Fuel injectors cleaning

[Breeze1]

Since the topic was raised in another one of my posts (https://www.bimmerforums.com/forum/s...hing-equipment ) and I have made some research on it, here is an interesting write up I found:

https://www.injectorrx.com/fuel-inje...aning-methods/

It was written by an "injectors service shop" (for lack of better words) so one could think that it's somewhat biased, but I honestly don't think it is because everything seems to make perfect sense...

[ross1]

Sort of interesting, nothing surprising.
Fuel injector cleaning fuel additives are intended as a maintenance treatment not a cure.
Anytime you are pushing dirt forward through the system as all the methods aside ultrasonic do you risk making things worse. The spray ports are the smallest orifices in the fuel system and that is where any filth forced through will eventually lodge.
A bottle of Techron every few fill ups will keep things clean but not cure a "bad" injector once things have gone south.
Proper cleaning services are inexpensive enough that there is no reason to fool around with any other methods. Many will provide you a "new" core if one of yours is a dud too.

[Breeze1]

Exactly: it makes perfect sense when you think about it. But in my case, although I knew that fuel additives were not "miraculous" products by any means, I learned that using them could even result in engine failure.

As I've recently begun familiarizing myself with engine management rules and the dangers of running lean, I appreciate the fact that I can know picture what would happen inside the combustion chamber because of a severly clogged injector. And eventhough I'm still miles away from being able to tune engine tables, I can also see how having a perfectly clean and balanced fuel injection system is a must before getting any kind of improvement from the stock tables.

[MarcoZandrini]

This is why it’s important to buy only top tier gas. The TopTierGas cleaning standard was jointly developed by BMW and other manufacturers. Go to www.toptiergas.com to read all about it. I pulled the injectors in my 2001 330Ci as I thought I had an injector o-ring leak. The bizness end of each injector was pristine. I had bought only top tier gas for the car during its 17 years of ownership. I’d never put an injector cleaner in the tank.

[Breeze1]

I only use Shell gas, which is among the list and known to be the best retailer in Morocco, but I don't know if the gas they offer here meets the same standards as in the US.
If that is an indication of that, when my last engine blew up we found that the valves were pristine

[ross1]

This is why it’s important to buy only top tier gas. The TopTierGas cleaning standard was jointly developed by BMW and other manufacturers. Go to www.toptiergas.com to read all about it. I pulled the injectors in my 2001 330Ci as I thought I had an injector o-ring leak. The bizness end of each injector was pristine. I had bought only top tier gas for the car during its 17 years of ownership. I’d never put an injector cleaner in the tank.

That's pretty good testimony.

[bmwdirtracer]

Until the injectors are sent to RC Injection or Marren, for a specific before and after report on each injector, there's no data. Every set of injectors I've sent out showed at least a 20% differential....with no codes. But that 20+% is certainly destructive.

While shellac and cheap gas certainly cause injector performance issues, and top tier gas helps prevent this build-up, pretending that good gas is a cure-all isn't realistic. Injector ultrasonic cleaning / blueprinting, and before / after testing is the best bargain in the automotive world.

[02Pilot]

Chris, how would you describe the practical benefits of injector blueprinting? I understand the theoretical desirability of equalizing the cylinders in every possible way, but what is the real-world before and after? Is there a noticeable change in power? Smoothness? Fuel economy?

[bmwdirtracer]

Let's acknowledge that the "butt dyno" is a primitive and inaccurate device. We all know that when we add a cone filter, or loud exhaust, the world thinks the car is faster.

I just sent a copy of a recent injector service report from RC, for an E34 M5 I'm working on, to myself. I intended to publish it here. Unfortunately, the forum has suddenly decided it can't accept any pictures larger than about 50Kb, which doesn't permit ANY pictures, because every file is too large.

Hopefully, the powers that be will fix this.

Meanwhile, this particular car had a 25% differential between injectors: which means that at least one cylinder was running 25% lean....and other cylinders would have been running RICH, because the O2 sensor was telling the DME that there was too much oxygen.

So now, you've got some cylinders being fuel-washed, and one poor piston having a hole burned in it by grossly lean mixtures. That can't be good. At this point, I submit that there's nothing "theoretical" about it....we're killing the engine.

I'll be glad to email anyone here this report, so you can see the immense difference.....just PM me with your email address.

[bmwdirtracer]

Let's try again, since we've now got people working on this: (Thank you Mr. Moderator! This one worked, I'll now go back and try the other picture, on a different thread...I think you'll recognize that picture!)

