issue where there is a special tool needed for disconnecting any of these, but you never know. Regardless, go ahead and unplug everything and then loosen up the single mounting bolt. Once it is loose you just pull it out. Installation is simply the reverse. Make sure you bolt up the new unit snugly but don’t over tighten it. Reconnect the vacuum lines and you’re good to go. I went ahead and gave the Buick’s engine a good cleaning, as the poor girl was looking a bit haggard.

Ideally you’ll want to clear the engine codes using a code reader, but if one isn’t available to you just unplug your battery for a bit. If everything worked out as it should next time you fill up your gas tank you won’t run into any issue. Pretty straight forward.

The main thing to take away from this is to accurately diagnose the issue and not allow any dubious mechanic to talk you into more work than necessary, especially given the variety of engine codes that can pop up.

This should be a stress-free and straight forward repair. It really might be one of the easiest things you can fix on a modern car. 

Useful Parts & Tools to Help you with this DIY Project: