Dipetane etc for reducing emissions?

mankteln

Have NCT later this week and last year my CO emissions on high idle were close to the threshold (0.18, limit is 0.2) and after a years driving I'd guess it could be over. Was thinking of trying Dipetane (or something similar if anyone's any suggestions), Anybody had much success with it?

biko

There are many threads on Dipetane and I even use it myself sometimes, but afaik there is nothing conclusive saying it works.

Just go buy a fuel system cleaner for your car (petrol/diesel) and use all of it, then drive the car hard for a few days to blow any cobwebs out.

mikeecho

I agree with biko.

Personally, I'd run some BG 44k or 244 and drive the living siht out of the car.

I generally give the car a good thrashing (at least) once a week, run miles plus diesel and give her the odd can of BG244., And every year my smoke is 0.01 at the NCT.

I think a lot of it is down to giving the car a good hard run regularly.

One of these days I'll be on Garda Twitter for being in the 200km/h+ club, if the Hyundai can catch up

mankteln

Cheers. I drive a petrol so doesn't have the DPF issue that I hear so much about with diesel. I'd say my catalytic converter is just feeling the years at this stage which inevitable

ht9zni1gs28crp

Try the BG44k for petrol. That stuff is the best out there. The BG244 for diesels works wonders. For €25 a tin its worth it every six months regardless.

Then you need to arrive at the NCT with the car red hot. The CAT works best when hot. 20mins of high revs driving, ie Italian Tune Up.

BronsonTB

No magic cure & every car will be different.
For the price of it, try some Dipetane & see how you get on.
I've used it in the past & the car at the time passed the NCT tests.

HBC08

Drive to the NCT centre in 3rd gear....rev the absolute sh1te of of it.This worked for me on a retest (also used diptane) one year.Failed the following year and needed a cat.

mankteln

What about dropping in one key then going back out and starting it with an another to keep the engine hot, worthwhile?
I know my da always sits in the car with the engine on when waiting for the MOT. Don't know if it's led to him passing anymore than usual though lol

ianobrien

I remember the Primera we had years ago had a section about how to drive it before a test to reduce emissions (so long at this RPM, so long idling, so long at this RPM etc)

My usual approach is a bit of an Italian tune-up. The oil temperature was 108°C at the last test. The brakes were warm also.....

mankteln

So unfortunately this didn't do the trick, only had the dipetane in from the day before but drove car hard for few hundred Kms and then in 3rd gear for half an hour before test. Low idle reading was 0.24 (limit 0.20, my reading had been 0.18 last year so knew it was getting borderline), low idle reading up a little from last year too but still under. One thing I couldn't understand was my engine oil temp was 96C this year compared to 101C last time (when I didn't do any hard driving prior)?
Anyways that probably spells the end for the car as there was a couple of other things that need doing too and there's no guarantee I'd ever get the emissions back under. One thing I'm wondering is I put it in as an early test(to see about the emissions and give myself time to do any work), am I only able to drive it until my retest date or does my original NCT still apply? To be honest I'd be looking to change as soon as possible as don't like the idea of driving a car that needs work done (wasn't fail dangerous or anything) but realistically won't get to see any cars over Christmas/new years so a bit of extra breathing space would be good.

bazz26

There could be any number of issues that could cause the higher emission readings that Dipetane simply won't fix. One of your oxygen sensors could be dirty or need replacing, or it could be the catalytic converter that is on the way out. Stick it through the NCT first and then bring it to a mechanic to have it looked over if it fails with the fail sheet.

The Rape of Lucretia

mankteln wrote: »

One thing I'm wondering is I put it in as an early test(to see about the emissions and give myself time to do any work), am I only able to drive it until my retest date or does my original NCT still apply?

You can drive it until the end of the existing NCT disc as long as they havent classed it a failed-dangerous. Retest date only refers to whether you have to do the full test or only the failure items, as I understand it.

mankteln

bazz26 wrote: »

There could be any number of issues that could cause the higher emission readings that Dipetane simply won't fix. One of your oxygen sensors could be dirty or need replacing, or it could be the catalytic converter that is on the way out. Stick it through the NCT first and then bring it to a mechanic to have it looked over if it fails with the fail sheet.

