Pressurized fuel injector cleaning (In car)

[Infinitiguy19]

The dealer wants $140 for the BG service, A local gas station wants $100. I assume the extra $40 is for the rental and the knowledge from a tech that has been at the dealer since 1993.

But what if I buy the canister (Harbor Freight used to sell it) and do it my self? Harbor Freight makes the worst everything known to man. I assume something bad happened and that's why they no longer sell the tool?

How much CFM is needed to operate the canister? I have a small 2 gallon air compressor hooked up the a spare tank. Do I need a shop air compressor (I have access too) or can I do it at home?

And how would one route the lines so the fluid does not go back into the gas tank and still keep the fluid in a loop?

[ThatsMyQ2Go]

I would suggest not hooking up an air compressor...I personally would get a drip tank (harbor freight is fine) and hook it up to a vacuum line (brake booster is most accessible), letting the vacuum of the car pull in the cleaner...its what we do in the shop for an FI cleaning

[Infinitiguy19]

And that method cleans the fuel injectors or just the intake, valves and piston tops?

[Q451990]

Sounds more like he's referring to an intake cleaning, not a rail flush. I don't know any way to clean the injectors without pushing the fluid through the rails at a pressure similar to the pressure that fuel moves through the system.

Heath

[Infinitiguy19]

I am thinking about buying a Pressurized Fuel Injector Cleaner Canister. The thing is I am not sure how it would hook up to the fuel rails. Would I tap into both input and output lines? Meaning the canister would supply the cleaner to both lines.

I would not mind lending it out to people with air compressors that can power the thing. Provided of course you pay for the tool before I send it out and maybe a $20 tip?

[Unnatural1]

If you do end up buying a pressurized canister to do this job yourself, make sure it has a pressure gauge and a regulator. In order to do this correctly, you need to first disable the fuel pump (pull a relay, fuse, etc...), disconnect the high pressure fuel line (at the fuel filter), and clamp off the return line to prevent your fuel cleaner from returning to the tank. You want the engine running exclusively from the cleaner. Connect your canister to the fuel pressure line to the engine you disconnected earlier. Set the regulator on your pressurized canister to around 35-40 psi. Start the engine and let it idle until it dies or nearly dies. That is how it's done from a guy who's done it.

Hooking this up to a vacuum line on the engine will not clean your injectors. But, it will waste all of you fuel injector cleaner!

[qship96]

In 289,000 miles of ownership, my Q has NEVER had any fuel system cleanings other than an occasional bottle of Redline Si-1 thrown in the tank,and still operating like new with original injectors. Same with previous G I owned for 150,000 miles.........


See above.......the "fuel system cleaning" so pushed by dealers and mechanics is just another of many over-sold services for the shops......BG's entire "menu" of "services" is just a program designed to line the pockets of shops and provide them a quick profit from quickly performed services, with little real benefit or need to the consumer.

[Unnatural1]

That is just super information.

[qship96]

Some of the most valuable information isnt to be gained from a multiple choice test!

[Infinitiguy19]

Thank You.

[Infinitiguy19]

I bought a fuel injection cleaner canister. Overpriced for what it is but needed none the less some say. I wish I had better news to report but I ran the BG fuel system cleaner at 60 PSI using the method Unnatural1 gave me. The engine ran horribly at around 500 RPM idle (Dash Tach). When the fluid ran out in the container I took the top off to find black fragments in the container. Before putting the cleaner in I cleaned the canister with brake parts cleaner to make sure its as clean as can be. The can of BG fuel system cleaner (Red 11 ounce can) was made in 2008 but I was told the cleaner never expires.

Point is if I spent ~$100 at the dealer or any shop that offers this service the very slight idle vibration I have ALL THE TIME would have never been resolved. Some of my exhaust isolators are missing and the heat shields on the exhaust are loose. But the intake is as clean as can be. The plenum is decent, not clean enough to eat off but not caked with carbon. The throttle body is clean, The IACV/AAC is clean (Cleaned with dental picks for hours a year or two ago). Fuel pressure is at 32 PSI at idle (Harbor freight gauge) Fuel filter replaced every year. Valve covers resealed two weeks ago (Non more oil on spark plugs)

Some times when the car has been sitting overnight and I start it up the car shakes like a bad injector. But all test fine (hot and cold). But 1000000% of the time there is always a vibration no matter how slight its there. When the car is warm and I try to start it (hot soak) it will run then stall. The second time it will idle decently.

