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Fuel Injector Cleaning

Old Dec 18, 2010 | 10:54 AM
  #1  
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Default Fuel Injector Cleaning

What do all of you do re fuel injection maintenance? I use Techron about every 10 tankfuls. I have not done any other maintenance on the intake side. So far, very smooth operation, no loss of fuel economy, no stumbling at low idle. A '95 with about 80k miles on it.
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Old Dec 18, 2010 | 11:01 AM
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At 78k miles, I intend to send mine out to RC engineering for some ultrasonic cleaning.
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Old Dec 18, 2010 | 12:46 PM
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At 98k I sent mine off to Cruzin Performance in Big Rapids, MI, great service, fast turnaround, etc... I use one can of Sea Foam as directed, once or twice a year. My injectors were very clean when they were tested.
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Old Dec 18, 2010 | 07:40 PM
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Mine were very dirty at 44k miles with one sticky one. I had them sent off. Well worth it and not expensive!
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Old Dec 18, 2010 | 08:31 PM
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find someone with an ASNU Test Lab, it is one of the best Injector cleaning and balancing systems out there.
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Old Dec 18, 2010 | 08:50 PM
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http://www.witchhunter.com/

This place is awesome! You get a print out of the injectors performance before and after cleaning. He also changes all the screens at the top of the injectors. You get them back in numbered bags so you can install them to have a balance from side to side.

I cannot recommend them enough!
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Old Dec 20, 2010 | 10:25 AM
  #7  
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Cup of Marvel Mystery Oil in every tankful and a can of Seafoam or Berryman's B12 every 3 tankfulls or 1,000 miles.

Nary a hiccup nor a stutter...

Gerry
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Old Dec 20, 2010 | 11:04 AM
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I do Techron RIGHT BEFORE OIL CHANGE. You do not want any solvents hanging around the case/sump. Heed this advice....

I also cannot say enough good things about witchhunter.com-awesome and fast!
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Old Dec 20, 2010 | 11:39 AM
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I've used Chevron Techron Fuel System Cleaner in my daily driver.

The problem is, without actually removing and testing the injectors for flow, spray pattern and possible leakage, there is no way of knowing if they are operating at their peak.
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Old Dec 20, 2010 | 11:56 AM
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Injector cleaning is on my to-do-list this winter.
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Old Dec 20, 2010 | 01:21 PM
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Is removing the fuel injectors a DIY? If it is are there any links on how to do it?
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Old Dec 20, 2010 | 02:53 PM
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basically remove the airbox and heater blower assembly.

loosen the fuel rail, and wiggle the injectors out.

It can be a messy with the residual fuel (unless you pull the fuel pump fuse and let the car run out of fuel by itself), but its not hard.
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Old Dec 20, 2010 | 03:14 PM
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Just Came across this for what its worth: Its about fuel additives. Source: another auto forum:

These tests were done by me to help determine the best products:

Background about tests:

As a worst case sample of material which might be found in gasoline I used ordinary tar. The brown deposits we find coating carburators, and which collects in fuel injectors and on intake valves, are the highest boiling components in gasoline. They are tar-like materials which distilled along with the lighter gasoline. The best solvent I've ever seen for these was methylene chloride, but it's expensive and I'm sure it's being phased out to protect our ozone layer. In any case, if you used it on a modern car the chlorine freed during combustion would corrode the oxygen sensor. Amoco advertises a cleaner gasoline and I'm sure it's because they've reduced these tar-like compounds. All gas these days contains at least a little detergent of some sort to help keep these deposits from building up too much.

Dimethylformamide is listed in the literature as being a good engine cleaner and is "especially good at dissolving carbonaceous deposits". I haven't used this myself because it is a bit too toxic. Instead I used N-methyl pyrrolidone, which is also good.

For my tests, I tried to use a wide variety of products, well known and unknown, expensive and cheap, and also some pure solvents in order to represent a good cross section of products on the market. Note, carbon itself (such as soot and other thermally decomposed material) is not soluble in ANY solvent but solvents like dimethylformamide and N-methyl pyrrolidone do a good job of breaking up clumps and dispersing the fine particles to release the heavy tarry materials trapped within them. However, some of these solvents are too harsh to use freely in the fuel system. (Someone in one of these forums told me that when the auto industry looks for good cleaners, they mostly look for solvents that will not attack the plastic and rubber parts in the system.)

