de-cat exhaust

tooler7

well guys was looking at a crx del sol sir 92 only prob is it has a de-cat exhaust on which also causes the engine light to turn on while driving and the nct is up in feb 09 the owner claims he passed the nct no problem with it on but i dunno is it to risky or would it be ok on the nct anyone with any experience with this sort of thing???

Darragh29

tooler7 wrote: »

well guys was looking at a crx del sol sir 92 only prob is it has a de-cat exhaust on which also causes the engine light to turn on while driving and the nct is up in feb 09 the owner claims he passed the nct no problem with it on but i dunno is it to risky or would it be ok on the nct anyone with any experience with this sort of thing???

First of all tooler, excellent car! Would love to have a del sol, maybe one day, anyway...!!!

There is no way that car is going to pass an NCT with no cat. The problem is easily resolved, just put a cat in. I'd happily buy that car once I knew what I was getting into, which is a few hundred quid to get the CO and HC to be within NCT limits because you'll have to fit a cat. I had a customer with a vvti civic which is basically the same set up as you have in the del sol, who was given all the same promises about emissions and passing the NCT. A cat is there for a reason and that is to recombine products of combustion into CO2 and H20 while minimising CO.

Lovely car, take it with a cat or without one is my best advice, just don't let some loo laa talk ****e to you about waltzing through the NCT when any mechanic here will tell you the opposite. If he thinks the car will pass the NCT without a cat, just bring it for an emissions test. It will cost you no more than 50 Euro but you'll see that I'm stating fact here...

Clarifying for limits... Just recalled that this car doesn't have to fall within 0.3% or 0.5% CO limits, or fall within less than 200 PPM HC limits, based on being exempt from "standard" NCT emissions limits due to age of car, pre 1993...

tooler7

thanks a million darragh sounds like you know what you are talking about ill get back to him anyway i also heard that because its a 92 it doesnt hav to hav a cat exhaust that only came in, in the mid 90s not to sure bout that though but it is a great car and hopefully soon enough i will own one

Darragh29

Now he might have a point there because the limits changed around 1992. I had this once with a customer with a Mk2 Golf who had emissions results that made me shudder but the year of his car meant he had to deal with a very relaxed set of criteria when it came to the nct...

It seems that you will fit into this lax criteria, based on the data below which is taken from the NCT manual, available through their website:

For vehicles first registered on or after 1st day of October, 1986, up to
31st December, 1993, the carbon monoxide content at idling speed is
more than 3.5%.

For vehicles first registered on or after 1st day of October,1986, up to
31st December, 1993, the hydrocarbon content at idling speed is more
than 750 P.P.M.



Check that your emissions without a cat fall within the above criteria. If they don't, they ought to with a cat fitted to the car, because the above limits are really made to suit a market when cats were just coming into fashion....

scottledeuce

I think every car post 87 or 88 must have one by law..

The car will be off the scale emissions wise as well for the test so you will need to fit a cat although sourcing one shouldnt be a problem I'd imagine as the del sol shares a lot of parts with civic models.

I would be more concerned about the engine light as if the decat is setup properly with o2 sensor rewired/inserted it should show no warnings, I have my fto decater for years now and never had an issue bar putting the cat back in for the test.

Avns1s

scottledeuce wrote: »

I think every car post 87 or 88 must have one by law..

1993 IIRC it became mandatory to have a cat!

Max_Damage

scottledeuce wrote: »

I think every car post 87 or 88 must have one by law..

No, my '90 Micra doesn't have a cat.

As the previous poster said, it was '93 before they became compulsory in the EU. They were compulsory in the USA since the '70's though.

tooler7

thanks a million guys was doing some research and seems like it would be ok for the nct cause its not that loud either but im still worried about the engine light does anyone have any experience with that and why the exhaust causes it to be on and would it be possible to get the light off with a service

Darragh29

tooler7 wrote: »

thanks a million guys was doing some research and seems like it would be ok for the nct cause its not that loud either but im still worried about the engine light does anyone have any experience with that and why the exhaust causes it to be on and would it be possible to get the light off with a service

I've seen this before a few times. You'd have to get it hooked up to see what's causing that light to come on. Throw up a few pics of your crx when ya get it!

scottledeuce

Avns1s wrote: »

1993 IIRC it became mandatory to have a cat!

I stand corrected,

About the light, the most likely reason it's on is that the exhaust sensors are showing incorrect readings,

This will be the case if there is a sensor further down the exhaust as the cat absorbs a lot of the heat which a decat wont.

After getting some advice my solution was to simply remove the bulb although I've heard of people adding resistors to the circuit and such as these sensors sometimes have a real bearing on performance (not in my case) but what can happen is the engine ecu may scene more hydrocarbons in the emissions and so think the engine is running rich and compensate with less fuel.

Thats my two cents on the matter,it's bases solely from personal experience but I doubt the above would have much bearing on a 92 crx engine

Darragh29

scottledeuce wrote: »

I stand corrected,

About the light, the most likely reason it's on is that the exhaust sensors are showing incorrect readings,

This will be the case if there is a sensor further down the exhaust as the cat absorbs a lot of the heat which a decat wont.

After getting some advice my solution was to simply remove the bulb although I've heard of people adding resistors to the circuit and such as these sensors sometimes have a real bearing on performance (not in my case) but what can happen is the engine ecu may scene more hydrocarbons in the emissions and so think the engine is running rich and compensate with less fuel.

Thats my two cents on the matter,it's bases solely from personal experience but I doubt the above would have much bearing on a 92 crx engine

Yeah... :rolleyes::rolleyes::rolleyes:


If there is a lambda sensor downstream of your cat or where your cat should be, this could be the cause of the problem, but the only way to know is to hook it up and pull the fault code. Forget about pulling out bulbs and resistors and all that crap!

ytareh

1993 and older do not need car.94 and newer do...Simple as that ...some very erroneous however well intentioned info being doled out here!

tooler7

thanks a million guys for the help and the info hopefully anyway it will pass the nct

xt40

the nct fellas ignore warning lights and go by their own equipment/observations. as previously mentioned, its a 92 so the criteria are more relaxed bring it in , it might pass and if not it will only cost you 27 euro more for a retest

awhir

Darragh29 wrote: »

First of all tooler, excellent car! Would love to have a del sol, maybe one day, anyway...!!!

There is no way that car is going to pass an NCT with no cat. The problem is easily resolved, just put a cat in. I'd happily buy that car once I knew what I was getting into, which is a few hundred quid to get the CO and HC to be within NCT limits because you'll have to fit a cat. I had a customer with a vvti civic which is basically the same set up as you have in the del sol, who was given all the same promises about emissions and passing the NCT. A cat is there for a reason and that is to recombine products of combustion into CO2 and H20 while minimising CO.

Lovely car, take it with a cat or without one is my best advice, just don't let some loo laa talk ****e to you about waltzing through the NCT when any mechanic here will tell you the opposite. If he thinks the car will pass the NCT without a cat, just bring it for an emissions test. It will cost you no more than 50 Euro but you'll see that I'm stating fact here...

Clarifying for limits... Just recalled that this car doesn't have to fall within 0.3% or 0.5% CO limits, or fall within less than 200 PPM HC limits, based on being exempt from "standard" NCT emissions limits due to age of car, pre 1993...

getting a small bit confused ?