I've never had a problem with my k&n either but when i put my flow master on the light came on bcause of low backpressure...you should change your exaust also because your letting in more air so you need to get rid of more air with a less restrictive exhaust...

 

I just got back from picking up my truck. It was the (HOS2) heat oxygen sensor this time. I am suprised they didn't try to blame this on the exhaust Mod. I wander how many sensor will go bad next week.

BigRed2, go back to the same dealer and let them know about the 2000 stock cobra with the K&N mentioned in this thread. Also let them know that other Ford owners have had their MAFS sensor covered under warranty even though we have added a K&N. They have to prove that it is the K&N 1st before they deny you warranty coverage.

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99 XLT 4.6 midnight blue reg-cab, Airaid K&N, dual exhaust

 

BigRed2-
Here are two of the codes from your pickup:

P0133- O2 Sensor Circuit Slow Response (Bank 1-Sensor 1)

P0131- O2 Sensor Circuit Low Voltage (Bank 1-Sensor 1)

P1131- Manufacturer Specific (Since second digit is not a zero). I would assume this is related to the first two; that is the O2 sensor on bank 1. Sounds as though your dealer is jacking you around. There's someone on this board with the Autotap software who could clarify what this code is.

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'98 F150 XL Regular Cab, LWB, 4.2L V6, 5 Spd, 3.55 LS, Rhino Lining, factory heavy duty suspension, 3" Gibson Swept Side Cat Back, K&N filter, Oxford White minus the two tone garbage. BIG TIME FoMoCo p/u fan, not some fair weather hammerhead.

 

Ford Man thanks for the help.

The P0131 says check air cleaner intake for restrictions after it don't know if this is valid but that's what the work order says.

What are the sensors on the intake. I know the MAF is in the filter assembly but whats the one down stream in the flex hose.


What are the purposes of these two sensors?

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99' F-150 XLT SC 4X4 ORP LS 4.6L K&N Air Filter Air Box Mod (3" intake from fender & silencer removed), Superchip, A.R.E. Cover, Duraliner bed liner, Rapidflow 3" single CatBack exhaust.

 

BigRed2,
BirdMan has done some extensive resurch on the Mass air sensor. For a complete understanding of this sensor see his site at www.flash.net/~rfm2/

It helped me out.

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99 XLT 4.6 midnight blue reg-cab, Airaid K&N, dual exhaust

 

CM, I tried the link and got page not found.
How did your day go with the dealer?

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99' F-150 XLT SC 4X4 ORP LS 4.6L K&N Air Filter Air Box Mod (3" intake from fender & silencer removed), Superchip, A.R.E. Cover, Duraliner bed liner, Rapidflow 3" single CatBack exhaust.

 

BigRed2-
From what your codes are indicating, your engine is running too lean (at least the O2 sensor is giving the computer a signal indicating this). The voltage signal from your O2 sensor is 0.6 to 1.1 volts if the engine is running rich, and 0.4 volts, or less, if the engine is running lean. The MAF sensor uses a heated wire to measure intake air. It will send a signal, based on the amount/rate at which it is cooled, to the vehicle's onboard computer. The signal will increase commensurate with an increase in intake air and your spark advance and mixture are adjusted accordingly. If I were you, I would put a paper element in my pickup and go to another dealer as if nothing happened. That's pure BS on the part your current dealer, trying to worm out under the guise of a K&N causing the problem. The sensor may be bad, but it was probably defective from the get go. It's still possible, however, that the O2 sensor is sending a false signal.

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'98 F150 XL Regular Cab, LWB, 4.2L V6, 5 Spd, 3.55 LS, Rhino Lining, factory heavy duty suspension, 3" Gibson Swept Side Cat Back, K&N filter, Oxford White minus the two tone garbage. BIG TIME FoMoCo p/u fan, not some fair weather hammerhead.

 

Ford Man where is the O2 sensor located, as you can tell I am at a loss here with out a service manual. Thanks for all the advise I have an appointment tomorrow at 7:30AM. I am totaly back to stock on the intake except for the silencer in the elbow.




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99' F-150 XLT SC 4X4 ORP LS 4.6L K&N Air Filter Air Box Mod (3" intake from fender & silencer removed), Superchip, A.R.E. Cover, Duraliner bed liner, Rapidflow 3" single CatBack exhaust.

 

Looks like the O2 sensor tripped the service light. They tested the sensor and it reported to be OK. They said if it trips again they will just replace the O2 sensor. I plan on leaving the intake stock and keeping the chip out for a while, maybee until spring.

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99' F-150 XLT SC 4X4 ORP LS 4.6L K&N Air Filter Air Box Mod (3" intake from fender & silencer removed), Superchip, A.R.E. Cover, Duraliner bed liner, Rapidflow 3" single CatBack exhaust.

