'94 LWB, passed the 2500 rpm test, failed the idle test.

Shows up as HC (PPM) 574, with an allowable limit of 220.

Causes? Solutions?

The testing guy recommends changing the oil, says that might help.

He mentioned the dreaded Sea Foam. I cringed and said I wouldn't use it. He doesn't blame me.

Any ideas?

:shaking:

Any other problems with the rig? My pappy had a bad coil on his 95 disco that caused all sort of hell, including emission hell.

I suppose if it was throwing codes, you'd know...

How old are the CATs? It seems like ~100,000 miles seems to be the life of catalytic converters. At least, that is my observation.

Why hate on seafoam!!?? I've never had any problems with it.

I've put 93 octane gas in cars that have been iffy on emissions. Seems to help.

I reckon check all your vaccum hoses and fuel lines. A buddy of mines 85' firebird was a bitch to get emission passed. He replaced all the fuel lines and vaccum hoses. Damn thing passed with flying colors after that. I never thought that would do anything, but it worked like a champ.

Possibly fuel injectors need to be cleaned??

Run it aorund in second gear for half an hour. While it's still hot, take it into the testing station.

You might just pass.

Did it pass inspection in Oregon? If so, what has changed?

20% Methanol

'94 LWB, passed the 2500 rpm test, failed the idle test.

Shows up as HC (PPM) 574, with an allowable limit of 220.

Causes? Solutions?

The testing guy recommends changing the oil, says that might help.

He mentioned the dreaded Sea Foam. I cringed and said I wouldn't use it. He doesn't blame me.

Any ideas?

:shaking:

Is your air-filter clean? One year my '83 failed...changed oil and replaced air-filter and it passed.

So...why no on the Sea Foam? If you're afraid what the neighbors will think about the giant smoke screen, do it at night!!!

I run acetone in every tank. Use a 1:510 ratio. This will lower emisions, increase MPG, extend oil life and extend engine life. The acetone allows for a more complete burn in the combustion chamber. They have been running acetone in cars since the 30's and there is no harm to the internals. I use it in all of my vehicles including my bike. Better performance also. Just a little know fact that needs to be know about. Good luck

check the vacuum line on the pressure regulator, mine cracked and it ran very rich as a result.

How old are the o2 sensors?

My 95 passes w/ no problem and gutted cats. I replaced the o2 sensors w/ nissans around 50k ago.

Replaced both 02 sensors, cleaned out stepper motor.

Hydrocarbons didn't change at all at idle, infact increased by 2-millionths (yeah right...some change). Interestingly enough, they did get cut in half on the 2500 rpm test. 220 max, mine read 59. At idle though I'm still at 357 with 220 max.

Plugs? Wires? Bad injector somewhere?

This is really driving me crazy.

:mad3:

Return to baseline. Plugs, wires, cap/rotor.

There really isn't a whole lot more that can be done without looking at realtime data to insure that the oxygen sensors are changing state as specified, that injector pulse width is responding along with the oxygen sensosr, that the MAF sensor is doing it's job, along with TPS.

IF, and only IF the EMS is doing its job, you might need some injectors. You're obviously running rich at idle. If th EMS can't reign in the injectors, it pretty much has to be a leaking injector or excessive fuel pressure.

Maybe check the base idle?

Are all crankcase vent and vacuum hoses OK? I seem to recall a good local mechanic who solved a lot of low rev issues by replacing crank vent hoses and clearing out the oil trap.

Are all crankcase vent and vacuum hoses OK? I seem to recall a good local mechanic who solved a lot of low rev issues by replacing crank vent hoses and clearing out the oil trap.

He claims to have already done this, and more.

He claims to have already done this, and more.

All of the hoses and 'T' piece are 20K miles new. I just cleaned out the flame trap...was kind of gooey in there.

Next are plugs/wires. I don't think that they're *that* old, but I'll do them anyway. Looked at the cap, looks good and clean, it's a blue one. Rotor was a little black, cleaned it up and put it back in.

So for fun I reset the base idle...found out it was set WAY too high. I cranked down the screw all the way clockwise before the idle went down. Nearly 2 full turns. Idles like a champ now.

Would that have had anything to do with the idle being too rich?

It might well have been the culprit. Go get it tested and then fix the fuel pump wiring so Pendy doesn't give you Hell about it!

was this the culprit

was this the culprit

NO, it wasn't the culprit. I'm still chasing it.

I'll do a more complete write-up when I have the energy.

Have you set your base timing? Does it have an exhaust leak before the cats? Check for vacuum leaks at at the intake manifold. Check air intake hose for holes. If nothing, perform injector leak down test by priming pump and pinching off fuel return. Have your pressure gauge on and watch. Pressure should hold. Also does it have any drivability concerns? Rough idle or stumbles. Good luck

Does it have an exhaust leak before the cats? Check for vacuum leaks at at the intake manifold. Check air intake hose for holes.

Vacuum leaks would result in a lean condition, not a rich condition...

Which will cause the engine ecu to command to go rich, Via the O2 sensors.

Could there be a 'vacuum leak' caused by the plenum to not be properly sealed? I could double-check it.

run it low on fuel
throw in a litre or so of Rubbing alcohol
take test/refill with petrol and away you go

the alcohol will get it through no probs

Holy crap...this year it failed AGAIN! This time the idle passed and the 2500rpm test failed! ARGGHHHHH!

Time to change the oil, check the filter. 02 sensor still not working, but it's not that far from passing. Hopefully that and a tank full of ethanol will work. :mad3:

02 sensor still not working,

For the love of God would you fix the wiring to the sensors?

Your fuel economy will likely improve too!

You still haven't answered my question.

How much E-85 can I put in my tank before my engine explodes...and will it help to pass the sniffer test? :flipoff2:

You still haven't answered my question.

How much E-85 can I put in my tank before my engine explodes...and will it help to pass the sniffer test? :flipoff2:

I've run mine on half E-85, half regular gas with no problems but reduced fuel economy-don't know how much it will help, probably won't hurt. Thinking back, I wonder how much of the diminution in fuel economy was due to the tranny being worn out.

sorry to hijack, but what would it take to run e-85 in my 95 disco? my understanding is that the ENTIRE fuel system has to be switched to something that the ethanol won't corrode? does that mean injectors as well or just the lines, fuel pump, and fuel rail, etc?

to add to pauls comment i have heard most people who want to run the e-85, do the 50/50 blend without issue.

Well, I just got back from the Spiffy-Lube and the truck passed. I don't know if it was the oil change or the E-85 that did the trick. The CO2 emissions were measured at 0.00 which was different from yesterday, a 1.75.

But, I have my certificate and I'm heading to the DMV! Woohoo!!!!

EDIT: I think I'll go back to running on straight dino-oil. I want the price of my milk and steak to come back down. GRRRRR.

My old Bronco would have probably 2 gallons of gas and 1 gallon alcohol for the emissions test and didn't seem to suffer. In fact I have slowly been pouring a 4 gallon E-85 to 1 gallon gas mix into my tank on my RR to get rid of it. I had to mix it for the fuel cell on my race car to get rid of all the water that had condensed in it.

EDIT: I think I'll go back to running on straight dino-oil. I want the price of my milk and steak to come back down. GRRRRR.

Nooooo, high corn prices are a good thing :)

Well, they are in Iowa. At least except for the farmers complaining about having taxable income !

KAA