Fuel injector cleaning thru the rail, what detergent?
 

I'm considering trying a thru rail fuel injection cleaning to try and improve my off throttle stumble (which despite my best efforts is not completely eliminated). Amazon sells them for about $50 but they do not come with cleaning fluid, nor do they specify what to use.

This is what I'm considering. https://a.co/d/j482uly

Probably a high concentration of something like BG44k, mixed with gasoline?

Cleaning the injectors is not likely to help but sometimes the injector cleaner does a half decent job with the carbon, or at least it used to back in the day when you get good injector cleaner. You might be better off doing a walnut blast job if you suspect carbon is your issue.

Something with PEA like Techron is what I've read supposedly works to clean fuel systems.

I'm not so sure that will fix it as well.

What have you checked for that so far?

I've never seen a cleaning kit like that. I'm betting it doesn't really work. Why not just remove them and send them out for the good ultrasonic cleaning and you can see how they all flow.

Every so often I'll put a can of the berryman B12 in the tank. I guess it helps but I don't really know. 300 miles before every oil change I'll put a can down the oil cap. There's still carbon everywhere but the sludge is definitely way less than when I got it. It's more aggressive than the sea foam.

As far as cleaning the injectors that kit is by far the best way to go about it without removing the injectors. The 3.0L might have the Siemens (I think) injectors that have ceramic seats and will be ruined by ultrasonic cleaning.

The fuel line disconnects easily. Carb cleaner, taped straw, and a helper will do. It's old school. The engine will run while being sprayed with carb cleaner.

Try this stuff in the tank.

https://www.atschemicals.com/

This is what they use at the dealer. They pull the fuel pump fuse, hook this up to the fuel rail, put in a bottle of the same Techron or whatever brand fuel injector cleaner that they sell to put in your gas tank, and then hook the bottle up to compressed air and let the car run until it is empty. Bam - $150 fuel cleaning service (or $250 if german car)


Whether it works or not I am not convinced.

They run the car on straight techron? No mix of gasoline?

Definitely considered this but time is hard to come by these days with a new 9 month old in the family...also, if a tool like this works it would be useful for other vehicles.

Yes, just at idle in the shop, until it runs out and the engine just shuts off.


This was at the Nissan dealership where my brother was a master tech. I used to hang out there on the weekends.

The AC Delco cleaner might be a good choice.

Can anyone confirm if this is true? Obviously I won't consider sending them out if it is.

Ask whoever it is you want to send the injectors to. Did you not buy the cleaning tool from Amazon ?? That would be your best investment and best chance for getting some improvement by helping with the carbon.

I have the Snap-On version which was $300 or $400 in 1980s money so that is a unit is steal! Unless you want to support your economy and go with the Snap-On one ?? ;)

ACDelco GM Original Equipment 10-3015 Engine Cylinder/Combustion Chamber Cleaner - 32 oz

Any updates?

It might be interesting to hear what the company doing the cleaning has to say.

It might be interesting to hear what the company doing the cleaning has to say.

I tried calling Hurst Injection (they were recommended by some folks on the E46 forum) but went to VM. Maybe a bad idea but I went ahead and sent them my injectors. Should arrive Monday. Hopefully they didn't go out of business or something. There was a more local injector servicing company (RC Injection) but I don't know anything about them and their per-injector rate is more than double ($17 vs $35). If the new injectors don't make any difference I'll revisit doing combustion chamber cleaning.


One thing I have noticed is there appears to be a lot of oil inside the intake. Even some of the injectors had a coating of oil where they penetrated the manifold. A bit of reading on this and while I'm waiting on the injectors I'm also going to try the "O2Pilot Mod" which supposedly reduces oil consumption. Basically increases crankcase vacuum if I understand it correctly. Not sure if this is related to driveability issues but it might be contributing to deposits inside the combustion chamber.

Finally got my injectors back from Hurst. Haven't done any length of drive yet so not sure of the effect but got them installed and the "02 Pilot" mod done. Seems like it was needed though.

https://hurstinjectorservice.com/


Prices
Single injector - $17.00
Set of 4 - $68.00
Set of 6 - $102.00
Set of 8 - $136.00
Plus $10.00 shipping

Thanks for posting results. We can now test resistance to 12.3 ohms. Nice improvement for matching results. Wow! If my X5 is down for a significant amount of time for maintenance, I'll ship mine for cleaning.

Yeah it's interesting too because I had run a bunch of injector cleaner thru the system prior to this, so I suppose there's a limit to what they can do. Like three cans of BG44k.