1997 Ford Escort Failed NOx Emissions ( Daughter's Car )


Old 07-10-03, 02:27 PM
Visiting Guest
Posts: n/a
Lightbulb 1997 Ford Escort Failed NOx Emissions ( Daughter's Car )

Hello everyone, Just wanted to let you know that Im a new member here, And I see that you have very useful information here.
The story is: I brought my daughters 1997 Ford Escort to the State Inspection Station here in New Jersey, And the car failed for emisssions, ( NOx ) The standard reading is 756, and the reading on the emissions test was 1234, Results was (failed), But eveything else passed. Any ideas of what I can do would be very much apprecated. I was thinking maybe the EGR Valve, The car always passed inspection with no problems, When We bought the car, They told us you do not have to tune up the car for aleast 100,000 miles or 10 years. But who really knows for sure.
In my younger day's I used to rebuild motors until I got hurt. But they didn't have all the fancy componets, on them, Like they do now, But does where the days.

Thanks For All Your Help:
New Jersey
Sponsored Links
Old 07-10-03, 04:14 PM
Visiting Guest
Posts: n/a
Make sure both the cooling system and EGR system are working properly.

NOx is combustion chamber temperature related. You most likely have a bad EGR valve or the secondary AIR system (if equipped) is not working.

Start with the EGR system.
Old 07-10-03, 05:22 PM
Visiting Guest
Posts: n/a
i don't really speak 'ford' but there are two major things to check, if it does indeed have an egr valve, it must be working fully. pull up on the valve diaphram(or apply vacuum to it), car should almost immediately stall or run very rough, if it has no affect--- the passage is clogged, i've seen a lot of this on other makes lately, it depends on the engine design how easy it's going to be to clear it out(i use a coathanger and parts cleaner along with compressed air). 2nd egr test, make sure as you rev the warmed up engine that the valve is getting vacuum to it, some manufacturers block this vacuum signal until the tires are turning(those i check with jackstands under the axle). some engines have an external egr tube, after a short drive, if this tube is very hot---that's a good sign it's all working.

second very important factor is ignition timing, if you even have a distributor(i don't know) back the timing off at least 8-10 degrees from spec, the NOx will drop dramatically.

one other thing to check is if the car is running 'hot' a fully warmed up engine(long time idling with a/c on) will be prone to having high nox, wait for the coolest day that you reasonably can, then go, shut the engine off in the line too.

my car passed on a very hot 90 degree day(at the state) by 1 nox, the next time on a cool 65 degree day it passed easily(and i do inspections too)

i'm sorry i've never worked on an escort, so maybe these tips might not apply to you, but hopefully someone with some more experience will chime up, if they do apply, then i think they will help you get right through

also call the dealer, see if you have any outstanding recalls, i know of an import product that had a 'high nox' recall---needs a new computer to fix it, timing isn't adjustable
Old 07-11-03, 06:59 AM
Visiting Guest
Posts: n/a
True----if the shop doesn't use a fan to push air through the condenser and "cool" things down, you could get this.

I remember seeing that part of the NYS dyno setup should be good airflow or a good fan. That will ensure that air is rushing into the vehicle while its tested. This will help .

My mother brought our 1993 Saturn to get inspected on Tuesday and it was close to 100 out. I noticed that the NOx was a little higher than it probably would have been due to the heat. However, it was well within spec, I installed a new EGR valve and a bunch of sensors as most were original on it .

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes