Alright, let's take a VOTE.. (fuel injector cleaning)

adream8

AntnyG
No, this isn't political..

It's something far more contentious!

Do I drop $150 ($30 x 5, including CSI) to have my injectors professionally cleaned with fancy ultra sonic hocus pocus..?

Or do I just do this..?


🤣

(Pretty sure I already know what the consensus is gonna be, but it'll be fun to hear the responses.)

But seriously though, if I can save the $150 for something else..

Damn pricey, these "alleged" microscopic deposits.. 😏
 

Dr.Jeff

True Classic
Actually there is a lot more to it than squirting a aerosol can of carb cleaner through them. ;)

But it will really depend on the existing condition of your injectors. I'd start by doing some testing to see how much cleaning they need. Look for flow volume and rate, spray pattern, and consistency. If they are quite good already then you might get away with the method in that video. But anything worse should be done professionally (unless you want to build a proper cleaning set up with a ultrasound machine, electronic pulser device, high pressure circulating system, the correct cleaning solution, and source some replacement internal filters). The professional service will make them perform as good as new. Also consider that a cleaning service is a lot less expensive than buying new ones, but offers the same result.
 
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adream8

AntnyG
Thanks, Dr J.

I assume you mean professionally tested?

Or is there something I can do on my own to assess their condition?

They’re not out of the car yet, but I hope to have them out by Monday.
 

Dr.Jeff

True Classic
Ha, we were both typing at the same time...I just edited my comments to make them a little more clear so please look back at it again.

But to address the testing question. That is something you can do yourself. You'll need to make a simple rig with a high pressure pump (like the stock FI one), four graduated cylinders (or similar measuring containers), a stopwatch, a fuel rail with pressure gauge, a electrical "trigger" (12V to all four injectors), and either something safe like mineral spirits or not safe like gasoline to run through them. Basically you will pump the "fuel" through all four at the same time, for a specified period of time, and measure the volume of each at a specified pressure. That will allow you to calculate the flow and consistency. To determine the spray pattern you will observe each through the graduated cylinders and compare the "cone" to some good reference examples (found online). Some of this could be done on the car to make the rig easier to build. There was a thread were a couple examples of test rigs were shown, hopefully you can find that discussion.
 

Dr.Jeff

True Classic
Also, I wouldn't bother with having the CSI cleaned, so long as it works reasonably well (i.e. it sprays any fuel). And you might find a little less expensive cleaning service. Karl posted some suggestions in the thread I noted earlier.
 

adream8

AntnyG
Ha, we were both typing at the same time...I just edited my comments to make them a little more clear so please look back at it again.

But to address the testing question. That is something you can do yourself. You'll need to make a simple rig with a high pressure pump (like the stock FI one), four graduated cylinders (or similar measuring containers), a stopwatch, a fuel rail with pressure gauge, a electrical "trigger" (12V to all four injectors), and either something safe like mineral spirits or not safe like gasoline to run through them. Basically you will pump the "fuel" through all four at the same time, for a specified period of time, and measure the volume of each at a specified pressure. That will allow you to calculate the flow and consistency. To determine the spray pattern you will observe each through the graduated cylinders and compare the "cone" to some good reference examples (found online). Some of this could be done on the car to make the rig easier to build. There was a thread were a couple examples of test rigs were shown, hopefully you can find that discussion.
Wow, I love this level of detailed information. You're appealing to my inner science nerd. 🤓 Thank you.

I'll see if I can find the thread you're referring to, or maybe a video of someone demonstrating the rig you describe. I'm able to visualize it. Doesn't sound too complicated. But would probably help for me to see it in action.
 

adream8

AntnyG
Also, I wouldn't bother with having the CSI cleaned, so long as it works reasonably well (i.e. it sprays any fuel). And you might find a little less expensive cleaning service. Karl posted some suggestions in the thread I noted earlier.
Yeah, it occurred to me that I might be able to skip the CSI, or just give it a "home carb cleaner bath". That 1-8 seconds probably doesn't necessitate top precision. And I'm in LA. Yesterday it was 99* where I was working on the car, so the CSI didn't even fire (0 seconds @ > 95*). 😂 On those chilly 65* days when it fires for 3 seconds, I'll probably survive.

RC Injector is my local. They're supposed to be really good. It's $28.50 per. I could mail them off elsewhere for a few bucks less, but then I'd have to wait for a pretty long turn around and pay for shipping. So it comes out about the same. And this way I can drop them off one day and pick them up a day or two later. I'm like a kid at Xmas. I just can't wait! 😃
 
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kmead

Old enough to know better
To get it running go ahead and do the 9v plus carb cleaner.

To get it running properly consider getting them cleaned. They usually replace the filter and get them to spray a similar amount of fuel, getting them all to work the same is the goal so the engine actually gets what the ECU thinks it should have.
 

