Hydrocarbon Count - MOT time

[E30Adam]

MOT time is here and things aren't looking good. My HC count is over the limit, tollerance is 1,200ppm and mine came in at 1,595ppm.

My car was rolling roaded and remapped by Bexleys about 6 months ago, maybe less, would the high reading be something to do with their tuning because my car is now out of action until I can get this sorted out. It has a Schrick 284/272 cam which probably doesn't help matters but I need to know it's to do with the remap so I can call them up to sort it out if it is.

It also has a MAF conversion so when it's cold it's running pretty rough anyway because there's no air temp sensor so they probably tested it before it reached full operating temp. I have an air temp sensor here to fit but I think Bexleys should have done the job properly in the first place.

Thanks

[Karan]

adam mine gave a count of 250ppm ,

so i guess ures may have been cold... or it could be the mixture at idle

Karan

[E30Adam]

I reckon it must have been cold because the car was stood overnight and was only driven about 2 minutes up the road. Emmissions tests are carried out at about 2,500 - 3,000 rpm.

[nadz325i]

I reckon it must have been cold because the car was stood overnight and was only driven about 2 minutes up the road. Emmissions tests are carried out at about 2,500 - 3,000 rpm.

mine was done at idle, passed to, dont knw what the readin was tho,

i always get the engine operating temperature before i get it done, must be because its cold.

[Russ]

Im sure there is an idle test (at idle) and a "fast idle" test (2500 - 3000 rpm) or something....

Have you got a friendly tester? Or one who might make a mistake an accidentally put the probe into a ford ka? That would be a grave error....

[SCOTT325SE]

Why is it that so many people are having troubles or "concerns" with the work that Bexley have done in the last 12 months eh? There was a time when the South Coast Massiv thought the sun shone out of the roller shutter doors at Bexley Motor Works! Now though, everyone seems to be having problems! Maybe Bexley arent as good as they have been talked-up to be!

Examples - Dales £4000 or £6000 engine map etc, he wasnt happy with that (for bloody good reson too)
Adam, you have Emmissions worries! I mean, FFS, thats a basic pre-requesit when doing tuning to a car - its got to keep the car legal!

Maybe Bexley should be called Bodgely Take Lots of Cash Motor Works, coz thats all they seem interested in is taking your cash and car, parking it outside their garage, and charging you thousands of pounds for very little work! Admittedly, ive never BEEN to Bexleys, but BHP, emmissions and Torque figures dont lie.... If they cant get an engine to perform well AND keep it within MOT guidelines, maybe they shouldnt be doing it at all!

Opinionated rant over. I dont mean to get peoples backs up with what i say, but im just speaking from a 3rd person perspective - Id be MIGHTY p1ssed off if i shelled the sort of money that some guys do, only to get sh1te results and a car that cant be driven come MOT time.

[Ant]

1200 PPM, test at idle following an engine purge, ie up to temp and run @ 2K for 30 seconds then test. it is permissable to test @ up to 2K for then non cat test.

either way Adam this needs looking at, pollouter

[E30Adam]

1200 PPM, test at idle following an engine purge, ie up to temp and run @ 2K for 30 seconds then test. it is permissable to test @ up to 2K for then non cat test.

either way Adam this needs looking at, pollouter

Yeah definately mate, I know the HC's should be around 200-300 for a normal reading.

Would you say this is something to do with the remap because I need to know before calling them up really.

[Demlotcrew]

thats high, is it burning oil?

[Andy335Touring]

Is it worth you trying Dale's man for your remap ?

What does high HC's represent ? Unburnt fuel ?

[E30Adam]

Nope not burning a drop of oil Demlot.

I'm not sure what the HC's represent although I think it may be unburnt fuel.

[Dom]

could the exhaust be coked up pushing the figure adbnormally high?

[E30Adam]

could the exhaust be coked up pushing the figure adbnormally high?

Definately not, it's almost a brand new system.

Just found this on HC's:

Hydrocarbon pollutants escape into the air through fuel evaporation. This can occur on a hot day or if the engine is hot whilst running. Lots of the vapours collect in fuel tanks and are then force out when the tank is filled with liquid fuel. It is estimated that over 50% of all hydrocarbon emissions into the atmosphere are from automobiles. The problem with the emission of hydrocarbons is that it forms particles and also leads to the formation of ozone.

[Demlotcrew]

My M42 (missing two cyl) has a count of 274.

[E30Adam]

My M42 (missing two cyl) has a count of 274.

Good for you

Any idea how I can sort mine then????

[Demlotcrew]

Well ant pissed about with my AFM on his magic machine. I think it might be a Remap for you matie boy.

[boybimmerm3]

adam, what is your c/o reading? and your o2 level? if you have an air leak the ppm's will rise too.

