Hello everyone,

I took my Honda for its annual MOT test and it failed on two things:

1- the headlamps aim too low! needs adjusting (how do I do that? )

2- Exhaust emissions carbon monoxide content at idle excessive

This morning, I did put a one shot booster bottle and a bit of super unleaded petrol, took it for a spin on the motorway - but what else I should do?

last week, I flushed the engine oil and filter. aparaently it failed last year on the emission too

(was going very well on the motorway! well impressed! )

any help and advise much appreciated.

 

What year? What country?
I'm guessing UK because you said "MOT" test??

If you tell me "X-plate" I won't know what that means... :P

Some years your Swindon-built car is completely different from our USA Accord. But the headlights are normally aimed by adjusting screws behind the headlamp assemblies. Different years, different locations for the adjusters.

Do you have other emmissions results? Sometimes you can play one against the other. For example if NOx is low but CO is high, you might advance the spark timing. That will reduce unburned HC (including CO) but it'll increase NOx. Some years the spark timing isn't adjustable anyway.

How old are the spark plugs? Hondas seem to work best on NGK plugs.

 

Hi mate,

thank you for getting back to me.

My Honda Accord Vtech SE Executive 2 liter manual is manufactured here in the UK in 1999. (I think that is a fair description )

I have no idea when the spark plugs were changed last, but I will take one out and visually inspect it.

Emission wise, yes it is high on CO2 from the MOT certificate from last year, it had this problem

I just looked at the additive I put in this morning and it is called HOT SH*T (seriously ) and it says it treats up to 15lts! I am sure I had a lot more than 15 liter in the tank and I also missed half of the bottle (forgot that Honda has a safety flap in the tank )

 

I would try a tuneup like Jim said.

You can pull a spark plug to see what shape it is in. I would also remove the distributor cap and see if the contacts inside are worn. Check the edge of the rotor.

Look in the owner's manual for the proper NGK spark plug. You may want to pickup a distributor cap and rotor from the dealership as well

 

USA 1999 Accords have spark timing set by a sensor at the crankshaft. Turning the distributor (like you would on an older car) doesn't change the timing. Does your distributor have slotted holes for the mounting bolts?

Here in USA they called for new sparkplugs every 100k miles (161k km). Suppose that would be the same over there...

Saloon (4-door) is a different car. Coupe 2-door is the same as USA.
Here's a picture of a USA 4-door headlamp assembly. Aiming screw is somewhat visible as a little round **** below the numbers 14 & 15 (not the little clip that 14 & 15 are actually pointing to).


It just occured to me... last time I was in UK the car had a motorized arrangement where I could aim the headlamps up & down with a switch on the dashboard. Is yours equipped like that? Is it working?

 

Thanks for the replies guys.

I located the screws for the headlamps, I turned it a few times clock wise and looked at the wall but couldn't see any change, so turned it lots still couldn't see any difference.

Yes my car does have the switch on the dashboard and you can adjust it to point lower/higher - but the MOT guy said that even when I put the switch to Zero, it is still aiming too low. if I made a **** up, he will fix it with a tenner

My Honda is a 5 door (hatchback) I suppose it is the same as the 4 door saloon.

I'll have a closer look at the distributor tomorrow and will examine the spark plugs as well (hopefully it won't rain as it did the whole day today ) and will report it here.

Much appreciated

 

We don't get the motorized aiming, so I don't know how that affects things. It's only supposed to go lower than normal, when you have luggage in the trunk. Your 5-door headlamps are probably the same as the Swindon 4-door, which means they are a bit different than the USA ones.

Look for another similar adjuster wheel, maybe the one you found is for right-left aiming. In fact, have someone run the motorized up/down settings while you find the motor that's running. THAT's probably operating on the aiming screw that you want. You might have to remove the motor, crank the aim up a bit, then put the motor back.

In fact, the aiming mechanism has to extend inside the headlamp assembly. When we adjust ours, it moves the reflector but doesn't move the outer lense. You could have some broken linkage somewhere???

 

Hi everyone,

Thought I could give you a quick update.

lights are sorted, emission failed again despite taking the car very hot to the test center.

Did a diagnostics test, and it showed that Cat converter was at fault, and so was the O2 sensor! so they said, change both! or at least O2 sensor WTF!!!

This is what I did. Went to local parts shop and got myself this bottle called CATACLEAN - pour couple of them bottles in the tank and put a few liters of super unleaded petrol and off I went to Motorway (freeway/high way) and hammered the old girl for 45 minutes and straight to test center.

Emission result at idle: 0.03 !!!!! what a difference!!!!

so I my Honda is back on the road for the next 12 months.

Thanks for your support guys.

 

Congrats....how did you sort out the lights? Might help someone in the future.

 

gave a tenner (£10) for the MOT test man, and he adjusted it from them white plastic adjuster on top of the head lumps, under the bonnet. I had set them way too high

so when you adjust the lights with a screw driver, they do actually aim up or down, it just that I couldn't see the movement. So I kept turning and turning