Another Fuel Injector cleaning thread (2 Viewers)

[Kernal]

Sent out a set of high mileage original injectors (23250-74080) from a 1995 FZJ80 to Witch Hunter to be tested and ultrasonically cleaned. It's been discussed before that it might be a waste of time to send injectors out to be cleaned but as I was pulling the head I figured now was the time to do this.

My impression on this 95 FZJ80 is that the PO likely never used any sort of fuel injector cleaner based on the overall poor maintenance I found as I went through the baselining on this vehicle.

Before sending these injectors out to be cleaned I'd tried a few bottles of injector cleaner (I forget exactly, but IIRC over 1000 miles of driving I added Redline SI-1 Complete fuel system cleaner, Chevron Techron (double dose?), and the large bottle of Gumout good for up to 35 gallons. All of these were added to half a tank or less of gas except maybe the double dose of Chevron Techron.

The engine performance did improve somewhat after using the cleaners however I had also replaced the distributor cap, rotor, and air filter during the same two week time period.

Point is, even after some good in-the-tank injector cleaners the off-the-vehicle ultrasonic cleaning did help improve the function of the worst injectors. They also all Ohm'd out in spec and I wanted to be sure they were good before stuffing them back in.

Having said that, no way would I spend the hours required to pull injectors on a 1FZFE to send them out to be cleaned as a PM unless there was a specific issue with one or more of them. I'd just do what I've done with my other vehicles; more frequent use of the better in-the-tank cleaners along with regular use of a top tier gasoline. Add to that, never letting the vehicle sit for weeks, months, with Ethanol based gasoline sitting in the fuel rail; apparently water (corrosion) is the worst enemy to a fuel injector. Maybe plan to send your injectors out to be cleaned if/when the upper intake or head has to come off. IMHO/FWIW.

Looking at the Flow results below, injectors #1, #3, and #4 were in the worst shape:

 

[Irish Reiver]

I've always assumed that if in tank injector cleaners really work given its 1 bottle in 1 tank then the stuff they [Chevron, Shell, Mobil] put in their gas must be at least as good given that it is in every tank of gas.

It almost looks like your before and after data support this.

 

[baldilocks]

@Kernal - I agree with your theory. I bought an old, high mileage car. I tore into it extensively in order to, A. Learn about what I have and will be depending on for long trips and excursions far from services. B. Ensure reliability for those excursions. C. Establish a solid base line reducing variables. In other words, I know what I’ve got and it isn’t what someone else dictated.

When I did the HG on the 1994 model that I rolled 5 years ago I sent the injectors to RC engineering. 8 months later I rolled that cruiser and the engine has been in storage ever since. Last March I removed the intake and egr system for cleaning, installation of my previously purchased new engine harness and other refurbishments on the drivers side of the engine. I decided to install the injectors from my stored engine but was concerned that the fuel system may be gummed up or corroded from crappy fuel that may have lingered in the system.

I called RC engineering and they informed me that it was five years to the day since they received those injectors from me last time. They said to send them the injectors and they would do a verification of them for nothing more than the cost of shipping. That’s good business and peace of mind for me.

Some people go wheeling with groups of other cruises every time they go to the playground and that brings about a feeling of security. I find myself alone in places far from black top and have no one there to drag me out. Independence is never the cheapest choice.

 

[Kernal]

baldilocks: how did you store those injectors (left on the fuel rail, in the garage, or?) and how did they check out after sitting for five years?

 

[Kernal]

IrishReiver: I think the injector cleaners did help some as the engine felt more responsive after the first few treatments and before changing anything else to the engine. But I think also based on discussions with the people doing the injector cleaning there are sometimes very hard deposits that only the ultrasonic cleaning will remove, and the results I got seemed to show that.

I'm a fan of the fuel injector/fuel system cleaners, particularly the better ones with higher levels of PEA and use them regularly. For the rainy foggy humid times of the year I use the Red bottle of ISOHEET (Isopropyl alcohol) with every tank of gas and frequently the rest of the year to remove any water in the fuel system. However in this 95 model I picked up six months ago, it had horrible maintenance previously so everything had to be baselined.

