Fuel Injectror Cleaner

2 choices - the Toyota brand stuff sold at dealers and Chevron Techron. Follow the instructions carefully, use up the fuel in the tank within a week.

I prefer the Chevron Techron Clean-up Product for engines that actually need a cleaning (see

). "Chevron PRO-GARD® Clean-Up Engine Deposit Remover

"Removes deposits from fuel injectors and intake valves in one tankful. Fights knocking and pinging by reducing the harmful effects of combustion chamber deposits. Safe for use every 3,000 miles to keep your engine clean."

Any particular symptom, or do you just have a feeling? I used to be a big fan of the Techron Products, but in the last few years (since say 1998), I don't feel they have been needed as much, at least in my area. But then I have mostly been buying name brand gasoline (usually either Shell, Texaco, Amoco, or Citgo). I definitely could tell a difference (mostly in starting ease) in the early to mid 90's when I used the Techron product in my older (but fuel injected) truck. I still occasionally add Techron to my vehicles but, I can't really detect any improvement. So it may still be useful, but I am just not getting a dramatic improvement.

Ed

Ever think that it's maybe due to the fact that you're older and less impressionable now?

Well maybe, but you would think if it really was beneficial I would see an improvement in gas mileage (I keep records for all my cars). I think that engines and fuels have made steady improvement. Clearly things aren't perfect since GM has pushed for the identification of top tier fuels that supposedly have superior properties.

Ed

Well, you're likely right Ed, I didn't know that you keep good records. Guess I'm not as keen as you. I was just going by kids that I see here who say "hey!...I tried a tankful of high test gas today and WHAT a DIFFERENCE!...the POWER!...the PERFORMANCE!...

Yeh...

Re: Fuel Injectror Cleaner

Group: alt.autos.toyota Date: Tue, Sep 20, 2005, 6:24pm (EDT+4) From: "C. E. White" wrote: I prefer the Chevron Techron Clean-up Product for engines that actually need a cleaning (see

"Chevron PRO-GARD® Clean-Up Engine Deposit Remover "Removes deposits from fuel injectors and intake valves in one tankful. Fights knocking and pinging by reducing the harmful effects of combustion chamber deposits. Safe for use every 3,000 miles to keep your engine clean." Any particular symptom, or do you just have a feeling? I used to be a big fan of the Techron Products, but in the last few years (since say

1998), I don't feel they have been needed as much, at least in my area. But then I have mostly been buying name brand gasoline (usually either Shell, Texaco, Amoco, or Citgo). I definitely could tell a difference (mostly in starting ease) in the early to mid 90's when I used the Techron product in my older (but fuel injected) truck. I still occasionally add Techron to my vehicles but, I can't really detect any improvement. So it may still be useful, but I am just not getting a dramatic improvement. Ed

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Thanks I'll try that.

At start up on occasion , I'm having problems at start up , that feel like the engine is choking. Air filter is new so it is not for lack of air. At 90k miles the next thing I thought of was semi-blocked injectors.

I use BP gas. CP

----------------------- BP gas should have fuel additives that prevent fuel injectors from gumming up. If the fuel injector cleaner doesn't work, you can have the injectors professionally cleaned at some shops. If the injector spray pattern is OK, here's some other things to check:

Have a shop install a fuel pressure gauge and monitor the pressure at start-up. If it is too low, the fuel pressure regulator may be bleeding down overnight.

Depending on the model and year, check the cold start injector and cold start injector timer circuits.

Depending on the model and year, check the MAF sensor for buildup on the hot wire.

EPA rules require all unleaded gas sold in the US to have an "effective level" of fuel injection cleaner. However, not all fuel injector cleaners are created equal. I have no idea whether the cleaner in BP gas is one of the better ones.

Checking the fuel pressure is an excellent suggestion. One simple way to check for a leaky regulator, leaky check vlave, or leaky injector (all reasons for low fuel pressure at start up) is to switch the vehicle from off to run several times (3 or 4) without actually switching to start. After doing this, try starting the engine. If the vehicle engine starts quickly, it is a good indication that there is a fuel pressure problem.

MAF sensor should not affect start-up.

One other obscure possibility - Intake valve deposit build-up was a common problem on some engines (particularly GM engines). This particular problem usually shows up as hard cold starting. The deposits are pours and absorb fuel. Over a long period of time (like overnight) the absorbed fuel evaporates and the deposits dry out. If the deposits are dry, they absorb a lot of fuel that should be going into the cylinder, causing a lean condition. This causes hard starting. Eventually if you keep trying to crank the vehicle the deposits will be saturated and then the engine will start. Switching the ignition from off to run several times before switching to "start" as suggested above will also likely circumvent this condition by saturating the deposits before you actually try to start the car. The Chevron intake valve cleaner may correct this problem. In some severe cases the deposits have to be removed mechanically (GM did it by walnut shell blasting the valves with the heads still on the car).

Ed

I'm going by memory here, but I believe a Toyota electric fuel pump does not operate unless engine is turning. You will not hear the familiar hum from the pump like some U.S. domestic makes, so the on-off cycle probably won't do anything.

Oops, my bad...

Again, the on-off trick won't work on a Toyota. The walnut shell trick has been around for a long time. BMW, Ford, GM, and Toyota, to name a few, have used it. Some 80's vintage Tercels were prone to valve deposits so the dealers were shipped the shell blasting kits. I have not heard of this problem on other Toyotas.

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Indeed. You have to cycle OFF/ON/START/release without starting the engine. This dance makes the ECM run the fuel pump for 3-5 seconds while you're back in the ON position. Repeat a couple of times to charge the fuel rail.