Hello:
I have been experimenting with Chevron fuel injector cleaner on
my 4 cyl 97 4Runner. I have used 2 different products:

[1] Chevron Techron Concentrate Plus Fuel System Cleaner. This supposed
to clean injectors, intake valves, ports & combustion chamber. It can
only be used every 3000 miles

[2] Chevron Pro-Guard Fuel Injector Cleaner. This is supposed to only
clean fuel injectors and can be used every 1000 miles.


Whenever i used any of the above product, I always used it when the
gas tank is almost empty, then I fill the tank with approximately 10
gallons of gas. Here are the results:

Using product [1] above, the engine stops knocking. In fact my freeway
mpg jumps by around 2 to 3 MPG. This is amazing. I actually noticed
that even after the car has been driven more than 3000 miles since
I added this product to my gas tank.

Using product [2] however gives me different result. The engine knocks
very easily, especially when driven from a stand still. As soon as the
engine picks up load, it starts to knock.

So my questions are:

What is going on here. Does the product [1] contains chemical that
boost the octane? Which product should I continue to use without harming
the engine? (yes product [1] is more expensive). Any other good suggestion
or explanation appreciated.

Regards,
Jim

 

Techron is pure Techron concentrate, which is the absolute best fuel additive money can buy. Thats why you should only use Chevron, Shell and Texaco fuels (all have Techron/similar additive) and supplement with the Techron concentrate a few times a year.

Proguard is a very diluted Techron, cut with alcohol (like HEET) to make the price more appealing to those that don't know any better. Because of the alcohol, it's able to mix the water in your fuel tank with gas, which may explain your knocking.

 

The Techron concentrate is the real deal. The others are a waste of $$.

 

hmmm i may just have to give this stuff a try

 

I bought a package of "pro-guard" from costco 4 bottles for $9 and i feel its a total waste of bull.

I feel the only real deal fuel cleaner, are techrol concentrate, BG44k and redline fuel cleaner.

 

i use the lucas stuff

 

Tecron is a great product but I would use it sparingly
Why?
I know from experience

Sounds like you have a "Spark" issue as opposed to a "fuel" issue

Reason # 1 Spark plugs
I personally have fouled out older plugs with techron ("older" is ANY standard 4runner plug with over 30K) I used techron fuel injector cleaner with an empty tank and drove 10 miles to the gas station to fill up as it indicates on the bottle. The only issue was that I drove it 10 miles to long......
I should of added it at the gas station!!!
BIG MISTAKE
knocking pinging loss of power ect....
I really wanted to puke, as I thought I trashed my injector seals...

I produced the exact same symptoms you have... knocking, loss of power. You may have put the last nail in the coffin on your sparkplugs.... pull them out and see if they look bad. (wide/worn/rounded electrodes and fouled out)

Reason #2 Injector seals
material can be damaged by harsh additives. Just don't go too crazy with that stuff. Every once in a while is ok but every 1000K is far too much. Today's fuels have plenty of cleaning additives(as required By law) especially if you are using "top tier" fuel which is ANY grade (87,90,93) by BP or Shell.
Chevron fuel does sounds great but we do not have any chevron stations around here.


I'm 95% sure it's your plugs. Remember 30,000 miles is close to max for standard 4 runner plugs. AND remember DUEL ELECTRODE PLUGS ARE REQUIRED FOR THE 3.4 ENGINE (it says so right on the engine)

BTW my plugs had 78K before I trashed them with chevron techron
Once they the plugs were replaced I could not believe the power difference at accelaration and idle .....AND NO KNOCKING.
good luck and please tell us what you find
enjoy

 

I'm not so sure about the 30,000 being the lifespan of the plugs. Mine went bad @ 139,000. And yes they were the original plugs and wires. And the tech at the dealer said they last on average about 100k.

 

i got a bottle and my truck is empty soo will see if it helps i user chevron gas anyways since its only a few cents more than the cheaper gas

 

Marsallmay,
You do have a good point but in my opinion, the tech at Toyota who said the "standard" duel electrode plugs could go for 100K was wrong.
.....at least mostly wrong....
Read on brother.
You make a good point and one can go well over 30K miles on their standard plugs (as I did) and the car will work fine......
for awhile....
However, I'm willing to bet good money that the performance of the engine will degrade to a measurable amount over time with older plugs. Personally, I do not try to over think the Toyota engineers (too much) as they are a lot smarter than me and they probably know performance will suffer if you leave older plugs in the car.