I am beginning to think this (idle vibration) is not worth fixing. As I have been chasing it for as long as I have owned the car. I can't find a shop I can trust (local dealer included) so I am struggling a little.

So at this point I think without the exhaust isolators/heat shields in the picture it comes down to either electrical or compression.

[Q451990]

I can't imagine how there would be anything in the canister when you were done, unless your air supply was dirty?

Heath

[Infinitiguy19]

The canister has a check valve. So if one wanted to tee in the canister to the fuel rail nothing would come up to the canister. I think its more likely that the cleaner fluid ate away at the plastic thing at the bottom of the can maybe.

[qship96]

In 289,000 miles of ownership, my Q has NEVER had any fuel system cleanings other than an occasional bottle of Redline Si-1 thrown in the tank,and still operating like new with original injectors. Same with previous G I owned for 150,000 miles.........


the "fuel system cleaning" so pushed by dealers and mechanics is just another of many over-sold services for the shops......BG's entire "menu" of "services" is just a program designed to line the pockets of shops and provide them a quick profit from quickly performed services, with little real benefit or need to the consumer.

See above!

[Infinitiguy19]

Power Balance numbers after said cleaning:



------------------------------------------------------------------------------
Power Balance Test Summary On 8/15/2012 12:15:27 PM
Coolant Temperature: 180 Deg {F}
Idle Air: 77 %
Cylinder # 1
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 661 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 600 Rpm
Average RPM Drop Result... 61 Rpm
Highest RPM Drop... 123 Rpm
Amount Of Data Sampled When Cylinder Off... 572
Cylinder # 2
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 655 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 608 Rpm
Average RPM Drop Result... 47 Rpm
Highest RPM Drop... 105 Rpm
Amount Of Data Sampled When Cylinder Off... 570
Cylinder # 3
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 650 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 614 Rpm
Average RPM Drop Result... 36 Rpm
Highest RPM Drop... 75 Rpm
Amount Of Data Sampled When Cylinder Off... 572
Cylinder # 4
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 652 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 617 Rpm
Average RPM Drop Result... 35 Rpm
Highest RPM Drop... 77 Rpm
Amount Of Data Sampled When Cylinder Off... 571
Cylinder # 5
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 658 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 621 Rpm
Average RPM Drop Result... 37 Rpm
Highest RPM Drop... 83 Rpm
Amount Of Data Sampled When Cylinder Off... 570
Cylinder # 6
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 656 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 633 Rpm
Average RPM Drop Result... 23 Rpm
Highest RPM Drop... 68 Rpm
Amount Of Data Sampled When Cylinder Off... 571
Cylinder # 7
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 658 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 621 Rpm
Average RPM Drop Result... 37 Rpm
Highest RPM Drop... 83 Rpm
Amount Of Data Sampled When Cylinder Off... 575
Cylinder # 8
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 668 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 634 Rpm
Average RPM Drop Result... 34 Rpm
Highest RPM Drop... 68 Rpm
Amount Of Data Sampled When Cylinder Off... 569
------------------------------------------------------------------------------

------------------------------------------------------------------------------
Power Balance Test Summary On 8/15/2012 12:19:34 PM
Coolant Temperature: 180 Deg {F}
Idle Air: 100 %
Cylinder # 1
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 740 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 685 Rpm
Average RPM Drop Result... 55 Rpm
Highest RPM Drop... 102 Rpm
Amount Of Data Sampled When Cylinder Off... 568
Cylinder # 2
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 738 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 690 Rpm
Average RPM Drop Result... 48 Rpm
Highest RPM Drop... 100 Rpm
Amount Of Data Sampled When Cylinder Off... 570
Cylinder # 3
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 737 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 628 Rpm
Average RPM Drop Result... 109 Rpm
Highest RPM Drop... 212 Rpm
Amount Of Data Sampled When Cylinder Off... 572
Cylinder # 4
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 737 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 691 Rpm
Average RPM Drop Result... 46 Rpm
Highest RPM Drop... 87 Rpm
Amount Of Data Sampled When Cylinder Off... 572
Cylinder # 5
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 737 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 630 Rpm
Average RPM Drop Result... 107 Rpm
Highest RPM Drop... 187 Rpm
Amount Of Data Sampled When Cylinder Off... 572
Cylinder # 6
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 732 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 634 Rpm
Average RPM Drop Result... 98 Rpm
Highest RPM Drop... 157 Rpm
Amount Of Data Sampled When Cylinder Off... 571
Cylinder # 7
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 736 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 557 Rpm
Average RPM Drop Result... 179 Rpm
Highest RPM Drop... 311 Rpm
Amount Of Data Sampled When Cylinder Off... 573
Cylinder # 8
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 736 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 692 Rpm
Average RPM Drop Result... 44 Rpm
Highest RPM Drop... 86 Rpm
Amount Of Data Sampled When Cylinder Off... 573
-----------------------------------------------------------------------------------------------------------