[E30Adam]

adam, what is your c/o reading? and your o2 level? if you have an air leak the ppm's will rise too.

Both of those passed mate, no air leaks, everything on the engine is pretty much new.

CO: 3.5% tollerance - Mine was 0.43%
HC: 1200 tollerance - Mine was 1595ppm
Idle Speed: Pass
Smoke Level: Pass

Thats all the info on there, no mention of O2

I think it's going to need mapping again, Bexleys can have it back to do a proper bloody job!

[Ant]

wonder what the idle lambda is ??

with that Co I suspect its lean at idle, if the idle co was 1.0 I suspect the HC count would drop considerably dude

lean mix causes unburnt fuel , basically theres not enough fuel to form an effective "bang" so a lot of it goes straight out the exhaust again.

you done the IAT mod yet Ads ??

[E30Adam]

I havent got round to doing the IAT mod yet, it's still sitting on my desk here.
I'm a bit reluctant about drilling a hole into the MAF but I guess it needs doing.

Do you reckon I should tweak up the CO at idle, hopefully this might bring the HC's down to a respectable level.

Ah, just had a thought, there's no idle mixture screw now because I have the MAf and no AFM, how can I adjust it Ant?

[boybimmerm3]

if the c/0 reading is low that could indicate an air leak. if you just adjust the c/o up somehow all you will do is just make the ppm's worse. have you tried spraying wd40 or similar around the inlet gaskets etc to see if the engine note changes? does the car run at all rough or is that all ok. i had a e30 which had a dodgy injector and that can cause high ppm's also. well there is some more for you to look at. let me know if you need more ideas.

[E30Adam]

if the c/0 reading is low that could indicate an air leak. if you just adjust the c/o up somehow all you will do is just make the ppm's worse. have you tried spraying wd40 or similar around the inlet gaskets etc to see if the engine note changes? does the car run at all rough or is that all ok. i had a e30 which had a dodgy injector and that can cause high ppm's also. well there is some more for you to look at. let me know if you need more ideas.

Seriously mate, pretty much the whole engine bay is brand new, it definately hasn't got an air leak.

It runs rough on startup but thats because I have a MAF instead of AFM so there's no IAT sensor. Once warm it runs fine apart from the slightly lumpy cam. My reckoning is that they probably tested it when it wasn't properly warmed up. I think it's going to need mapping properly to sort it.

[Ant]

Adam:

the IAT can go anywhere in the intake tract, before the MAF in the filter would work well ,it just needs to be in the flow thats all

To get a pass fit a bleed screw for an aquarium air pump into the vacuum line from plenumn to FPR, that will bleed air in and might get you the ticket.

Best bet, REMAP and go one better and get it closed loop controlled dude.

[E30Adam]

Adam:
get it closed loop controlled dude.

In English LOL

Never heard that before mate, could you explain pls.

I'd like to take it back to Bexleys and tell them to fix it but I've lost my confidence in them and might just take it straight to Dales place for a new remap. Maybe they'll extract a bit more power for me!!

[Simon13]

dude where's your heat sheild for that air filter?!

[E30Adam]

dude where's your heat sheild for that air filter?!

Thats an old old pic, I don't have that crappy setup now!!

[Ant]

Closed loop in laymans, @ idle with TPS in closed position the ECU will control the idle mixture via a lambda/02 sensor ie CO and HC as per factory spec for cat equipped cars

I'm sure you could retrofit the probe to yours and plug straight into the ECU, the unichip is only modifying the signal from what was the AFM loom into load info the ECU can understand

[Karan]

ant for us thickos....isthe closed loop lambda working throughout the rev range at all loads or jus at idle??

cheers
Karan

[E30Adam]

The lambda probe goes into the exhaust manifold, am I right? There are 2 bolts in the top of mine which appear to be blanking plugs, coud this be where it goes? I guess I would then just run a wire to the spare connector?

Any ideas where I could put the IAT sensor because there isn't much room, my filter goes straight onto the MAF. I could silicone it into the rubber elbow?

[Ant]

as far as I'm aware the e30 only has closed loop @ idle.

the AFM and TPS give load info to the ECU once off idle dude, later more modern syatems enjoy a lean cruise facility and are true closed loop

if the throttle is held @ a setting for a period of time the ECU can reduce injector duty to the onset of pinking, this is sensed by a knock sensor and then the ECU will increase the fuelling to the point where the pinking just stops, saves £Â£ on fuel and emissions, the price is marginally slower response to a heavy acceleration, were talking 100s of a second though

Cant be done on M20 engines,, no provison for a knock sensor on the stock ECU and loom, could be done VIA Emerald etc and I consider such a setup vital for a turbo conversion

Edit: Adam you can add into the hose no worries dude, cut a tiny hole and superglue it in there, just make the hole a tight fit