 

Here's a link from Gale Banks Engineering's web site. As one of the most respected producers of aftermarket power equipment for pickups, they have some very strong thoughts about dealers and warranties. I would encourage EVERYONE to check this out.
http://www.getpower.com/GBwarranty.html

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'98 F150 XL Regular Cab, LWB, 4.2L V6, 5 Spd, 3.55 LS, Rhino Lining, factory heavy duty suspension, 3" Gibson Swept Side Cat Back, K&N filter, Oxford White minus the two tone garbage. BIG TIME FoMoCo p/u fan, not some fair weather hammerhead.

 

Well I didn't get far and the service light came back on. Went back to the dealer and they need to have it for more exstensive diagnostics, it will go back on Monday. I spoke to the tech and he said just replacing the sensor might not fix the problem becasue apparently the sensor isn't bad? Well then why is the sensor reporting a problem and Ford Man as you mentioned why only one sensor?

The other dealer went for the air filter I guess becasue that Ford code pointed to a restrictive air cleaner? That's as far as they got and my truck was out of there.

I think I will pursue this bogus treatment with the local Ford mfg Rep. The dealer where I purchased my truck service department sucks, they botched the lambar support repair 4 times. I should have known not to go back.

Thanks to all for the help I will keep you posted.




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99' F-150 XLT SC 4X4 ORP LS 4.6L K&N Air Filter Air Box Mod (3" intake from fender & silencer removed), Superchip, A.R.E. Cover, Duraliner bed liner, Rapidflow 3" single CatBack exhaust.

 

For the MAF people the www.flash.net/~rfm2/massair.htm link was down due to server issue. Try it again.

BigRed and all, these error codes sound just like Crusty had also. The dealer service dept is a bunch of boneheads. Rarely will a low mileage vehicle have these kinds of problems without a major malfunction. If they tested the O2 and found it ok then they should be checking for a bad injector or incorrect fuel supply. The EEC will use O2 sensor input to adjust A/F ratio up to about 25% of the range. If it can't then compensate then the MIL "check engine" light comes on. The reason you don't see it right away is that until the motor is up to operating temperature it runs in open-loop, which basically uses all the sensors. Then once the motor is up to temp the O2 sensors will take the upper hand.

Is your Superchip still installed through all this? Have you taken it out, cleared codes and rerun the truck for a while?

There can be many reasons you have a lean condition so hang in there and keep an open ear to the service guys. Don't try and tell them just try to redirect them to the fuel system. Heck, you could even have a bad computer. They will try to resolve it as quick as they can to get you out the door, they get paid by throughput not success. Put your foot down and tell them if they give you the truck back and the check engine light comes on later, you will be talking to the regional rep and you want some compensation. You getting loaner ride or their f-ed up Courtesy shuttle?

I myself have found very few dealer service departments that are no less crooked than the sales guys. You have to play their game until they respect your rights as a customer, otherwise screw-em.

birdman

 

BirdMan, I took the chip out first thing and I am glad I did these guys are amazing. Do you know what the other sensor located in the black flex tube behind the air flter. What role does it play in the scheme of things.

Thanks for the help.

 

BigRed2-
The codes NEVER indicated the air breather, they were showing error codes from the Bank 1 Number 1 O2 sensor. It would be hard to diagnose your pickup from here, but I think I can safely say, "IT'S NOT BECAUSE OF YOUR K&N!" The MAF sensor has its own error codes indicating too little air flow, bad circuit, etc., that would indicate the problem is elsewhere. It could very well be a bad computer and they'll have to replace/reflash it. Read the link to Gale Banks Engineering, I think the dealer service department just didn't want to "mess" with you and figured it would be in THEIR best interests to send you along. The Banks link talks about something similar, where a dealer denied an individual warranty service on his POWER DOOR LOCKS because he had added EXHAUST MODS!! You can't trust any of 'em any further than you can throw 'em.

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'98 F150 XL Regular Cab, LWB, 4.2L V6, 5 Spd, 3.55 LS, Rhino Lining, factory heavy duty suspension, 3" Gibson Swept Side Cat Back, K&N filter, Oxford White minus the two tone garbage. BIG TIME FoMoCo p/u fan, not some fair weather hammerhead.

 

BigRed2-
You have four O2 sensors total; Bank 1 (passenger side) before and after the cat, and Bank 2 (driver's side) before and after the cat. Theoretically, I can understand the first dealer's logic, if the MAF sensor thought it was receiving an obstructed air flow, it would cause the mixture to run lean. However, why weren't any of the codes brought up indicating poor air flow to the MAF? Was the MAF frequency tested? Why was only ONE O2 sensor indicating a lean mixture? I suspect that particular O2 sensor may have too much resistance, either in it, or the circuit. The only way to know for sure would be to check that sensor and circuit with a multimeter and compare it with the other sensors and circuits or others known to be in working order. Sounds like your new dealer (I assume you've taken the vehicle to another) is a little more on the ball than the first.

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'98 F150 XL Regular Cab, LWB, 4.2L V6, 5 Spd, 3.55 LS, Rhino Lining, factory heavy duty suspension, 3" Gibson Swept Side Cat Back, K&N filter, Oxford White minus the two tone garbage. BIG TIME FoMoCo p/u fan, not some fair weather hammerhead.