[Breeze1]

Basically a 13% increase in HP accross the BSFC listed points. So for say a 200HP initial output we're looking at a result of 226hp. And for those who get into ECU tuning God knows how much additional HP can be obtained over "non blueprinted" injectors, as far as AFR's and ignition timing are concerned.
Not bad at all!!

[bmwdirtracer]

I'd like to mention that I pointed out the "image attachment" problem to our Moderator, at an hour way earlier than reasonable, in his time zone. And it was fixed, probably before he'd finished his morning coffee.

I'd raise a cup of Kenya Peaberry dark roast to you, kind sir, but it's later here, and I've switched to beer.

[02Pilot]

It's pretty clear from that report that there's a major difference. Have you seen similar differences in newer injectors (E34 injectors have to be at least 20 years old at this point)? If so, I may have to consider pulling the injectors out of my now nine year-old, 117k-mile 128i.

[bmwdirtracer]

I sent my '01 M5's injectors off to RC, when I installed the replacement 65k engine. (The injectors were from the replacement engine, actually an '02)

The results were similar. I meant to look for the report today, but got too busy. As I recall, they had well over 20% differential between injectors.

- - - Updated - - -

By the way, Breeze, I mailed the injectors to RC Injection today, with all your information.

[Breeze1]

I sent my '01 M5's injectors off to RC, when I installed the replacement 65k engine. (The injectors were from the replacement engine, actually an '02)

The results were similar. I meant to look for the report today, but got too busy. As I recall, they had well over 20% differential between injectors.

- - - Updated - - -

By the way, Breeze, I mailed the injectors to RC Injection today, with all your information.

I appreciate that a lot Chris! Will remember it each time I go WOT

[bmwdirtracer]

The part number does correspond back to your car, by the way; I checked. I went with a slightly later set, that have polished stainless bodies with black above, rather than the slightly earlier ones which are all black. Again, they are exactly the same part number, also Siemens, of course. (You can see the 7-digit BMW part number on the top / side of the plug area, and cross-reference it at realoem for every car it's used on.)

[Breeze1]

The part number does correspond back to your car, by the way; I checked. I went with a slightly later set, that have polished stainless bodies with black above, rather than the slightly earlier ones which are all black. Again, they are exactly the same part number, also Siemens, of course. (You can see the 7-digit BMW part number on the top / side of the plug area, and cross-reference it at realoem for every car it's used on.)

Can't wait to have them on! Will throw in a new filter at the same time and regularly use a cleaning additive to keep them clean. The only thing I'm not sure about is how do I know there won't be some dirt clogging them even if the filter is new, like something coming from the tank for e.g. Or maybe using only good quality Shell fuel with "built in" detergents will be enough?

[bmwdirtracer]

Detergents and additives can't clean dirt; they prevent varnish-like buildup. A good filter prevents dirt (factory / OEM is best). Quality fuel, bought from a modern station, preferably one that pumps a lot of gas, is your best bet. Never buy gas when the tanker truck is delivering it.

Any more than that, don't sweat it.

[ross1]

"Blueprinting"
My understanding is that this style injector is not serviceable beyond replacing the exterior parts, screens pintle cap and sealing rings.
I believe "matching" is all they do and this would require a stock on hand or deliberately restricting somehow to achieve the desired result.
I stand to be corrected.
I did a brief stint in a diesel injection shop as a yoot. Those were mechanical, operated solely be fuel pressure and WERE rebuildable although it was not very common practice at the time. VERY precise angles needed to be ground onto the needles and seats. I was the guy testing and examining the duds on an optical comparator.
No way is anyone dismantling our injectors and correcting the needle and seat for anywhere near the typical fees.

- - - Updated - - -

. Never buy gas when the tanker truck is delivering it.

.

Why not?

[MIKYZZ4]

Why not?

Common sense really,as all the debris particles,sediment,rust,etc., that have all nicely settled at the bottom of the tank-undisturbed,
are now being churned up by the fresh fuel being pumped into the tank,
now evenly suspended in the fresh fuel,
until time and gravity return them to settle at the bottom of the tank.

