Fuel Induction Cleaning Service

Hey all. I took my truck to a muffler shop recently and they tried to sell me on a fuel induction cleaning service. I guess it’s like a high priced commercial version of sea foam. They said it’ll clean everything including the throttle body and make the truck run a lot better. Anybody tried this? What are your thoughts? Thanks!

 

Unless your truck is running bad now, it won’t make it run a lot better.
Keep your money, it’s not needed.

 

That service applies more to pure direct-injection engines, in which crap tends to build up around the intake valves (before the cyclinder) because there is no constant wash-down of gasoline (which is a pretty good solvent / cleaner).

But your 2nd gen 2009 is a port-injected engine design, in which the fuel is sprayed into the intake ports upstream (outside of) the combustion chamber. It's uncommon for a port-injected engine to suffer from severe gunk build-up in the intake runners/ports. So, very unlikely to be needed for your engine.

The 3rd gen Taco engine has a dual injection design: is has both port and direct injection. At the cost of more complexity & build cost, having both allows direct injection to give optimal fuel burn, while also preserving the ability to clean & wash-down the intake ports with periodic bursts of plain port injection.

Mr. SavageGeese explains in more detail why pure direct injection engines tend to need periodic & expensive port cleanings:
https://www.youtube.com/watch?v=xrLNDgrIw3U

 

It’s idling poorly and stuttering a bit. I was going to either due the service or clean the throttle body myself.

 

Never hurts to have a clean throttle body. That's a pretty easy DIY job.

The next 3 things I would do after that are:

• Check & if need be replace the engine air filter.

• Change the oil if it is over 5-6K miles or 1 year old.

• Clean the MAF sensor. (Read or watch vids on how to do this properly if you aren't already familiar.) Disconnect the battery for at least 15 mins. After doing this, drive at least 150-200 miles or so at varying speeds to allow the engine to re-learn/re-map fuel trims.**

**NB: battery disconnect to reset the ECU only works on 1st or 2nd gen Tacos. 3rd gen ECUs do not reset fuel trims when power is disconnected.

Or if you're feeling more scientific you can read up on & use the official Toyota procedure to accomplish that more quickly. (Needs a scan tool.)

If that doesn't fix it, then check & if significantly worn or burned/fouled-looking, replace the sparkplugs. (If burned/fouled, that likely indicates some deeper cause that needs to be tracked down as well.)

If it's still not idling smoothly, then move on to looking for these possible causes:

• Vacuum system leaks due to damaged or disconnected hoses.
• Constriction or malfunction (stuck open or closed, depending on the valve) on any of these: EGR, PCV, or in the EVAP system. (Basically a sub-class of vaccuum leaks.)

These are much more likely in older or harshly-treated/poorly-maintained engines, >100K miles:

• One or more dirty or out-of-spec fuel injectors causing misfires. Attempt to clean & test the injectors, either on or off the vehicle.
• Badly worn/out of spec timing chain.

• Unbalanced compression, i.e. 1 or more cyclinders has much less compression than others. (Usually about 10 PSI difference between cyclinders is within manufacturer spec, 15-20 PSI or greater difference is not good.) Most likely cause would be a head gasket issue but it could also be valves failing to seat properly in just the affected cylinder. Severe sidewall damage to just the affected pistons could also cause it. Diagnosing compression can be a little tricky, google or youtube search for "relative compression test" (diagnosing cylinder compression indirectly using an electrical current waveform) as an alternative or additional test to do alongside a traditional sparkplug-out gauge compression test.

https://www.youtube.com/watch?v=0P0CPRFLmww

 

When were the plugs changed last?

Cleaning the MAF and changing the plugs would be a good idea?

One of the first things that show up on worn plugs in the 4.0 is a “rough” idle.
It will run just fine off of idle, and while driving, but the idle won’t be very smooth when the plugs wear.

 

Fwiw they’re probably trying to sell you this BG product. In my opinion, not worth it. I would do what others have said before spending your money on this.

 

Thanks! I cleaned the throttle body and will move onto the plugs. They haven’t been changed in at least 30k.

 

Thanks again for this awesome write up. I dislocated my shoulder so I can only manage the passenger side spark plugs at the moment. Do you think it’s worth doing only 3 right now?

 

I wouldn't change only 1 bank of spark plugs. Ideally all 6 cyclinders should produce as-close-as-possible to the same amount of force & power.

With new sparks on one side & old on the other I'd be concerned that the bank with new sparks is burning cleaner and faster producing more power than the other bank. Unbalanced power output might exacerbate rough running & unwanted vibration. Of course this depends a lot on how old/bad the original sparks are. The greater the difference the more the power imbalance & the more serious the concern.

 

Ok. Thanks