I have a 1994 ford ranger with 90,000 miles 2.3l 4 cylinder with a 5 speed manual and everything is stock but a k&n filter. I got the truck 2 years ago and when ever I am on the highway and put it under load it starts pining and knocking and making noises that it should not be doing. I have tried my best to fix this problem and can not figure it out so I am bringing it to the forms in hopes that some one can help me out.

What I have done is
1.change all 8 spark plugs to bosh platum plugs
2.did 2 motorvacs (is supposed to clean the fuel rail injectors and all carbon out of cylinders)
3.ran 2 cups of water into a vacuum port to get rid of carbon
4.used 10 – 20 bottles of chevron fuel system cleaner
5.ran a 3m total fuel system cleaner kit ( does upper intake and throtel plate)
6.changed the fuel filter
7.changed the PCV valve
8.remover the octane spout plug that retards the timing 3 degrees
9.took out the MAF and inspected the little wires to make sure there was not crap or carbon on them

now this is everything I can think of to do I am out of ideas and I need some help. I pretty sure it is not carbon because I think I have ran enough cleaners to get any carbon that might be in there out.
the only thing I could think of is the O2 sensor but it is not cheep from ford so if anyone know how to test it let me know and I will. I need the pin out because it is a 4 wire heated sensor and I do not know what wires do what.

PLEASE SOME ONE HELP ME I DO NOT THINK I CAN TAKE THE PINING AND MORE IT IS DRIVING ME CRAZY

 

Will it ping with premium grade gas?

 

Welcome to FTE
You mentioned that you changed to bosch plugs. That may be the problem. Some Ranger owners have had problems with that brand of sparkplug. You may want to go back to OEM plugs (Ford) and see if that helps with the problem.

 

the pining was there befor the bosch plug and that is y i changed to them. it also pings with 94 gas

 

Have you tested the fuel pressure, low pressure can make it run lean.

 

yea i had 42psi i think

 

After all that fuel system cleaner, your O2 sensor is probably shot.

Some of that stuff really scews up O2's. It causes the exhuast to run hottor because of the really thin, highly explosive petroleum distilates in most of them. That gets the o2 sensor too hot and it never reads right again after that point. It may not set a code, because it will still see the sensor switching and responding, but won't give a accurate air/fuel measurement.

IMO, replace your O2 sensor.

 

i thought that when your O2 sensor failed it would cause a rich mixture not a lean one. am i right or could it go bouth ways. i do not know much about them is there any way to test it?

 

It generates a voltage when hot. I think it is around 1 volt. Lean makes it go one way, rich the other. Do a search for a more accurate description.

 

To check the O2 sensor:
White wire= These are for the heating element. There should be 2-6 ohms resistance between the tw0 white wires.

Black & Grey wires= O2 sensor output. You should measure about 1 volt between the grey & black wires when the sensor is HOT. You need to run the truck to get the sensor hot for a couple of minutes while doing this test.
Dave

 

May be your lower intake manifold bolts. Common problem. They work loose and exhibit symptoms like you're seeing. These may need to be re-torqued.

 

i rebuilt my 96 engine due to loss of oil pressure, after rebuilding it, i found that a bolt somewhere within the engine is loose and makes a rattling sound. it only makes that noise when reving the engine between 2k-3k rpms. is close to your problem?

 

I had the same issues with a 91. Finally found the SPOUT connector, sometimes called a octane plug, and pulled it off. This retards the timing and no more pinging. I had tried everything also. Gas mileage decreased about 5 miles per gallon but its worth it if I don't have to listen to all that pinging and knocking. The computer is ultimately just too aggressive in adjusting the timing to maximize fuel economy.

 

If you pull the spout you lose ALL timing advance.