Fuel cleaners

[brad dryden]

I have heard both good and bad about using fuel injector cleaners and such and was wondering if their was one brand particular that stood out the best over others and how ofter would some one really need to use it?

[LETMGROW]

There are a lot of different brands out there for sure. I have used quite a few different ones but can't really say one is any better than the other.

One thing I will never do is to pour a can of cleaner in a gas tank without changing the fuel filter first. The last thing I would want to do, would be to loosen any dirt trapped in a filter and send it to the fuel rail and injectors.

This would defeat the purpose of a cleaner entirely. Also if the tank had some debris in it, the filter would have full capacity to filter and trap it.

I also use cleaner sparingly. Too much can shock the system Especially if your vehicle is designed to handle Ethanol fuel.[ Flex-Fuel ]

I add about 1 can every 5 or 6 tanks of gas. I change my fuel filter every fall irregardless of mfg. maintenance recommendations.

Lynn

[Shaun_300]

I think the best one is the kind where you pour the cleaner into the canister, you hook it up to your schrader valve at the fuel rail, can gets pressurized to 55psi or whatever the fuel pressure specs are, pull the fuel pump relay and run the vehicle purely on the injector cleaner until the can runs out. Of course this has to be done in a shop that has this equipment. The injector cleaner you buy in the stores definitely doesn't hurt either. But like Lynn said make sure your fuel filter is fairly new. We also do a service at our dealership called a fuel/air induction service. Same idea as I stated above but the cleaner sprays into the throttle body when the engine is running to clean the intake side, cleans all the crap out of the intake, behind the valves in the cylinder heads, tops of the pistons etc. Then a can of injector cleaner comes in the kit that goes in the tank. This service is awesome. You can feel the difference in throttle response and engine performance like night and day, especially on a higher mileage engine. Lots of customers come back in awe of how much difference it really makes!

[LETMGROW]

The method Shaun describes is by far the better option.

Problem here is GM puts test ports on all their vehicles [ except some of the older TBI systems] Chrysler and Ford didn't. These systems require in line adapters into the fuel line. These adapters are not cheap. This puts the job out of reach of the do it yourselfer and even some smaller repair shops that don't do a high volume tune up business.

This is why most shops get a pretty good $ to do the cleaning.

The same holds true just to check fuel pressure during a diagnosis. There is no industry rule or standard here.

If a DIY wants to do the cleaning service he would be well advised to make sure he can hook the cannister up before he buys the kit and takes it out of the package.

Also there are more and more vehicles being built without external fuel filters. The have only large [ Lifetime ] filters in the gas tank hooked to the fuel pump module. Many of these aren't even replaceable. Even if they are, they require tank removal.

Lynn

[Shaun_300]

All 2005ish and newer GM vehicles do not have an external fuel filter. Only ones that do are the Cobalts and Corvettes, where the fuel pressure regulator is actually inside the fuel filter. Everything else is in the tank.

[brad dryden]

How much would you be looking at to run pure injector cleaner through your system? I know shops are different on prices but just wondering what kinda prices their are.

[Shaun_300]

Probably in the neighborhood of $100-150.

[redkneck]

I miss the old TBI setup. Seemed a lot easier to maintain.

[Shaun_300]

Yeah, but the TBI sure robbed the power! Especially in the late 80s early 90s trucks. Truck with a 5.7L 350 had a 150-175hp. Now even with a 5.3L you're 315hp and get double the MPGs.

[LETMGROW]

I miss the old TBI setup. Seemed a lot easier to maintain.

The TBI systems were simpler but no where as efficient as the newer systems. You were basicly limited to a 1 or 2 barrel carb. flow system except for the crossfire Corvette which used 2 TBI units which were a pain to keep syncronized.

The new systems use a myriad of sensors to keep the air fuel ratio at the optimum 14.7:1 fuel to air ratio. The computers are very fast updating, the air flow is accurately measured through a Mass air flow sensor etc. No doubt there is more to consider when diagnosing a problem, but when they work correctly they are much more efficient.

What's in store? Who knows! We are only on the brink of technology for better tailpipe emission and fuel mileage.

If only clean fuel is put into the tank there are really no great problems with the injectors themselves. Generally it is a signal to the computer from a faulty sensor which gives the impression an injector is bad.

Case in point: I had a vehicle in my shop a short while back which had had two complete sets of injectors replaced by two different shops. A quick scan of the data showed the coolant temperature sensor was telling the computer the engine was running at 130 f when it was actually running at 198 f. Not enough to set a check engine light, but the tailpipe was black, vehicle had little power and mileage was tanked. The other shops thought all 8 injectors were sticking open! Guess they never tried an injector balance test. I replaced the CTS, rechecked the data. WA HOO! Done, gone! Total bill under $100. Made a new friend.

Diagnosis today depends on one thing. You have to know how something works to properly diagnose a problem. The little $49.00 code readers out there have cost consumers millions because the guy using it doesn't really know how to interperate the information. Got a code for a bad o2 sensor? Maybe it is bad. Maybe though you have a small exhaust leak upstream of the sensor. You can put all the sensors ever made in the vehicle and there is that check engine light back on. Same code again. The same holds true for a small vacuum leak or a sticking injector. Some cars even have seperate fuses for o2 sensors. I'm not even going to tell you my story on this one!

I have strayed from the topic a little, but I still think the newer systems are better, but no doubt tougher to figure out.