Emissions

[Ricker]

In the wonderful state of Colorado cars have to be emissions tested. Long story short my DeLorean did not pass. If failed on HC PPM 848.4 (Limit 220.0) and CO% 4.65 (Limit 1.20).

The engine has 9,700 original miles and almost everything is 32 years old except the O2 sensor - brand new. It does idle a bit rough at idle but runs good.

Not even sure where to start or when these readings are out what to look at.

Any suggestions? I'm not real keen on taking it to some garage unless it is the last choice.

[Chris 16409]

Take a look at my emissions report. I have a Stage 1 exhaust which may not run as clean as a stock system, and I am way low on both of those tests. In fact in CA we have much stricter limits on CO and HC.

36275

My highest CO was 0.1 and highest HC was 43. I would guess you either don't have a catalytic converter or it has gone south. It could be your mixture is not set correctly, or your lambda system is not functioning right.

[hmcelraft]

Looks like you have a fuel management issue. I can think of numerous issues that could cause those high readings and the car still seem to run ok but, it is apparently getting too much of it (or some really weak cylinders). You really need to find someone with the skills to diagnose the fuel system and maybe the engine for you. I would say it needs to be a hands-on thing. A classic car shop might be able to help. There are a number of cars, mostly European 70s-80s, that used the K-Jetronic systems. Properly tuned and fairly solid DeLorean motors burn very clean even with ethanol.

[Ricker]

Looks like you have a fuel management issue. I can think of numerous issues that could cause those high readings and the car still seem to run ok but, it is apparently getting too much of it (or some really weak cylinders). You really need to find someone with the skills to diagnose the fuel system and maybe the engine for you. I would say it needs to be a hands-on thing. A classic car shop might be able to help. There are a number of cars, mostly European 70s-80s, that used the K-Jetronic systems. Properly tuned and fairly solid DeLorean motors burn very clean even with ethanol.

I figured it is the fuel injection with the hydro-carbons being so high. I had some problems with the cold start valve sticking. I pulled it out and cleaned it. I think it is doing what it should be. Maybe it is causing the HC being so high.

Before I do anything I have plans this winter to replace the vacuum hoses, spark plugs, wires, rotor cap, filters, oil and then get the fuel injection checked. Probably should get the compassion checked while I'm at it. I am considered sending it to Specialty Auto to have it re-build.

I'll have to check to see what the catalytic converter does and how it effects the CO (and HC). Exhaust is so rusted I may need to replace the whole thing if it comes to that.

[DMCMW Dave]

Probably should get the compassion checked while I'm at it. I am considered sending it to Specialty Auto to have it re-build.
.

When did S-T start rebuilding compassion?

[Ricker]

When did S-T start rebuilding compassion?

Maybe I am remembering wrong but at one time I thought when talking with him that if I sent the fuel injection system he would rebuild it. Didn't get any other details at the time. Another thing to check on for this winter projects. The quantity of projects just seem to increase weekly. But there are still a number of weeks left to enjoy driving.

[mluder]

Pull the catalytic converter... It's probably useless and needs to be replaced.
When I got my car 5 years ago it had about 9,000 miles on it. Also wouldn't pass emissions.
I pulled the cat off and the media inside was just a pile of rubble - completely ineffective.

Cheers
Steven

[PJ Grady Inc.]

I figured it is the fuel injection with the hydro-carbons being so high. I had some problems with the cold start valve sticking. I pulled it out and cleaned it. I think it is doing what it should be. Maybe it is causing the HC being so high.

Before I do anything I have plans this winter to replace the vacuum hoses, spark plugs, wires, rotor cap, filters, oil and then get the fuel injection checked. Probably should get the compassion checked while I'm at it. I am considered sending it to Specialty Auto to have it re-build.

I'll have to check to see what the catalytic converter does and how it effects the CO (and HC). Exhaust is so rusted I may need to replace the whole thing if it comes to that.

The only easy thing you can check would be to see if someone removed the original CO adjustment plug. If they did and played with the enrichment in the hope of more power you can bet they cranked it a turn or two to the right which could easily cause the issue you're having. In the event that it's not that simple you might consider bringing it to us as I'm within driving distance and have 34 years of engine tuning experience on the PVR. Just a thought for your consideration as Texas is a lot further away than Long Island. Your engine will pass any emmissions test easily with the proper tuning.
Rob

[Delorean Industries]

If your converter is no existent or destroyed high flow direct fit replacements.

http://www.deloreanindustries.com/19-high-flow-converter-stock-exhaust/

[Ricker]

The only easy thing you can check would be to see if someone removed the original CO adjustment plug. If they did and played with the enrichment in the hope of more power you can bet they cranked it a turn or two to the right which could easily cause the issue you're having. In the event that it's not that simple you might consider bringing it to us as I'm within driving distance and have 34 years of engine tuning experience on the PVR. Just a thought for your consideration as Texas is a lot further away than Long Island. Your engine will pass any emmissions test easily with the proper tuning.
Rob

Rob:
I'm going to try the catalytic converter first but if that is still not getting it I will be getting a hold of you and guess I will be visiting Texas. But it won't be till late winter next year (March or so).