Another DII Brain-Teaser!

[Brian McVickers]

Hi,
Ok, earlier this week we all discussed the misfire in Cylinder #6 of my 2001 DII with 102,000 miles on it.

Everyone did great on that one, lots of help and great advice resulting in new wires and new plugs installed.

So lets try another one!! :wings:

I disconnected the battery
I replaced the wires and plugs
Put everything back together and the engine runs great
No check engine light anymore

Fast forward four key sequences and about 25 miles --- The Check Engine light is now back on. :mixed-smiley-030: The engine sounds fine.

The ODB Codes and what I can find and their translations are as follows:
P1171 = Oxygen sensor system, System too lean Bank A & Bank B
P1174 = Lambda Control Adaption Fault Bank 2, Last Occurence - maximum signal, Control Fuel Air.

First, I'm not too sure what these codes mean and what needs to be done to correct the problem.

Second, there could be three contributing factors to keep in mind.
1- I just replaced the old spark plugs with new OEM plugs
2- I just replace the old wires with Magnacor brand which are well proven
3- I had to physically lay on top of the engine in order to replace the wires, I laid a folded blanket on top of the engine and a large piece of cardboard on to p of that to lay on.

Thoughts, Ideas?

Thanks
Brian

 

[yubert]

On the top of engine is the air intake hose with a MAF sensor, you might want to check the electrical connector to make sure it wasn't dislodged or there are any cracks in the intake hose. A bad MAF can cause the engine to run too rich or too lean.

You might also want to check your oxygen sensors and the connections.

 

[R_Lefebvre]

Yeah, you could be getting some un-metered air due to a leak in your intake system. Could be a hose on the intake pipe, or could be a leak in the intake manifold from the stress of you laying on it? I think 1174 means that the computer tried to adjust the A/F ratio by opening up the injectors, but reached some preset limit of how far it's allowed to adjust, like 10%.

 

[FourByLand]

I was dealing with the same thing and I replaced my Y-pipe and all is better... I replaced my MAF, all o2 sensors, plugs, wires, blah blah blah... it was my cats.

Good luck chasing.

I'll be replacing idler pulley's on Monday.

 

[Brian McVickers]

I think I found it.
On the passenger side of the engine there are two tubes that go into the throttle body, at least I think its the Throttle body. One of them is a larger diameter = 1/4 inch, rubber tube that fits onto a plastic nipple that threads into the engine. Well it cracked and broke clean off right at the threads!
It took a couple of minutes but I was able to get the broken off threaded portion of plastic out of the engine and now I'm looking for a replacement.

Brian

 

[R_Lefebvre]

Yep, that would do it. Hope that's it.

 

[Brian McVickers]

I searched at all of the autozon, napa, checker, pep type auto stores and nobody has this little plastic piece. The RAVE program officially calls this piece the "Breather Hose Adapter" = the breather hose from the Inlet Plenum/Manifold.

The catch is that the adapter is about 1/4 inch in diameter but has a smaller hole inside to regulate flow.

I replace it with a brass threaded/nipple of the same size that I found at Home Depot. I installed it, cleared the codes and will drive around a bit today. I drove it about 5 miles after the fix yesterday and stopped and started about five times to allow for five key sequences and the light has stayed off.

I'll stop by the dealer on Monday to see if they have this proper piece with the regulating hole. If they do not have it my mechanic neighbor suggested filling the brass adapter with solder and then drilling a hole in the middle of the solder that is the same size as the regulating hole in the OEM plastic unit.

Thanks again for the help!

Brian

 

[Martyn]

If they do not have it my mechanic neighbor suggested filling the brass adapter with solder and then drilling a hole in the middle of the solder that is the same size as the regulating hole in the OEM plastic unit.

Thanks again for the help!

Brian

Brian

I like mechanics who think like this. So many people are such linear thinkers, where if you can't get the OEM part you're sunk.

 

[muskyman]

gone

 

[Brian McVickers]

Any of you guys see a any long term risk with using the brass adapter filled with solder? Interaction between the brass fitting an the aluminum manifold?
Possibility of the solder breaking off?

Thanks
Brian

 

[R_Lefebvre]

Both of those are a risk. I'm not sure which way the cathodic reaction will go, but you'll surely have one. And a slug of tin going through your engine would be VERY bad. I don't know what the likelyhood is, but just the possiblility makes me wary. You have to be careful about what you put in the intake system.

 

[Brian McVickers]

I agree, I just purchased the OEM plastic fitting from the dealer.
It is made of Polyamide #6, a special heat tolerable plastic from the sounds of it.

The brass fitting is fine for a day or two when the parts shop was closed or to get you out of a jam, It's running fine even without the special regulator hole so as a field repair I don't even think the solder trick would be necessary.

New part will go on tonight.

Thanks
Brian