Strange Misfire Issue Related to Charcoal Canister?

Hi,

I have this strange issue with the 2.7 4cyl in my 02 Tacoma.

When I start it up cold it's been running fine, when I park it to go into the store or something then restart it, the idle is real rough and cylinder 3 isn't even firing at all. Never happens while I'm driving. If I just take off while its happening and just start driving like normal, the cylinder will suddenly kick back on and truck drives begins running fine. If I let it cool down and then start it, it never happens. Only when it's still hot.

First I changed the sparks and coils on all cylinders since I've been meaning to do that anyways. Then I ran 3 cans of Seafoam through the gas tank and one can through the throttle body. Then I did an oil change to remove any of the carbon deposits I may have washed out.

I cleaned the MAF sensor with a spray cleaner and also changed the air filter.

If I listen to the injectors with my stethoscope, I can hear all of them ticking. Cylinder three included.

CEL blinks when the cylinder stops firing, and then comes on solid. Over the past week I've collected these various codes. Not all at the same time, and some of them have yet to return.

P0100: Mass or Volume Air Flow A Circuit
P0110: Intake Air Temperature Sensor 1 Circuit
P0171: System Too Lean Bank 1
P0300: Random/Multiple Cylinder Misfire Detected
P0302: Cylinder 2 Misfire Detected (This happened once, since then it has just been Cyl. 3)
P0303: Cylinder 3 Misfire Detected
P0401: Exhaust Gas Recirculation Flow Insufficient Detected

The Exhaust gas code is interesting because I just had an evap code a few months ago that I fixed by replacing the charcoal canister. Still, I wonder if that wasn't the whole story.

My plan it to change the MAF and maybe find someone to do a smoke test.
As for compression, I haven't had it tested yet, but I'm not convinced that its the problem since the misfire will suddenly disappear after driving about half a mile.

Thought I would post it here and see if anyone has any ideas (or even cares haha)

Thanks

 

401 just means the EGr ain’t working. Shouldn’t affect anything important. Do a compression test.

 

And check valve shim clearance. If compression is low and valve shims are out of spec, changing them can improve compression and thus help with the misfire.

 

And I’d say just cuz your injectors are ticking doesn’t mean they’re all working right. Mine were, but I sent them off to be serviced at LCE and they told me one was shot. So they refurbed 3 and sent me a new 4th. Not saying you should do that but if you eliminate everything else it might be something g to consider.

 

Hey Jakuku,

Thanks for your replies. I just performed a compression test, hot and according to this thread here.

Numbers were as follows
Cyl 1: 142psi
Cyl 2: 148psi
Cyl 3: 153psi
Cyl 4: 153psi

So there is an 11psi difference between cyl 1 and 3-4, but not too bad.

Compression isn't the highest, but not anything that raises any flags to me personally.

I'm going to get the smoke test tomorrow and see how it does.

In the meantime, can you suggest any way of testing the injectors that does not require removal of fuel rail? It would be nice to take those out of the equation.

 

That compression looks pretty decent. FWIW on mine, the cylinder with the bad injector actually had the highest compression out of all. I don’t know how to determine if an injector is bad or not other than sending it off to the specialists. My guess is to just factor in the age/mileage. If it’s real high, maybe chances are theyre worn out. When you send em to be serviced at LCE, they replace the small parts inside, clean em up, and stuff. Cheaper than buying a full new set. I’d rule out the rest of the possibilities before going that route.

What codes are still persisting?

Did you try swapping coils to see if the misfire moved? Check to see if a plug wire is giving spark?

What is the mileage btw?

 

And when you did your test, did the compression hold or did it drop rapidly?

 

The tests on my truck here for comparison

 

Jakuku,

Thanks again for your replies.

The only code persisting are the P0100 P0110 P0300 and P0303 codes. The first two are only because I am disconnecting the MAF to get to the coils.

I just replaced each of the coils and sparks less than a week ago. It couldn't be those right?

Mileage is 183k. So it's up there...

Removing the fuel rail shouldn't be too complicated right? I can just take off the throttle body and the fuel rail will be able to come out? Or is it more involved than that???

Compression held with no drop. Thankfully... Was a bit worried about that one.

Thanks!

 

I followed the Hanes manual method and removed the upper intake plenum with the TB still attached. You have two coolant hoses running into the TB that will need to be capped off. A couple plugs on the backside (3?). Two bolts hold the fuel rail on. Be sure to release the fuel pressure before disconnecting. Pull fuel rail straight up with injectors attached. Pull injectors strait out of the rail. Watch the metal washers on the fuel line connection to the rail. Don’t lose em. Try not to spill gas everywhere. It’s not much of an additional step to remove the lower intake manifold to get at the fuel filter and replace that while your in there. That is if you decide to go that route. Expect injectors to take a couple weeks to be returned.

Caveat: I’m not a pro here and I’m sad I’m the only one giving advice on this at the moment. I can’t guarantee my advice is actually any good. Just sharing my experience.

Might be worth checking that your maf sensor and air temp sensor are getting an electrical signal when everything is plugged in. TBH none of those codes seems to me like they’d have anything to do with your evap canister.

 

You do a leakdown test?

 

Hi HondaGM,

Thanks for your reply.

No I did not. I don't have the test kit. I'll look into it.

Jakuku,

I appreciate the help. I'm off work until the 28th, so I might just decide to buy a new injector(s) for cyl 3(1,2, and 4). I just wish there was some easy way to prove injector was the issue first. Hopefully job is not too difficult; its pretty tight in there.

Thanks!

 

From what I’ve heard. Any aftermarket ones are not to be trusted. One of the things you should stick to OEM for. Yours are the pink ones? Go slow with the bolts. It sucks to strip any. Ask me how I know lol

 

Parts store injectors, sure, but not all after market parts are equal. Denso, for example, parts are pretty safe to go with. MotorWest Performance sells a very reasonable "upgrade" kit for both the 2.7l and 3.4l. https://motorwestperformance.com/product/tr3010-4pack-l2/ You can't go wrong there.

 

Good to see someone come in and set me straight. Good to know.

 

No setting straight necessary, you had everything covered. Just peppering in help.

 

Toyota Tacoma 2.4 2RZ, 2.7 3RZ, 4-Runner (CA Only) OE Replacement Fuel Injectors (fiveomotorsport.com)

 

Thanks a lot guys for the injector info.

I have removed all 4 injectors and I want to test them before buying new. If they spray fine then I think I will just replace the rubber rings. Any recommendations where to purchase those?

Thanks!

 

Part numbers on this page: FUEL INJECTION SYSTEM. 2003 Toyota Tacoma Xtracab 2.7L M/T 4WD | Toyota Parts Center Online

Don't know how to go about testing yourself though.

 

If you kept track of which injectors came out of which cylinders put them back in different cylinders. If the misfire code changes cylinders you know you have a bad injector.