Water decarbonisation

[Falcon_LS]

Well, I'm going to give this a try and see what sort of a difference there will be afterwards. My Grand Marquis knocks slightly with 91 AKI under heavy load and it's even worse with 87. 80% of my driving is highway (using cruise control), but I reckon the previous owner's trips consisted mostly of short stop-and-go trips.

I'm considering filling up a sprayer bottle with hot water, and inducing it slowly through the brake booster vacuum line whilst operating the throttle by hand (2-3k rpm) with the engine at operating temperature. But I was wondering if it would be more effective if I was to spray it straight into the throttle body?

On another note, I will be using Liqui-Moly Pro-Line Engine Flush when I change my oil next week. Should I just skip this and just flush the engine instead? Wondering if cleaner ring packs would help partially solve the problem. Thanks!

 

[MarkM66]

Originally Posted By: Falcon_LS
On another note, I will be using Liqui-Moly Pro-Line Engine Flush when I change my oil next week. Should I just skip this and just flush the engine instead? Wondering if cleaner ring packs would help partially solve the problem. Thanks!

What do you mean by "flush the engine instead?"

I wouldn't put any flushing liquid in an engine, but that's just my stance.

As for adding water to the intake, I guess anyway you get it in there in a controlled way would work.

 

[eljefino]

Spraying into the TB might distribute it better than through the booster vacuum hose.

If you can get some real small diameter hose, maybe 4 mm inside diameter, its outside diameter might fit in your brake booster hose. Then you can just rev the motor and stick the hose in a jug of water. Way less work.

You of course don't want to hydrolock, but you won't with a small diameter hose.

 

[meep]

some booster hoses pull off one far end of the manifold. in that case, going in thru the throttle might be better.

if that doesn't help, do same with seafoam, except let it eventually chug to a stall. then let it sit for 30. then restart it and drive it immediately.

I'd do this somewhere away from people, NOT in your neighborhood. it's smokey as [censored] and really not a kind thing to do to folks around you.

m

 

[rslifkin]

With a V8 revved to 2500 or so, you'd be surprised just how much water it will take and not even notice. A spray bottle is probably not enough to do anything.

When I did this on my Jeep, I held it around 2500 - 3000, and took a garden hose set to mist, and gave it intermittent bursts (quite a bit of water). Make sure to keep the idle up for 10 - 15 seconds after you finish spraying, otherwise it won't be happy (intake still too wet). After that, I took it for a HARD drive, and it seemed to help.

 

[sunfire]

You have to get the engine hot otherwise the water won't decarb anything. The finer the mist the better. Which is why I'm going to use a hand held steam cleaner connected to the PCV next time I do a water decarb.

But if you don't have one available you can try to hookup a basketball needle to the PCV hose.

Never tried using a spay bottle but it should work just fine if you spray into the TB.

But IMO using a hand steamer is going to produce a hotter finer mist that will distribute better to all the cylinders.

 

[paulo57509]

The thought of using a garden pump sprayer to introduce water through the throttle body often comes to mind......

 

[Kuato]

I had a similar issue years ago; the vehicle's engine had been designed to run on 87 octane. The previous owner always put 93 in it.

When I got it, it knocked under load on 87. I used STP gas treatment (or similar) for a few tanks, and stuck with the 87 octane. After about 3 tanks of gas the knocking was reduced, and it was gone after a couple tanks more.

IMO no extreme action is needed, just keep your foot out of the "knock zone" while the correct fuel and fuel tratments do what they're designed to do.

But if you decide on the water injection method keep in mind that each engine is different so the volume you will need might be way different than what others used. Also, you will probably want to change your oil immediately after since water may have found its way into the crankcase.

 

[Spazdog]

Originally Posted By: paulo57509
The thought of using a garden pump sprayer to introduce water through the throttle body often comes to mind......

I've often considered fitting a patio mister just for that purpose. You can get a 1gph mister nozzle pretty cheap and probably fit it with a wrecking yard windshield washer pump.

 

[flanso]

Take the hose off of a windshield washer nozzle and temporarily plumb it somewhere into the intake stream. You will need a restrictor for the water flow; the intake air velocity will pretty well atomize the injected water. On the highway, actuate the washer stalk a few times. Years ago, I installed a similar, but more elaborate, set up on an Audi 5000 Turbo. My purpose was to facilitate higher boost, decarbonization was an added benefit.

 

[punisher]

Something to bear in mind is that MAF sensors cause a lot of pinging when they get dirty due to lean issues. It is also possible that FoMoCo offered a PCM reprogram for a pinging problem as well on that model/calibration.

 

[Shannow]

Back in the day, I used to solder a little piece of brass into the bottom of a peach tin, and add some aquarium pump hose and "needle" valve to control flow.

Put it on a vacuum port, rev it to a few grand, and 700ml could be fed through it quite quickly without stumbling.

 

[dwcopple]

[censored] is a peach tin?

 

[Audi Junkie]

a can.