Hi Guys,
Having trouble with the old 1994 F-150
it has the inline six with 192K on it.

The trouble is, in Drive, the idle lopes, like it wants to die, but never does.

I have since replaced the Plugs, Wires, Cap, Rotor and Idle Control Valve, air filter and breather filter, all OEM Motorcraft Parts, and it still is rough. The only KOER code I was able to get was 225, the knock sensor code. Which I am not really sure would make the truck run rough.....

Any help is greatly appreciated.

Thanks
Wes

 

Knock sensor would definitely cause a problem, one went out on my dads buick and it wouldn't even crank, same thing on a friends yoda

 

Try cleaning the MAF sensor? The MAF was dirty in my wifes` ride and same problem. How is it when you hit the accelerator from a rough idle? Does it go right away , or hesitate? Did you try a higher octane?
Hope this helps.

Sty

 

Hi Wes

Also if eng. is fuel injected...how are the injectors? Also pressure.

Hows the fuel filter? Also...with that many miles...if not already done..you might consider doing a compression ck. on each cylinder. Just thoughts i had.

Good luck...OT

 

The knock sensors signal to the ECU changes when detonation (aka pinging) is occurring resulting in timing retard. If it is malfunctioning and sending a signal that the ECU recognizes as that condition when it in fact does not exist, timing retard would still be applied. This is just a possibility, but since you have a trouble code for the knock sensor, I would eliminate that first before going on in your diagnostic. Old fuel filter is bad news for fuel injection as well, if it's been a long time or not at all replace it now.

 

Ford throttle bodies are bad about getting gunk built up in em, least it is on mine, starts idling rough or surging. Clean the throttle body really good and its fine. Might try that

 

Hi Gang, I am still fighting with this thing.

You can read the top post, and since, I have replaced the Knock Sensor, Fuel Filter and the O2 Sensor. Still runs rough and gets 11 MPG. It BARELY passed Emissions testing in Houston.

Old Timer, how does one check the injectors?

I cleaned the throttle body out, and it still runs rough.

It now has 199K on it, I am going to replace the fuel filter again, I bought this truck used, so who knows what crap was in the tank when I picked it up.

I was also thinking all those tune up parts that I bougt, I might have something in there that was defective....cracked plug, damaged wire etc. I might just tune it up again. I work this truck hard, and it drives great. Just idles rough.

ANy ??

 

Give it two Auto-RX treatments to clean things up and make sure you have good oil flow and ring movement. Then dump some Neutra in the gas. If it does not run smooth then you know you have a mechanical or sensor problem.

I treated all my cars with Auto-RX and the one that surprised me was the Pontiac Sunfire driven by a 21 year old since he was 16. It was beaten, run out of oil, then beaten again. After treating it the thing hits on all four cylinders.

The Neutra is cheap, the Auto-RX is expensive. You can use the Neutra in the oil the same as Auto-RX.

 

Greencrew,
where do you get these two things? I have used Seafoam in the gas and Lucas Engine oil treatment, both which seem to have no effect.

I am really looking towards the EGR valve...

 

Most engine oil treatments will get rid of the sludge, but won't touch the carbon or the varnish. Both Auto-RX and Neutra will slowly disolve both. I have read good comments on Seafoam, but don't know much about it and have not used it.

Auto-RX is only availabe on the internet at www.auto-rx.com. Some Amsoil dealers are providing it as a cleaner to be used before changing to synthetic oil.

Neutra is a Schaeffers product which has been around a while, but you have to find a dealer. I just call this outdoor power equipment dealer in Texarkana. 800-737-1747 They ship it out in about four days. I order it by the gallon because it is only $13 for a gallon, or $3.50 for a 12 oz bottle. I did have to get one bottle so I could pour it into the gass tank. You will need a #1 plastic bottle or it will soften the plastic.

Normal application for Neutra is 1/2 oz to one gallons, but I have heard some run as much as 2 oz to one gallon for faster results. It also works faster if you pull out the spark plug and pour 3 ozs right in the cylinder and let sit for three days.

Thanks for asking.

 

I'd run lube control and fuel power, will work better than any of the products above.

 

I just added Fuel Power to my gas earlier today after I filled up. Good choice for cleaning the fuel injectors.

Lube Control

 

Funny thing, I STILL have not fixed this issue yet. I believe the issue at hand here are the injectors. If I idle the truck in park, The exhaust coming out smells RICH, (slightly gassy and sweet, but not coolant sweet).

However, at this point, i am having transmission/driveshaft issues. Need to replace the U-Joints. GRRR!!!!