[Breeze1]

"Blueprinting"
My understanding is that this style injector is not serviceable beyond replacing the exterior parts, screens pintle cap and sealing rings.
I believe "matching" is all they do and this would require a stock on hand or deliberately restricting somehow to achieve the desired result.
I stand to be corrected.
I did a brief stint in a diesel injection shop as a yoot. Those were mechanical, operated solely be fuel pressure and WERE rebuildable although it was not very common practice at the time. VERY precise angles needed to be ground onto the needles and seats. I was the guy testing and examining the duds on an optical comparator.
No way is anyone dismantling our injectors and correcting the needle and seat for anywhere near the typical fees.

- - - Updated - - -


Why not?

I think "blueprinting", here, refers to a cleaning service + delivery of a before/after fuel flowing report for each injector.

There doesn't seem to be any restricting involved: if bmwdirtracer (or "the Moderator" ) can confirm that the report he shared is not the one from the E34M5 he intended to share initially but rather one from a 200hp "ish" 6 cyl engine, the results are in line with what is expected: [(200hp × .5 bsfc)/(6 cyl×.8 duty cycle)]= 20.8 lbs/min x 10.5 = 219cc/min.

[MIKYZZ4]

"Blueprinting"
My understanding is that this style injector is not serviceable beyond replacing the exterior parts, screens pintle cap and sealing rings.
I believe "matching" is all they do and this would require a stock on hand or deliberately restricting somehow to achieve the desired result.
I stand to be corrected.
I did a brief stint in a diesel injection shop as a yoot. Those were mechanical, operated solely be fuel pressure and WERE rebuildable although it was not very common practice at the time. VERY precise angles needed to be ground onto the needles and seats. I was the guy testing and examining the duds on an optical comparator.
No way is anyone dismantling our injectors and correcting the needle and seat for anywhere near the typical fees.

Read this from their website, scroll down to the bottom:https://www.rcfuelinjection.com/History

[MauiM3Mania]

.....if bmwdirtracer (or "the Moderator" ) can confirm that the report he shared is not the one from the E34M5 he intended to share initially but rather one from a 200hp "ish" 6 cyl engine,....

Keep me out this! LOL I have no control over what people upload/link to.

[Breeze1]

Keep me out this! LOL I have no control over what people upload/link to.

Fair enough, I was just kidding a bit

[bmwdirtracer]

From RCI:

Fuel Injector Standard Service

Fuel injectors cleaned, balanced and calibrated
Returned in 24 hours* with a completely detailed, computerized summary

The purpose of cleaning and flow-testing is to 1) remove any contaminants inside or outside the injector that impede fuel flow or degrade fuel spray pattern 2) to accurately measure each injector's fuel flow ability and 3) acquire quantitative data on injector performance the vehicle owner can use in matching injectors or tuning the engine's fuel system.

Any set of fuel injectors will benefit from RC's cleaning and flow analysis service, This is even true of new injectors because the individual-injector and system-total fuel flows must be known for performance tuning purposes. It is not uncommon for a set of original equipment (OE) injectors to have an unacceptably wide range of fuel flow and it's possible to even have new injectors that do not function properly. RC's standard testing process identifies those problematic injectors.

The test process is as follows: first, your injectors are installed on RC's custom designed and built computer-controlled injector flow-testing equipment. A non-flammable, (gasoline-like) test calibration fluid is pumped at a precisely-controlled pressure through the injectors while they are pulsed by injector-drivers built into the equipment. The volume of fuel passed through the injector is accurately measured for a set amount of time and from those figures, fuel flow is derived. During the flow- test, the injector spray patterns are visually inspected and analyzed by RC's technicians using both bright room and strobe lights.

After the initial flow-test, your injectors are transferred to an ultrasonic cleaning machine and connected to injector drivers. They are submerged in cleaning solution and pulsed while being subjected to ultrasonic waves. The combination of the cleaning solution and the ultrasonic waves aggressively clean the internal and external parts of the injectors.

Finally, the now-clean injectors are reinstalled on the flow-tester and run again. At the conclusion of the test, a printed report is produced. This report lists: fuel flow rates (in pounds-per-hour and cubic centimeters per minute) before and after cleaning, and spray pattern assessments for each injector tested. Also included is the "system balance" number which is the flow difference, expressed in a percentage, between the injectors having the highest and lowest flow rates amongst the lot of injectors tested. The system's total fuel delivery in lbs/hr. and cc/min along with a computation of potential horsepower at three different brake specific fuel consumption rates concludes the report.

* We strive for a 24 hour turn around for most fuel injector servicing. However, there are times when our volume may dictate a 48 hour turn around. Holidays and weekends are excluded. If overnight shipping is used, the turnaround time is usually three days. RC is not responsible for delays by the shipping companies.