2003 Nissan Micra - Spray to clean engine valves

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Thu 16 Feb 2023 12:48
2003 Nissan Micra - Spray to clean engine valves - MrD2018

I have seen a video on Youtube from America about cleaning carbon deposits from the engine valves by spraying a cleaning solution into the air intake. The cleaning product is called “Lucas Deep Clean GDI”. As it is only available in America, I was wondering if anyone knows an equivalent spray I could buy in the UK?

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Thu 16 Feb 2023 12:56
2003 Nissan Micra - Spray to clean engine valves - elekie&a/c doctor
A micra of this age is not a Gdi engine . So realistically, you would be wasting your time and money.
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Fri 17 Feb 2023 10:47
2003 Nissan Micra - Spray to clean engine valves - craig-pd130

Thee are several fuel additives which promise to remove deposits from injectors, inlet valves etc.

I've used Redline Injector Cleaner a couple of times on older cars and it seems to work: I compared the MOT emissions data on our Corsa before and after use, and the reduction in CO and hydrocarbons was dramatic. A bottle's about £18 on eBay.

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Fri 17 Feb 2023 12:10
2003 Nissan Micra - Spray to clean engine valves - Gibbo_Wirral

I'm always wary of air intake cleaning sprays. The EGR valve ones for example are a load of rubbish.

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Sun 19 Feb 2023 14:22
2003 Nissan Micra - Spray to clean engine valves - edlithgow

Thee are several fuel additives which promise to remove deposits from injectors, inlet valves etc.

I've used Redline Injector Cleaner a couple of times on older cars and it seems to work: I compared the MOT emissions data on our Corsa before and after use, and the reduction in CO and hydrocarbons was dramatic. A bottle's about £18 on eBay.

Didn't that require you to pay 2 test fees, or are you on very good terms with the test centre?

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Sun 19 Feb 2023 16:26
2003 Nissan Micra - Spray to clean engine valves - craig-pd130

Didn't that require you to pay 2 test fees, or are you on very good terms with the test centre?

It was from one year to the next. The HC and CO readings were quite high at the previous MOT (even though it is regularly driven quite hard) so a couple of weeks before the latest one, I fed the car two tankfuls with the Redline stuff in.

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Fri 17 Feb 2023 12:51
2003 Nissan Micra - Spray to clean engine valves - edlithgow

Inlet valves have to be pretty badly clogged to become an issue. This happens with GDI engines because they don't get washed with petrol entrained with the incoming air.

Have you confirmed you in fact have clogged intake valves?

You could do this with an endoscope (fairly cheap now). If you do it by taking your inlet manifold off you may as well clean them with a toothbrush and petrol, or perhaps brake fluid, which is a very good solvent.

I suppose brake fluid might work as a spray but I've never tried it.

I cleaned the EGR plumbing on a Honda Accord with brake fluid, but that was completely plugged with soot, so required supplementary coal mining techniques to get the brake fluid to where it could do some dissolving.

If, OTOH, your cylinders are coked up, a distilled water spray is effective, but takes quite a long time

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Sat 18 Feb 2023 17:07
2003 Nissan Micra - Spray to clean engine valves - Lrac

If you were to dislodge a build up of carbon with a spray I wouldn't think your cat would appreciate it. As previously stated I wouldn't have thought this car is direct injection

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Sat 18 Feb 2023 23:21
2003 Nissan Micra - Spray to clean engine valves - edlithgow

DP. See below

Edited by edlithgow on 18/02/2023 at 23:49

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Sat 18 Feb 2023 23:47
2003 Nissan Micra - Spray to clean engine valves - edlithgow

If you were to dislodge a build up of carbon with a spray I wouldn't think your cat would appreciate it. As previously stated I wouldn't have thought this car is direct injection

One never knows, but a spray isnt likely to be effective enough to remove it in chunks (except just possibly if you use enough volume to achieve significant thermal shock, which should be avoided anyway).

If its very bad and you leave it it may come off in chunks anyway, but probably only a significant threat if you have a turbo.

Cleaning the Honda Accord EGR plumbing with brake fluid (not as a spray, but as liquid which pooled in the pluming until it drained away as I broke through the clog with a wire), it occurred to me at the last second before starting up that it might have hydro locked a cylinder.

Turned it over with the plugs out and quite a lot of black stuff erupted. Phew!

Smoked A LOT on startup and for about 20 mins after. No obvious adverse effect but maybe didnt promote catalyst converter longevity

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