Failed emmisions again
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Looks like it's running rich to me - the CO, though it passes should be closer to 0. I'd invest or borrow a scanner and then monitor Block Learn in 3 or 4 cells. I'm going to guess that you will find #'s above 132 meaning that the PCM thinks it's lean so it's adding fuel A scan will help isolate it - maybe even to one side or if both sides show lean, you can check the integrity of all the vacuum lines, clamp off the air pump and evaporative emission hoses and see what the numbers do.
8th Gear
Joined: Jun 2005
Posts: 8
Likes: 0
From: West Allis Wi.
Hey Blue77, Sorry I didn't get back to you sooner but I've been out of town,the block learn values are the long and short term fuel trims as a whole, which you have checked and I agree 
with SUNCR, they appear to be high on both sides, so lets go back to basics and look for a vacuum leak, hoses, connections,intake manifold gasket,etc.... 
If nothing shows up there I have a few more fuel systems tests that you can do. I don't know where you are in the country but along with the emission testing program does your state also offer free technical assistance at a seperate site, if so you may want to look into that,as I mentioned earlier I am going thru the same thing with may 92' and it has come down to the cats' now, so unless you have a buddy with a dyno and a current gas analyser,this is a great help.
with SUNCR, they appear to be high on both sides, so lets go back to basics and look for a vacuum leak, hoses, connections,intake manifold gasket,etc.... If nothing shows up there I have a few more fuel systems tests that you can do. I don't know where you are in the country but along with the emission testing program does your state also offer free technical assistance at a seperate site, if so you may want to look into that,as I mentioned earlier I am going thru the same thing with may 92' and it has come down to the cats' now, so unless you have a buddy with a dyno and a current gas analyser,this is a great help.
Last edited by gpvette7692; Aug 15, 2005 at 09:28 PM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
I didn't see where you checked the BLM's (Long Term Fuel Trim) and I don't use Datamaster, but it should spit these numbers out. 128 is ideal. Below this is rich, above lean. If you're within a couple of #'s of the magic 128 or at 128, your CAT is probably shot. If not, and the difference is the same on both sides, suspect a vacuum or exhaust leak or something with the air pump or evaporative emissions system. If it's isolated to one side, suspect a plug wire or plug or leaking/sticking injector. Lot's of possibilities, but the #'s can help track it down.
Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 792
Likes: 0
From: Palatine
On startup in open loop, it hickups on launch and has a miss. Once it enters open loop its fine. Would clogged or fried cats cause that in open loop?
From old post....They fluctuated (sp?) alot....
Long term counts L/R their usually within at least 3 counts of each..highs of 160 lows of 115
Short term counts are pretty close it to each other, i think the biggest difference between the left and right bank may have been 10.
Thanks everyone..
From old post....They fluctuated (sp?) alot....
Long term counts L/R their usually within at least 3 counts of each..highs of 160 lows of 115
Short term counts are pretty close it to each other, i think the biggest difference between the left and right bank may have been 10.
Thanks everyone..
Last edited by Blues77; Aug 15, 2005 at 09:58 PM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
160 is incredibly lean and should set a code (115 is just the opposite and should also set a code) - Are you getting these #'s in closed loop? If so, the lean condition could be a vacuum leak or it might be dumping air into the headers when it's warm and a small vacuum leak could cause a stumble or miss when it's cold too. Try to get some steady #'s in closed loop at idle, 1000 rpms, and then 2000 rpms. If those are your BLM's, can't see how it came so close to passing - guess that says a lot about modern emissions controls - but I'd want to fix it if only because it's probably not making all the power it can and your gas mileage is probably suffering too.
Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 792
Likes: 0
From: Palatine
car idles around 550RPM. Full throttle around 2000rpm short trim can hit 140.. Coasting around any rpm it reads usually around 120-124 short trim. So running to rich at coast, and to lean on hard throttle? Ill get some idle numbers tonight.
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
Long term is the BLM and is a better guage of rich or lean.You said it was running up to 160? WOW that is lean.All the above holds true SunCr knows his stuff.It is either an exhaust air leak before the O2's, Vacuum leak or bad O2 sensor.They can be bad out of the box.Datamaster values for the O2's should be around 800 they will jump but should avarage that and be about equal.
Short term numbers will vary especially during acceleration so it is better to look at steady operation at set speeds to see what is going on.
Short term numbers will vary especially during acceleration so it is better to look at steady operation at set speeds to see what is going on.
Last edited by Redeasysport; Aug 17, 2005 at 08:32 PM.
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Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 792
Likes: 0
From: Palatine
Open loop short term stays at 128 at about 1800RPM in Park. Long term open loop at same RPM in park is 127L 128R some of the time, and then drops down to 120 on both sides.
As soon as closed loop kicked in at idle around 750RPM Long term is 127 R 124 L. Around 1500-2300 it probably averages around 135's. Its hard to tell cuz even the L term fluctuate alot. The o2's both seem to be working ok, hittin highs of 800.
Havent found any leeks as of yet. Should I try some of the ford fuel injectors?
As soon as closed loop kicked in at idle around 750RPM Long term is 127 R 124 L. Around 1500-2300 it probably averages around 135's. Its hard to tell cuz even the L term fluctuate alot. The o2's both seem to be working ok, hittin highs of 800.
Havent found any leeks as of yet. Should I try some of the ford fuel injectors?
Last edited by Blues77; Aug 19, 2005 at 05:31 PM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Open Loop BLM's should be 128. Long term trims can fluctuate with changes in rpm but they should be fairly steady at any given rpm.
Looks like it's going rich on the left side at idle, once in closed loop. That might indicate a leaking injector and with it going lean at higher RPM's, I'd guess that might be one of the reasons it's subtracting fuel, (though the fact that it's leaning out both sides, might indicate another problem). I would ohm out the injector coils hot and cold, particularly on the left side. All should be about 17 ohms.
The lean condition at higher rpms could also be a vacuum or header leak, or the air pump is continuing to pump air into the headers, and the first two could cause a miss or stumble. I don't think a check valve is bad since it would be unusal to have both of them fail. You can remove whatever plumbing or hose there is to the headers and make sure there's no air blowing through them in closed loop, but I'd check again for a vacuum leak. Also, take a look at your MAP. Should be about 1.2 to 1.5 at idle. You might also want to get a vacuum reading at idle - just plug the gage into the PCV port - should be about 16 to 19 and steady and I'd do this to make sure there isn't a valve train problem.
Looks like it's going rich on the left side at idle, once in closed loop. That might indicate a leaking injector and with it going lean at higher RPM's, I'd guess that might be one of the reasons it's subtracting fuel, (though the fact that it's leaning out both sides, might indicate another problem). I would ohm out the injector coils hot and cold, particularly on the left side. All should be about 17 ohms.
The lean condition at higher rpms could also be a vacuum or header leak, or the air pump is continuing to pump air into the headers, and the first two could cause a miss or stumble. I don't think a check valve is bad since it would be unusal to have both of them fail. You can remove whatever plumbing or hose there is to the headers and make sure there's no air blowing through them in closed loop, but I'd check again for a vacuum leak. Also, take a look at your MAP. Should be about 1.2 to 1.5 at idle. You might also want to get a vacuum reading at idle - just plug the gage into the PCV port - should be about 16 to 19 and steady and I'd do this to make sure there isn't a valve train problem.