 

[baldilocks]

Yes, the engine was removed , placed on a storage cart that I made and sat there ready to go. Then I started borrowing a few items for it.

RC engineering didn’t report any issues and charged me only for return shipping so I assume the injectors were ok.

 

[Kernal]

That's good to know as the shop that cleaned my injectors recommends installing them within 30 days so they don't dry out. However they did oil them well and put them in small zip lock bags so they'll likely be good for a long time.

 

[aclos3]

Last year I sent mine out as well since they were original to a 233,000 mile truck. The 'before' numbers showed that they were statistically quite close. Of course it was nice to have them tuned up to be ~99% consistent and cleaned with fresh seals, but in the end it wasn't necessary. I just did it because it felt like the right thing to do at the mileage and I had everything in that area pulled apart anyway.

 

[93yotasr5]

I had some issues with my injectors a few years ago. I used several different fuel system cleaners with no noticeable results. I finally removed the upper plenum and associated parts to get to the injectors. I took the injectors to “mr injector” as he was not far from me. A couple weeks later I got them back and they were in bad shape. I’ll have to find the data sheet but 2-3 of then we’re barely functioning.

once I put them back on my truck, it ran so much smoother.

 

[Shoredreamer]

I am doing a basic refresh on my engine since it’s now at 250k, and I rely on it to get me out and back when taking my family out exploring. I needed a few leaks fixed, and to test and verify more components of the sfi system, including the injectors, to try to find where my surging/hesitation I’ve had the last 9 months.

I have never run bottles of injector cleaner before and the engine has never been serviced for at least the past 150k of me owning it. Needless to say, I wanted to get my injectors serviced, so I pulled them and sent them off to RC. Got them back last Friday and definitely think it was worth it based on the stat sheet I got back.

It seems as though they weren’t in the greatest shape haha. I am hoping the cleaned and balanced injectors may help with the hesitation/loss of power I have. (I also found my VSV Evap failed ohmeter test, so that may be part too).

 

[QuackAxel]

I am doing a basic refresh on my engine since it’s now at 250k, and I rely on it to get me out and back when taking my family out exploring. I needed a few leaks fixed, and to test and verify more components of the sfi system, including the injectors, to try to find where my surging/hesitation I’ve had the last 9 months.

I have never run bottles of injector cleaner before and the engine has never been serviced for at least the past 150k of me owning it. Needless to say, I wanted to get my injectors serviced, so I pulled them and sent them off to RC. Got them back last Friday and definitely think it was worth it based on the stat sheet I got back. View attachment 2600879View attachment 2600880It seems as though they weren’t in the greatest shape haha. I am hoping the cleaned and balanced injectors may help with the hesitation/loss of power I have. (I also found my VSV Evap failed ohmeter test, so that may be part too).

I'm having hesitation and loss of power as well, I have another lower intake and injectors sitting in the shop that I'm going to send off to get cleaned.

Did it help your hesitation issue?

 

[FMC80]

My cruiser ran extremely well and acceleration was very smooth. I use fuel treatment additives every few months. I sent my injectors off to RC Fuel Injection and mine were in very poor condition. I couldn’t believe it; see my results sheet:

 

[Malleus]

What's the difference from the driver's seat?

 

[FMC80]

What's the difference from the driver's seat?

If this question is for me, my drivetrain is pulled for a new short block and HG, so I'll let you know in a couple of months!

 

[Malleus]

 

[Shoredreamer]

I'm having hesitation and loss of power as well, I have another lower intake and injectors sitting in the shop that I'm going to send off to get cleaned.

Did it help your hesitation issue?

Recalling, no the injector servicing did not help my problem. Based on most owners‘ results including mine, if you are in there, probably a good idea to do it. My specific problem was pulsing hesitation under moderate acceleration around 2200-2400 rpm’s. The culprit was my fuel pump. Replaced fuel pump and problem was instantly gone.