[Q451990]

In 289,000 miles of ownership, my Q has NEVER had any fuel system cleanings other than an occasional bottle of Redline Si-1 thrown in the tank,and still operating like new with original injectors. Same with previous G I owned for 150,000 miles.........


the "fuel system cleaning" so pushed by dealers and mechanics is just another of many over-sold services for the shops......BG's entire "menu" of "services" is just a program designed to line the pockets of shops and provide them a quick profit from quickly performed services, with little real benefit or need to the consumer.

See above!

I have seen power balance numbers at T3 with multiple trials using a real consult both before and after the BG flush that show more consistencey between cylinders after flush. Maybe the difference is due to the updated injector design vs. the older ones. Either way, your not needing service does not automatically mean it's a rip off.

Heath

[Q451990]

Infinitiguy19,

I have never gotten consistent enough results from that software to make me think that there's any useful information from the test except for possibly identifying a dead miss.

Heath

[ericthered]

With my '91 and '92 Q's lots more injector problems than with my '94. The newer design is better... and California gas just makes it worse. A diet of BG44K rarely + always using gas with techron helps.

That said, my injectors have all failed electrically. I published a while ago. The key was measuring ohms when injectors are hottest. This occurs 10 minutes AFTER you shut down the hot engine. Like jet engines, the coolant is the flowing fuel.

Any time I saw differences between hot and cold, it would be a matter of time before I had to replace that fuel injector next.

That said, I am still confused how poor California gas effects the injectors electrically. As far as doing all this injector cleaning, if the problem is almost always electrical, I would doubt this fixes much that the occasion BG44K in the tank + techron doesn't take care of.

[Infinitiguy19]

I forgot to add that I have been using Costco fuel for a few months because of the price and location. But recently I switched to Shell. I used Redline S1 in a half a tank of fuel which made little if any difference. The car rarely sees anything above 2K RPM's and I drive at 55 MPH no more than that because that would bring the RPM's a little higher than 2K RPM's.

I have not tested the fuel injectors after a ten minute hot soak but I will do that ASAP. But the bad injector like shake happened again this morning after a rain storm. Come to think of it, it mostly happens when the car sits over night and moisture builds up on it.

I have grounded the fuel pump and taken the car for a drive and I noticed no difference whats so ever. So the fuel pressure may not be a issue at all.

I plan on doing a fuel pressure leak down test and seeing if possibly a o-ring let go or something. But that is just another test that will come back normal I bet. At this point I know its a fuel injector I am just saddened that it can be because they were all replaced a few years ago. I guess I will be doing the plenum next summer.

If I could find someone I could trust locally I would hand them the keys and tell them to fix it and not come back till they can balance a quarter one the plenum!

[qship96]

I am not a big fan of any solvent based fuel system cleaners, as my gut says the solvent is very hard on plastics{injector bodies},especially older injectors that have been subject to the intense heat under the plenum of the Q engine....I feel it just accelerates the electrical winding problem that seems to be the Q injectors main source of failure mode in these old cars. Ethanol is commonly {mistakenly ?} blamed, but certainly has not been an issue in my experience using it exclusively for the last 8 or so years and 150,000+ miles

[OwnerCS]

I am not a big fan of any solvent based fuel system cleaners, as my gut says the solvent is very hard on plastics{injector bodies},especially older injectors that have been subject to the intense heat under the plenum of the Q engine....I feel it just accelerates the electrical winding problem that seems to be the Q injectors main source of failure mode in these old cars. Ethanol is commonly {mistakenly ?} blamed, but certainly has not been an issue in my experience using it exclusively for the last 8 or so years and 150,000+ miles

I tend to agree.. Soon after I got my Q I wanted to run (fill in the blank) fuel system cleaner through it to make sure the injectors were all clean for optimal performance. I don't believe I had used the tank of fuel with the cleaner additives before two injectors failed on the same weekend. Sometimes too much of a good thing isn't always wonderful.