hey-my 2001 ford escape had an engine light - i read the code as P0402-excessive emissions flow...erased the code but when i went to get inspected it was rejected because they couldn't read the emissions data? this happened after the battery had to be replaced cause the truck sat unused all summer...drove it 350 miles and still rejected for inspection after I erased the code...inspection report indicates it was rejected due to not being able to read the catalytic converter and gives a code range which does not show up on my diagnostic code reader for my car...any ideas? how expensive is the issue that needs to be repaired? can I do it myself? hate to drop $$ on having the garage "diagnose" the problem with their computer or is that my only choice?

 

Do you have an AutoZone nearby? I'd run it by them and see what their machine turns up.

 

I posted this right after you made this thread, but FTE had a hiccup and went down when I clicked the submit button. My original post got eaten by the internet.

Here it is again for you. This is a pretty comprehensive break-down for you.

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P0402 OBD-II Trouble Code
Technical Description Exhaust Gas Recirculation Flow (EGR) Excessive Detected

What does that mean?
EGR stands for Exhaust Gas Recirculation. It is part of the vehicle emmissions system, and is used to reduce combustion temperature and pressure to control Oxides of Nitrogen. There are generally three parts to the EGR system: the EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0402 code means that OBD detected an excessive amount of EGR.

Symptoms
You may notice drivability problems such as the engine may surge off idle. There may also be other symptoms.

Causes
A code P0402 most likely means one or more of the following has happened:

• [*]

Possible Solutions
With a P0402, it is common for people to replace the EGR valve, only to have the problem return. The most likely solution is to replace the DPFE sensor.

• [*]

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Source: OBD-II Trouble Code: P0402 Exhaust Gas Recirculation (EGR) Flow Excessive Detected

That should help you narrow it down.

If it were me, start with the least expensive way to fix the problem. Take the EGR off and clean it.

I did this to my Lightning one time and I found chunks of carbon that had broken loose and was clogging the "throat" of the intake where the EGR mounts to it.

Stewart

 

You're failing because your readiness monitors aren't set.

OBDII emissions testing these days has to verify that

*NO CODES ARE SET

--AND--

*ALL READINESS MONITORS ARE SET TO 'READY'

The second may vary from state to state, for example, here in Missouri, we're allowed 2 unset monitors if 1996-2000, and one unset monitor if 2001+.

When you are clearing your P0402 code, it also resets all of the monitors to "NOT READY". This is why you are failing.

It takes a bit of driving to reset the monitors. The monitors each set to 'READY' once the computer has had a chance to run the appropriate tests, and determine if there is a problem or not in that system.

So, being you have a problem in your EGR system (Most likely a bad DPFE sensor), once you set your EGR monitor, your P0402 will appear again, and you'll fail the test anyway.

You need to FIX the problem, and then drive the car a couple of days to set the monitors before having it reinspected.

Many parts stores and shops will check your monitors for free, you'll just need to call around.

 

That's a P1000 code. Unless I read his post wrong, that would have been cleared by his driving 350 miles.

Plus, the P1000 code is a commonly read code and should show up on even the cheapest diagnostic code reader.

What he describes below doesn't sound like the P1000 Readiness code being set from clearing his DTC.

Then again, maybe I'm reading his post wrong.

Stewart

 

his driving 350 miles may or may not set all monitors. each monitor has a specific "drive cycle" characteristic. If his driving was "all city", at speeds less than highway for a "certain amount of time", then it is quite likely the monitor will NOT be set. It would appear to be the case assuming he hasn't "screwed" around in the engine bay... "accidentally" tugging sensors wires and such.

As mentioned, just erasing codes ain't going to solve your problem. You need to address the initial issue (ie. EGR stuff). You also need to do a little reading on OBD stuff before you "play" around some more.

PS. Your issue with your "cat not be readable" might be a wiring issuing.
PPS. what was the code that the inspection station indicated to you... the "gives a code range" doesn't help us help you much.

 

I'm assuming that by his "cat not being readable" he meant the CATALYST monitor wasn't set to READY.

Different states and counties have different rules as far as readiness monitors go. Usually, gentle cruising at 50-55 for about three miles or so is enough to set MOST of the monitors on these, but not all of them. I've learned that if there is a problem, even a borderline condition, it can sometimes take much, much longer.

Some monitors even require multiple drive cycles (Start vehicle cold, drive it appropriately, let it cool several hours, then start cold and do again).

Even driving it 350 miles won't necessarily set certain monitors. This can happen if it is too cold outside, if the fuel level isn't in the correct range, if the vehicle is driven hard or too fast or too slow, etc. I've also seen vehicles the a thermostat stuck open that didn't want to set monitors because the engine didn't want to heat up to the proper temperatures. Also monitors typically require the A/C to be OFF during the drive cycles, so if it's on this can prevent monitors from being set.

I think we're going to need some better info here from the original poster...