2000 Windstar p1151, cant pass emissions

[ditchmagnet]

I am getting a p1151 code, (which is ho2s lack of switching bank 2), and have replaced the MAF with a used one, changed the plugs, cleaned the orifices under the intake plenum, new air filter, tried to check for vacuum leaks. The car runs fine though, and I left the battery disconnected a few times to reset the pcm, but the code keeps coming back.

What else should I check? Should I put in a new o2 sensor on bank 2 there or something else?

EDIT:
I just got back from autozone and got the codes checked again. I am getting 3 codes:
P0171, P0174, and p1151

Now when I took apart the intake plenum it did have some green sleeves on it, so that shouldn't be the problem right? and I did scrape those orifices while I had it apart. So now what?

[12Ounce]

You still have a vacuum leak somewhere, ... and that needs to be addressed before tackling the Oxygen sensors. I would take the upper intake manifold off again. Just because you have the green rubber bolt seals ... doesn't mean they won't eventually leak ... but I would smear on some sensor-safe RTV before buying new ones. Use Vaseline on all the other large seals. Use Vaseline on all your air connections ... such as air-filter to throttle body, etc. Vaseline can help seal a lot of connections ...cure a lot of ills ... and it is intake-safe.

Do not overtightened the bolts!

After you get rid of P0171 and P0174, you can take on the other codes if they are still around.

[ditchmagnet]

Ok, I took it apart again and cleaned the seals and the bolts, and put it all back together. then I took a propane torch and opened the gas and moved it around the engine, the engine idled steady. I ended up replacing the bank 2 ho2s, and right now the only code coming up is the P0174. I really need to get this thing to pass emissions. If i take a small piece of cardboard and put holes in it, and place it on top of that circle wire mesh in the MAF, do you think that would work?

But what could be the main reason bank 2 is too lean? could a stuck egr valve cause this if its stuck open? or dirty ingectors on bank 2? it just doesnt seem like there is a vacuum leak right now.

[12Ounce]

Well, you made progress ... you're down to one code. I don't know how the cardboard on/at the MAF could help ... You still have a vacuum leak. Nothing exotic ... a vacuum leak! Don't get to hung up on it being only on bank#2 ... bank#2 may just be a little more sensitive than bank#1 ... the leak may be affecting both banks.

You may have to deal with the lower intake manifold. Before you start removing things, check out the IMRC actuator ... are the links in place? Is the PCV valve and hose in good shape? Did You put Vaseline on ALL the air/vacuum hoses and connectors? Put some around the body of the PCV valve. Take a small brush and put some around the gasket area of the lower intake manifold? ... the IMRC body shaft, etc, etc, ... made sure the hose that feeds the EVAP system is in place and not cracked.

[catvents]

Just an idea like that did you re-connect the big vaccum hose on the upper right rear manifold ( passenger side, firewall side back of the engine) ?

[Andrew1941]

I forgot that on my sister's van and it ran like crap when we started it up. You would probably notice if that wasn't on there....but check anyway. I was reading about the EGR system and its my understanding that if you do not get the recirc of the exhaust gases back to the engine, then you will not be able to pass emmissions test; however, where I live, there are no emmissions tests, so I have no idea how it is done. So if they do it at idle, the EGR system is not functioning anyway! If not, maybe the EGR valve is not opening. I would suspect you get a low flow EGR code of P0401 if this was the case, but ???? Just a thought....

[ditchmagnet]

Well, I took the extra mesh from my original MAF and put it on the new one (so there were 2 mesh circles). I unplugged the battery, and drove it waiting for the light ot come back on. The car now running rough, and obviously rich (a little liquid gas coming out of the exhaust) the CEL came back on and I took it to autozone. Only the p1151 is coming up now. I come home and took out the extra mesh, and now it again runs like a top. I had replaced the ho2s so i now that is working. There really does not appear to be a vacuum leak. I again took propane and released it around different areas of the engine, and it continued to idle smoothly.

As far as emmisions testing, they just have me turn off the engine, they connect the computer, and turn the key to the on possition. The system auto fails the van when it detects the codes. I just got a 30 day temporary plate, so I have bought some time and can still drive it leagaly, but am at a loss of what to do.

[12Ounce]

I would expect you now have a sensor issue.

Swap both primary and secondary sensors between bank#1 and bank#2, and see if the code switches banks or not.

[wiswind]

double check that BOTH IMRC shafts are connected and working.....nylon clips are known to break / fall off.
If 1 side is connected and the other side is not....then the motor will not be ballanced for air input between the front and rear banks.

You might also try a can of Berryman's B-12 Chemtool in the gasoline tank.....a dirty fuel injector can also cause a lean code(s).
The PCM is trying to ballance out the mixture with the injectors spraying different amounts under the same timing.

The newer method of emission testing is to just connect to the OBDII port and read the codes.
There is code that is set if the OBDII system has not been through all of the tests (which requires the vehicle to be run for some set amount of time / drive cycles).
So one cannot just clear the codes right before the test......and quick check it before the code comes back.
At least in Wisconsin.....they will fail you if the vehicle has not been run enough to clear that code (I think it is P1000).

[ditchmagnet]

So I still cannot get it to pass emissions. the only code I am getting though for a while now is the p0174. I have put on new port gaskets, and the big gasket in between the top and bottom of the intake plenum.

By the way, what is a IMRC shaft?

I had took it too the ford dealer, and he said it was a vacuum leak, and that i needed to replace the port gaskets, and the isolators bolts. he wanted over $500 for the job. I bought the gaskets, but not the bolts cause i have the new ones and they are about $7 a bolt. But should I still replace them?

The last thing I did was take the intake plenum apart and put high-temp RTV silicone around the green part on the isolator bolts, and a little on the threads, and put that together. I noticed that the little u-shaped vacuums rubber connector that goes to the intake, is hard and does not have a tight fit. i tried putting RTV on that connection as well, but that did not work. I put vasaline on all the other connections, but every time I reset the PCM codes, the light always comes on after about 5 mi. I really have no idea what to do, and I am about to put it up for sale. Please, any help would be greatly appreciated.

[skipster001]

have you cleaned the MAF with maf cleaner??

[12Ounce]

It's a long shot, but you may have air leakage around the gaskets/seals between the lower intake and the block. I don't know if it is possible, but you might be able to smear some heavy gear oil or Vaseline around this area ... to see if it helps. Otherwise ....

I would look everywhere else for an air leak before trying this.

[mundy5]

folks, this is an older thread

[12Ounce]

Originally Posted by mundy5

folks, this is an older thread

I know I'm ignorant of good cyber etiquette, or whatever ... but is there something wrong with using "an older thread"? Why?

[mundy5]

the last 2 posts were more suggestions to the OP who had this problem back in Nov. If he continued to have issues, he would have responded to the last 2 posts by you and by skipster.

based on the lack of response, I would suggest that either he solved the problem or it is unresolved and he has no intentions of solving it or some other situation.

like most of the threads here, after the solution is found, the OPs rarely post the actual solution which is unfortunate.