Yeah I have done so which is the issue. Have a suspension arm that needs replaced and then as you say there's so many things that could be causing the high reading it's probably not wise economically to try and sort as the risk of failure is pretty high. Timing belt/water pump interval due again too (last changed at 115k km 6 years ago, at 235k km now) so everything is going to add up. Realistically I'd do all the other work but the high emissions is the death knell, I'm not going to replace the cat on a car that I bought for €1000 18 months ago and has brought me 50k km of trouble free comfortable driving. Owes me nothing but because of that I'll be sorry to see it go

johnayo

Time to cut your losses now. Its a potential money pit now.

Toyotafanboi

Let's just take a step back from all of this OP.

There are so many contributors to an NCT or any real world emissions test that being close to a fail one year doesn't mean you are going to be close to a fail and certainly doesn't mean you'll be a definite fail the following year. The cars state of service health, engine oil, spark plugs and air filter all play a factor, the engine temp plays a very minor factor, the tester and how he carrys out the test plays a factor, the environment plays a factor, ambient air temp, humidity and so forth, even the quality and source of the fuel in the tank at the time.

I think it's also worth considering that during an initial dose of dipetane things like co emissions will actually increase as carbon deposits are being burned off from internal components, so dosing up with dipetane the day before and emissions test, if it's a first dose is quite a bad idea. If you think you have issues that dipetane can fix, you'd want to run it through a full tank of fuel then add it to a second tank before the NCT to get it down and keep it low.

What you've actually done IMO and I mean no offence (and I could also be wrong), is interfered with something that may not have posed any issue at all and made it worse. I'd be very inclined to let the voulentary early test run out now and do another full test with a new inspector in 6 or 8 weeks time and see how the car does. There's probably a fair chance it'll pass as it was only a borderline fail when necked with dipetane and even if it does fail, get a proper diagnosis of the fail, a petrol car failing emissions can often be a simple fix. It'd be a shame to write it off for a set of new spark plugs and an oil service.

mankteln

Toyotafanboi wrote: »

Let's just take a step back from all of this OP.

There are so many contributors to an NCT or any real world emissions test that being close to a fail one year doesn't mean you are going to be close to a fail and certainly doesn't mean you'll be a definite fail the following year. The cars state of service health, engine oil, spark plugs and air filter all play a factor, the engine temp plays a very minor factor, the tester and how he carrys out the test plays a factor, the environment plays a factor, ambient air temp, humidity and so forth, even the quality and source of the fuel in the tank at the time.

I think it's also worth considering that during an initial dose of dipetane things like co emissions will actually increase as carbon deposits are being burned off from internal components, so dosing up with dipetane the day before and emissions test, if it's a first dose is quite a bad idea. If you think you have issues that dipetane can fix, you'd want to run it through a full tank of fuel then add it to a second tank before the NCT to get it down and keep it low.

What you've actually done IMO and I mean no offence (and I could also be wrong), is interfered with something that may not have posed any issue at all and made it worse. I'd be very inclined to let the voulentary early test run out now and do another full test with a new inspector in 6 or 8 weeks time and see how the car does. There's probably a fair chance it'll pass as it was only a borderline fail when necked with dipetane and even if it does fail, get a proper diagnosis of the fail, a petrol car failing emissions can often be a simple fix. It'd be a shame to write it off for a set of new spark plugs and an oil service.

Yeah I was thinking that myself that maybe I would've been better just putting it through without the dipetane to give an unbiased indication. However I'd a feeling there might be other things that need doing (which is why I put it in early) and if I'd failed the emissions without dipetane I would've just been back to try it with it in there. Basically what I mean is that if it was just the emissions I'd failed and no further work needed I'd be more tempted to put some work into reducing the readings and giving it another lash. The fact that it's other work and then the possibility of still failing on emissions is what makes me cautious.
I might run some more dipetane for a while and stick it through for a full test in January if I still haven't found something. I'd love to keep it on the road if I can just don't want to let sentimentality get in the way of logic lol