2000 Ranger XLT SC, 5-sp
I have had a spark knock in my engine for over 2 years. At first the problem was minor, but over time it has gotten worse. It is less of a problem when it's cold outside and worse on hot days. I have brought it to the attention of my dealer no less than 6 times. First, they discounted the problem. Then they recognized the problem but said there was nothing they could do. They consistently claimed that there was no service bulletins or other remedies from Ford. Then in April of this year, I did find a service bulletin that seemed to be relative. I asked them about it and was told to bring it in. They replaced the coil and the processor. This seemed to help a bit, but over time the spark knock got worse again. I've been running high octane gas which limits the problem, but it doesn't go away completely. Last week, the CHECK ENGINE light came on. I stopped at an Autozone after work and had them read the codes. It showed a P0133 (O2 sensor slow response) and P1131 (sensor indicates lean mixture). Yesterday, I took it into the dealership to have them look at it. Their response was: (1) they can't find/fix spark knock problem (2) they wanted to replace oxygen sensors at a cost of $300+ (3) The "slow sensor response" and "lean mixture" codes had nothing to due with the spark knock. I delined to have them replace the oxygen sensors if it wasn't going to fix my spark knock. Additionally, they charged me $60 to verify the same check engine light codes that I initially provided. So, the bottom line is that they've fixed nothing. Needless to say, I'm not happy. My truck doesn't run very well, my gas mileage has dropped off considerably, and it lacks power, especially on hills. I need to get this resolved and have no confidence that my dealer is interested in addressing the problem. Also, this problem occurred well within the original warranty and has not been resolved. My dealer now tells me that I need to pay for any remedy on their part. I've been more than accommodating with the dealer and probably should have raised a flag sooner. I need help. What can I do?

 

To start with, I would replace the sensors. I wouldn't let Ford do it though, I would do it myself. It's not that difficult and when they start to throw codes for slow response they are usually worn out. When they indicate lean it could be because of the slow response or it could be that you are indeed running lean. Running lean will tend to cause more pinging than running normally as it is easier to ignite a lean mix and it will raise the comb temps making it even easier to ignite prematurely. So, in a way, this does have something to do with your problem. Running lean may be a result of a fuel filter getting old. Has that been changed? Too bad you can't get them to cover the work. I know how that goes. I blew a motor (not in my ford) 15 miles over warrenty and the co. wouldn't touch it.

 

i dont know if this applies to a 2000 model, but on my truck and other models i've looked at there is an 'octane shorting bar' it looks just like the old "spout" connectors ford used to use for timing. anyway if you pull off that "octane shorting bar" it will retard the timing by 3 degrees which should help with your spark knock. as far as you lean condition.. check the easy stuff first, look for vacuum leaks, especially around the pcv valve.

 

I forgot to include the fact that my truck only has 25K miles. Is it normal for the oxygen sensors to go bad this soon?

 

Hi jrfields;
Welcome to the FTE Family! Well...along w/ everybody elses opinion, i'll add mine too: The way your truck has been running, i'd say the cat must have a build-up of soot, creating back pressure, causing loss of power, from insufficent exhaust flow!
You may also need a decarbonizing! Carbon effects spark detonation, which creates spark knock/pinging!
Let us all know what actually happens in the end!
________________________________
The Brain Is Always On The Move
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My Beastie:
90 Ranger 2.3L EFI 2wd Mazda < with many new parts!

 

Normally I'd have to say no, they should live longer than that unless there is something else going on that killed it. It can happen though. I think Ford is using some questionable sensors lately. I have already changed several in windstars with less than 10k miles.

I have also noticed that when they say "slow" it is usually the sensor, when they say "stuck rich" or "stuck lean" it is because of something else causing them to stick on their limit.

 

I would replace the sensers and clean the MAF. Don't worry about the cats since you have been running lean.

 

jrfields, welcome to FTE!

At 25K miles and less than three years of ownership (I think), isn't the truck still under bumper-to bumper warranty?

The P1131 code refers to your passenger's side front (or "upstream") 02 sensor and is set when the 02 sensor tries to correct for an overrich condition.

The P0133 code refers to the SAME 02 sensor and can be caused by the following:

- Contaminated HO2S sensor.
- Exhaust leaks.
- Shorted /open wiring.
- Improper fueling.
- MAF sensor.
- Deteriorating HO2S sensor.
- Inlet air leaks.

So based on the above, you should probably start by checking for vacuum and/or exhaust leaks, then check the connections to the O2 sensor itself for corrosion, shorts, etc., then you ought to clean your MAF sensor. If none of that works to get rid of the codes, then replace the 02 sensor itself (stepman is right, replacing the 02 sensor is not that hard to do, and you can get them at any reputable parts store).

Hope this helps...good luck!

 

I would just like to clear something up here. The O2 sensor DOES NOT try to clear up the condition should it be rich or lean. The O2 mearly detects what is coming down the pipe. It sends this information to the computer and it's the computer that trys to correct the condition.

 

This should provide some more info:

 

Where did you get that? the bottom part is worded wrong. Other than that though I could agree with it.

 

He cut it from the Ford manual I believe.

 

What, are you guys a tag team? I just don't like the way that is worded. I have known ford manuals to be wrong before. I was just saying that the O2 does not control the fuel. The computer controls the fuel according to the INFO that it receives from the O2.

 

stepman,

FWIW I think your point is a good one ...it is indeed the PCM's role to correct an overrich condition. The 02 sensor is just that ...a sensor ...merely providing data back to the computer so it can do it's job.

The wording you don't like I believe comes from the fact that the 02 sensors are constantly being monitored (tested) by the PCM...

 

LOL, I knew what you meant and I agree. Your turn Joe.