Hey folks,

I have been reading a lot about fuel additives and been trouble shooting my surging idle. I tried cleaning the maf, resetting the battery changing plugs and everything but nothing worked. So as of now the last hurrah is to use either seafoam (not really leaning towards it) or the BG 44k (poured into tank).

My question is will the BG 44K benefit me being my engine is a direct injection? will it clean the valves and injectors?

anyone could chime in please?

Best
Sam

 

BG makes quite a few cleaning kits, including one for DI engines. It doesn't go in the tank though. I've used a product from CRC, although who knows how much it really helps. I did it when it was time for an oil change and will probably continue to do so since it's only around $10-15 for a can once a year.

 

BG44K is the only fuel additive used and recommended by JLR on the AJ126 and AJ133 DI engines. Many dealers chuck a can of it in when doing a service or oil change.
However the jury is out on what effect if any it may have on carbon build up on the inlet valves. Probably no effect at all, but it works quite well to clean fuel lines, injectors etc, so if I were you I would chuck a can in anyway, it can't do any harm and you have nothing to lose but the cost of a can!

 

No fuel tank additive will do anything for intake valve cleaning as the injectors re downstream.

The Jag DI engines do not have a known problem with clogged injectors or intake valves.

Look elsewhere.


BTW- please don't use Seafoam anywhere near a modern engines. It was designed for WWII vintage 2 stroke outboard motors with gummed up carburetors. The major ingredient is 50% light oil, the last thing you need more of in an engine.

 

Pretty much have to take off your intake manifold and directly clean the intake valves. BMW dealerships do this as a $800 service for their cars.

It stinks, but there's a price to pay for all the HP, emission, and fuel economy benefits of direct injection, and this is the price.

 

I'm not so sure about...."jag DI don't have known problem with clogged injectors or intake"

There have been numerous post of injector replacements. As for the carbon on the valves, there is a thread on engine rebuild and his are caked.

I honestly think all of these rough idles have to do with carbon build up. My car ran smooth until 35k miles. Now I have a lumpy idle. No codes after replacing supercharger vacuum hose. Still lumpy and a little better after it warms up.

I do notice that I get "pending" misfires and first 1000 revolutions codes occasionally, but it never throws a CEL.

 

Is this what you are getting when you said lumpy idle? This is my car and this idle been driving me crazy lol. As soon as I put it in Drive and go it is fine it only happens when it sits for a minute or longer starts happening again.

 

What exactly do I need to remove to spray crc intake cleaner into? And I need to spray cleaner past the MAF sensor right? I have a 09 xf sc fyi. Thanks for instructions.

 

There is no recommendation from Jaguar to use this or any other additive. Land Rover states only to use it on certain models only as an initial troubleshooting step and very very sparingly.

 

Actually I think they all use it. I just recently serviced my XF at Jag dealership (oil change) and they put a can of BG 44k. I was reviewing my bill and saw that they poured one into the tank. They charged $25 for the can.

 

Yes but that's a dealer invented task- not Jaguar factory endorsed at all. I'll go as far as saying an upsell of little value.

 

Here is the carbon build up on my N/A 5.0 Jag at 88,000 miles

 

How was this condition remedied?

 

Holy **** (America) or the equivalent in UK (Bloody hell)... How did you fix that?

I know definetly going to assume (from now on) there is no DI engine that is not suffering carbon buildup. Thought that this was more common on the german autos but appearantely it is on all vehicles with DI.

 

+1

Its called walnut shell blasting...here's a video


I think some good intake cleaner and a wire brush accomplishes about hte same thing. no?

 

It wasn't. This is actually not that bad compared to the German cars, especially Audi! I will put another 40,000 and then have it walnut blasted.

 

Do you think the BG GDI cleaner would be any good? it is sprayed directly in the throttle and supposedly removes the carbon deposits on the intake valves

 

Thank you. The volume of contaminants is not that dissimilar to what was commonly seen in the valves of V8s back in the '60s when leaded fuels were used. Those engines didn't care either.

 

If you want to spray CRC GDI Spray cleaner you will need to find a vacuum line. Let car get to operating temperature. Unplug the vaccum line, stuff a paper shop towel about an inch into the end to create suction when engine is on. Wedge the spray nozzle into the vaccum line. Turn your engine on and run it to 2K RPM (two person job...or figure a way to keep engine idling at 2K). Spray short two second burst of the CRC cleaner, waiting about five to ten seconds in between bursts until can is empty. Reattach vaccum line. Rev car to 4-5K RPM a few times. Let it idle on its own for about five minutes, then take it out for a hard run on the freeway to clean up all the junk that was loosened up.

Since I already have my intake and supercharger off, I am using a brush and CRC to clean the intakes directly.

 

I have heard shops use it as a upsell. Anything that gets behind the valves will help a little bit. The thing is once the deposits accumulate, they are hardened on by heat and that is why walnut blasting is what it takes to clean them to new spec. So, if you do the BG or CRC cleaners through intake of vacuum line they will get rid of newly accumulated film, but not the hard stuff.