Just the MAF sensor?

Hey guys.. my lady has a 2002 Tacoma stepside and we constantly smell gas, and the CEL light is always on. I replaced the cap, that didn't do it. Get the occasional misfire too.

Today a mechanic said my problem is the mass airflow sensor (MAF).. being in Vegas it's probably covered in dirt. He said to clean it and then replace it if the problem persists.. I found it for twenty bucks on eBay and it's a simple enough job.

However, at 148k miles in thinking I should change the spark plugs (stock Denzos) and maybe clean the throttle body. Should have her good as new.

Thoughts ?

 

did you get the codes pulled out of the truck? You'll know exactly what is the problem

before you go buy another one, it's easy to clean a MAF sensor, much cheaper than a new one... and by the way, for twenty bucks, chances are high it's a poor quality chinese made p.o.s

at 148k miles, yeah it would be a good idea to replace the original plugs, they have outlived their service life since quite a while.

Anyway, dirty MAF + worn plugs is probably why you're having misfires. So clean your MAF and the throttle body then replace your sparkplugs and get your CEL cleared and if CEL comes back, depending on what is causing it, proceed to replace parts

 

Yeah I got the codes today.. if I showed you would you know? Haha.

We'll, it was a good brand (denso maybe) on eBay. But yeah. The MAF is small, shouldn't cost $160. That's stupid..here it is. Lol.
https://www.ebay.com/p/1250837685?iid=253502687968

Thanks for the advice, I'll do exactly that.

 

Yes, most true auto tech savvy/enthusiasts "would know"--they are the key to unlocking the problems--also, if the plugs are original; at 148k miles, they should have been changed 118k miles ago and 3 or 4 time in-between...

We'll, it was a good brand (denso maybe) on eBay. But yeah. The MAF is small, shouldn't cost $160. That's stupid..here it is. Lol.
https://www.ebay.com/p/1250837685?iid=253502687968

Thanks for the advice, I'll do exactly that.[/QUOTE]

 

yes I would know what the code means. Otherwise I wouldn't try to help out others..

Sensors shouldn't cost that much, I know, but well, it's crazy like that
By the way, I don't think this sensor you found is compatible with 2003 tacoma. The part number for 2001-2004 is 22204-0C010 while 2005+ is

$89 22204-22010 Intake Meter Sub-Assembly

22204-22010

 

I'm working on my wife's 2002 3.4 V6... Not my 2011 in sig.

Plugs have been changed a few times, but it's been a while. Doing the MAF cleaning right now..
Here's my codes

Already replaced the gas cap.. still getting the codes so trying MAF today

 

misfires can also be caused by bad sparkplugs coil packs or wires but I'd only replace the sparkplugs and clean the MAF for now to see if that was the cause of the problem. If still misfiring, replace the packs (or wires, depending on which setup you have)

as for the EVAP system malfunctions, did replacing the cap solve it? If not, then you have a problem or a leak somewhere in your EVAP system

 

Well. Looks like I have packs on the left, wires on the right.. idk. The spark plugs have big squareson the left. And almost nothing but the wires on the right side.

And yeah. I'm doing MAF today and plugs tomorrow... Not sure on the EVAP. I replaced the cap months ago, those codes we're yesterday.

So the MAF won't get rid of EVAP codes? where should I look first for that.

 

That could be a big slew of things related to your fuel, and since you mentioned you're constantly smelling gas that makes sense. I'm just going to list out what comes to my mind.

If I'm in your shoes, I would check all your fuel lines/hoses/fuel filter/joints&connections coming to and from and surrounding the fuel tank. Another spot that seems common is the gasket for where the fuel pump or fuel check valve is inserted may be worn out (I'd suspect this is quite likely the issue). This can be a real goose chase though with so many things being the possible issue, but since we know that you're indeed are smelling gas, I would check for a physical part that is causing a leak along with the other stuff your planning to do (maf cleaning/ changing plugs). This is assuming the gas cap change did not help with the constant gas smell.

Some other things that could be a issue would be a faulty ECU/EMC, perhaps clogged injectors, charcoal canister broken, clogged fuel filter, but I imagine these may be less likely with the symptoms you've listed so far.

 

Thanks for the detailed reply..

So I smell gas occasionally... Only sometimes, but my girl said she smells it pretty often. It does idle a little rough sometimes but for the most part it runs pretty good for having 140k miles.

You guys will love this. While cleaning the MAF I checked the air filter and it's from 2010. Yes this dirty black air filter is 8 years old. Sigh. She felt good because she was changing her oil on her own. But she never had a Jiffy Lube suggest the air filter..... Lol.

 

Safe to say I think a new air filter n cleaning the MAF is a great start. Bahahaha

 

Hm.. that's a lot of things. Should I start with the fuel pump gasket, then check the lines under the truck.. or you mean like all those little air valves under the hood? I looked up the fuel check valve and it requires dropping the gas tank. I don't think I have the tools for that.

 

The EVAP system is mounted onto the tank on 2001-2004, so you'll have to drop it anyway. It's just a few bolts to lower the fuel tank, then undo the gas lines to drop it completely.

 

I'm assuming the work on the maf, filters, and plugs didn't clear any codes?

In terms of the fuel lines, I mean just the lines underneath the truck that come directly from your tank to engine, not so much the ones under your hood. You shouldn't smell any gas coming directly from the lines, fuel filter, or even the tank itself given its sealed correctly. Perhaps if you have truck running you can see any bubbling from the gas seeping outward from the lines/filter.

That all said though, I do imagine the biggest likely culprit would be the fuel check valve and/or fuel pump gasket which are both a pain to access as they require dropping the gas tank. Haha not a easy task at all if you don't have the confidence nor a sturdy jack(s) & jack stands, and the clearance/platform to actually be able to drop it far enough to work on. Definitely a dangerous job that I would caution before doing haphazardly.

Unfortunately I'm not sure how you can for sure check if indeed the gaskets on there are the issue before actually dropping them (or hiring a mechanic), since theres always the chance that its something completely different causing the issue. Actually you can consider using UV dye to try to find the possible leak, but honestly haven't used it myself and I doubt it would reveal the leak if it is indeed those components on the gas tank.

Heres a vid that helped me drop my tank, and is relevant to your evap/P0440 codes if you haven't already seen it. He goes a bit hardcore making a platform for the gas tank which isn't necessary, but helpful for sure (I just used multiple jacks).
https://www.youtube.com/watch?v=D-HPp2-_PFM

 

Thanks for the replies guys.. might take it to the small shop around the corner..

Still need to do my spark plugs this weekend

 

Ok... I'm back @Pervy.

Replaced the gas cap, MAF, Spark plugs, packs, wires and I still got a CEL and a code. Only one code this time.

P0440 is now what I got. Looks like the new spark plugs fixed the misfire.

Any advice on findimg the "fuel pump or fuel check valve" you mentioned earlier? Or is that where I need to drop the gas tank... Hmm. Wondering if a smoke test would find my EVAP problem.

 

should find the problem if they know what their doing.

 

I bought one of those MAF's for my 04. Looked identical to the OEM one I pulled out. About 3500 miles on it, knock on wood, it seems to be working fine.

$89 22204-22010 Intake Meter Sub-Assembly

22204-22010 was the part number, but I didn't buy it through that eBay seller.

 

Yeah I already replaced all that.

Working on EVAP system now. Thx tho