Dr.Jeff

True Classic
Since you are in LA, check with Kerry Green at GB, they are located in Long Beach. I don't know what they charge but might be worth a look.
gbreman.com

Regarding finding low priced new injectors. The best price I've found for non-original ones that can "work" on the X was a couple years ago for about $30 each, so not much more than getting them rebuilt. However that was a reduced price and normally they sell for more. And they are not direct replacements, but have a different flow rate which is not ideal on a stock system. Otherwise I've never found any with the same spec as the stock injectors for anything near that price. Unless the existing ones are physically damaged they they can be restored to new condition. But that doesn't mean going "rebuilt" is for everyone. If you do decide to buy new, be sure of what you are getting. Some vendors are listing replacements that are not the same spec as the stock ones. They will "work", but not offer the correct flow, etc. And there are some brands of new ones that seem to be very short lived. I've always had good luck with genuine Bosch injectors.
 

Rupunzell

Bernice Loui
When injectors are sent for cleaning by a proper injector cleaning service much more happens to them than just "cleaning".

Injectors are cleaned, Inlet filters replaced, new O-rings installed, Pintel caps replaced, then they are flushed and checked for spray pattern and injector flow volume. This process will catch dead or problem injectors that typical DIY cleaning never could.

Knowing flow volume allows injector matching which helps engine performance in various ways.

New injectors can benefit from being tested to assure they function properly, New does not assure proper function and meeting specs.


Bernice
 

ted83x

Daily Driver
I have found if you send injectors out for cleaning/service, if possible send them at least 2 sets, or maybe more if they are really old. Tell them you want one good set, some just might not really work. Ideally if you can match them to a currently available new injector, that might be a better option, although new ones could cost more.
 

lookforjoe

True Classic
Newer style injectors are way more reliable than the old pintle clunkers used for L-Jet, the problem is you'd need to rework your fuel rail and intake runners to use any of them. I did do that, but doesn't really make sense unless you are also upgrading to a more refined EMS.

You can get a full set of remans from MWB for $209, so unless the $150 you were quoted includes full refurbishment of the injectors, I'd personally go that route
 

Rupunzell

Bernice Loui
Over the years of dealing with cleaning injectors it has always been at least two sets for clean/service. This way, if there is a dead or problem injector it can be properly disposed of. When the injectors are back with their flow and service data, set of matched injectors (within reason) are selected, installed with new injectors related seals and related. This can make a significant difference in performance and fuel consumption. Improved fuel efficiency with improved performance pays for the cost of fuel injectors being serviced over time.

Longer term rewards -vs- short term gratification.
Bernice
 

Michael Oxman

The Journey Begins!
I went with a professional cleaning and my injectors were so clogged (25 years off the road) he almost gave up on them. I'm glad I didn't try this myself only because it would have ended up being a lot of effort with likely no result.
 

Dr.Jeff

True Classic
My contact at one of the cleaning services (he is the company's engineer) says that short of any physical damage they can bring used injectors back to new specs. However like Michael found in his case, severely dirty ones require more time to get clean. Many services will not bother to invest the time and rather say the injector is not good. So results may very.
 

adream8

AntnyG
So today I dove in and detached the air intake and took out all the injectors.

(Note to newbies — use the rear access panel to more easily get to the 12 & 13mm main bolts. And hit the 4mm Allen bolts that fasten the injector brackets with a healthy amount of penetrating oil and use slow steady strictly perpendicular supported ratcheting pressure to keep from breaking them. Tap them squarely and lightly between tries to help unstick them.)

I was only able to hear the cold start valve and 1 injector click open when I applied electricity to them with a 9V battery. The other 3 injectors didn’t move at all, as far as I could tell. And with the CSV and the one injector that did click, I couldn’t get any carb cleaner to pass through either of them either forward or by back flushing. So they must be very gummed up. And the others are so gummed up that they won’t move, or their electric coils may actually have died. I’m hoping it’s the former not the latter. I don't really see why they would die just from sitting.

Reasonably satisfied at that point that I had done what I could on my own, I drove them all to RC Injector in Torrance. They said they should be ready by tomorrow. And they said I won’t be charged for any that can’t be resurrected.

Tune in tomorrow..
 
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adream8

AntnyG
My contact at one of the cleaning services (he is the company's engineer) says that short of any physical damage they can bring used injectors back to new specs. However like Michael found in his case, severely dirty ones require more time to get clean. Many services will not bother to invest the time and rather say the injector is not good. So results may very.
I will definitely ask them if they can be treated longer, if they call me tomorrow and tell me one or more of them is no good.

Thanks Jeff!
 

Rupunzell

Bernice Loui
The cold start injector brought in for cleaning?
BTW, cold start injectors could be a replacement issue if broken.


Bernice

I was only able to hear the cold start valve and 1 injector click open when I applied electricity to them with a 9V battery.
 
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