FACT: Toyota is very exact (and honest) with their recommendations and their recommended tolerances (spark plug life and gaps) are VERY Specific. Bottom line, is that they test their engines for all sorts of things. AND Especially for a specific plug life spans.
Through basic engine testing they know exactly how their engines will perform at 30K 40K 50K 90K ect with the original plugs.

They know what people will likely do with their cars (deferred maintenance, abusive driving ect.... )
they know all of this, before people even own the car. Do we all remember what the "Toyota engine slugging" issue was from??. It happened because some of those people were not CHANGING THEIR OIL Very often!!

And Skipping oil changes with a Conventional "dino" oil in a high miliage engine, with depostits, varnish build up, is a death sentance for the engine as the small oil path ways will get
"sludged"
....kind of like heart disease where arteries become clogged up with fatty deposits.... and here comes the attack.

So because of those "ill informed people" Toyota had to Over engineer their engines to avoid the "Ignorance FACTOR"

Truely, I learned that they say 30K for their standard plugs for a soild reason.
Dude, I bet the stand plugs will last a good 50K with good fuel, without a huge difference in performance, but not much longer. Then and Add 1 bad tank of gas and those 50K plugs are screwed.
Case in point: take a look at what a standard duel electrode NGK/Denso spark plug looks like after
80K miles? Seriously, they look awlful!

The plug gap is doubled in size due to conductor loss. Bottom line, larger spark plug gaps start to mess with engine Horse power, engine timing, fuel economy, poor ignition (half assed explosions) and overall performance will suffer not to mention the adjustments the computer will have to make.....

Moreover, the plugs are usually fouled, discolored and sometimes the engine will knock because of this. Then add concentrated fuel injector cleaner to aged plugs with 80K on them (as I did) and the plugs will foul out. And then knocking and pinging begins!!!
Experience has always taught me best ....And I wish I had listened and learned from the mistakes others have made more..
I'm still learning every day

 

My original plugs have been changed at 60k intervals and when i changed mine at 120k there was no noticeable increase of performance or MPGs. I use the 44K once a year and I average about 17mpg around town and I have a bit of a leadfoot.

 

Well I guess you could compare spark plug wear to shock absorber wear. The wear is so gradual that you can't really tell until it's completely worn out.

 

Dirty injectors is what the problem is. I use this stuff called FP60 every fill up that lubercates the entire fuel system and upper cylinders and also cleans well. 3oz is all it takes...so no you will not hurt your engine.

 

I've heard Chevron Concentrate is best of the best. It's got "PEA" that most other additives don't have. But honestly, the $2.12 for Berryman's B-12 CHEMTOOL has me sold.

Wait til a low tank of fuel, add half the can at the pump, pump about half a tank of fuel, then add the rest of the bottle. Can says it treats 30 gallons of fuel, or 1 fl. oz. per gallon of fuel.

Kinda strange, but I got my first CEL EVER- using Chevron concentrated Complete Fuel System cleaner. Followed the directions to the T. Took the tank way low past the E. Dumped in the bottle, filled up with 16 gallons of fuel as per the bottle directions, drove around as normal.

I don't drive much though, but halfway through the tank, something triggered a CEL. But on my way to advance I "gunned it" (WOT) on the merge/acceleration lane, and off went the CEL So I never did get it scanned

Berryman's is good every 5K the can says. And as another poster mentioned Toulene/Xylene above, that's exactly what B-12 CHEMTOOL is. Like a molotov cocktail of Acetone, Toulene, Xylene, and methanol - not sure of the exact concentrations off hand though

 

Miget96, NICE!!!! And GOD BLESS AMERICA.

 

i add the techron @ 1/2 dose at 7500 mi oil changes.
never had issues.

just passed 200,000 mi last week

the last 2 sets of NGK's i used got changed at ~55K +
both electrode sets were oval and the gap was causing a miss in 2 cyl. last time.

the next change will be done before 50k