Most cleaners (the safer & slightly less effective ones) usually have common solvents in them like toluene, alcohol, acetone or methyl ethyl ketone, and naphtha. If you want to use these to clean your system, you can get more for your money by buying the pure solvents at a hardware store and mixing them yourself. I have never had a problem adding toluene, acetone, alcohol, or naphtha to my gas tank in quantities up to one quart per 16 gallons.

Most of the straight solvents I used are at least as flammable as gasoline so be careful if you use them. The alcohol used was pure, 100% isopropyl alcohol. This has no water in it, it is not the same as "rubbing alcohol".

These test results are as fairly and accurately done as I could manage with the equipment I had available, and the other data presented is also accurate to my knowledge. Your car may have different plastics in it than mine does so if you choose to make your own cleaner, do it at your own risk.

TEST RESULTS

RELATIVE EFFICIENCIES AT WHICH VARIOUS CLEANERS WILL DISSOLVE HIGH BOILING RESIDUES FROM GASOLINE AND CARBONACEOUS DEPOSITS FOUND IN USED MOTOR OIL, (10=BEST):

· 10 Gunk Gas Treatment
· 10 Toluene (a common ingredient)
· 9 Castrol Syntec Power System
· 8 Duralube Fuel System Cleaner
· 7 Gunk Fuel Injector Cleaner
· 6 Redline SI-1
· 5 Gunk Air Intake Cleaner
· 4 Naphtha (a common ingredient)
· 4 STP Fuel System Cleaner
· 4 Seafoam Motor Tuneup
· 4 Trak Fuel Injector Cleaner
· 4 STP Intake Valve Cleaner
· 4 CD-2 Emission Cure
· 4 Prolong Fuel System Treatment
· 3 CD-2 Fuel Injector Cleaner
· 3 Techron Concentrate
· 0.5 Butyl Cellosolve (a COMMONLY used "AUTO INDUSTRY DETERGENT" for oil and grease)

THE FOLLOWING CLEANERS DO NOT HURT NYLON (LISTED RANDOMLY).
(The letters in parentheses indicate how well they dissolved the material from used oil, A=best.):

· Toluene (A)
· 2-Phenoxyethanol (A)
· Duralube Fuel System Treatment (B)
· B-12 Chemtool (B)
· Trak Fuel Injector Cleaner (C)
· Techron Concentrate (D)
· STP Intake Valve Cleaner (E)
· Seafoam Motor Tuneup
· CD-2 Emission Cure
· Prolong Fuel System Treatment
· Aromatic distillates
· Naphtha
· Butyl cellosolve
· Acetone

THE FOLLOWING CLEANERS WILL DECOMPOSE THE NYLON SOCK IN THE FUEL TANK. Listed in order of increasing severity:

· STP Fuel System Treatment
· CD-2 Fuel Injector Cleaner
· Gunk Fuel Injector Cleaner
· Castrol Syntec Power System
· Redline SI-1
· Gunk Gas Treatment
· Monoethanolamine
(The monoethanolamine is the worst here. It turns nylon black on contact. It is significant to note here that the "best" "detergents" in use today are similar, strongly alkaline organic solvents). Another use for the current bunch of organic amine "detergents" is cleaning deposits out of cylinders, so I hear.

I hope this takes the guesswork out of choosing good products.
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Old Dec 20, 2010 | 04:29 PM
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These guys did a great job for me, and had them done in 3 days:

http://www.fuelinjectorconnection.co...iewCat&catId=3

The cost (only $15 per) was cheaper than just about anyone else, too. ASNU machinery, before/after flow charts, new caps, screens, O-rings and everything. My total cost back to me with Priority shipping was right around $71. I had one injector which was off by 12%, one off by 6%, and the others were close. That was on a 163,000 mile 944S. I'll be sending my 951 injectors to them before spring.
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