I have a '94 Ranger 4wd. It's got a 4.0 and 5 speed. I used to be able to run 87 octane fuel. The thing started pinging like crazy so we started using 93 octane. This worked for a little while, then when the ambient temperature started getting over 80 degrees, it started again.
The dealer couldn't find anything to cause this and they removed a "little adapter" that helped greatly. It turns out that all they did was pull my SPOUT connector! Now the thing pings only when we run anything except high octane. I know this is not supposed to happen...

By the way.. I've done the obvious.. checked for codes in the ECM, installed new fuel filter, plugs and wires...

This has the distributorless ignition.

ANY SUGGESTIONS????

 

What kind of a dealer mechanic would pull the spout and send you on your way? If you've checked your own codes,you're way better than they are! Now,without a distributor,you can't adjust base timing,but you can check for a mispositioned crank sensor if it's an external one.Besides that,I'd change the coolant temp. sensor to eliminate that possibility.Also, it's possible that FORD has came out with a different computer that contains a diffent running "strategy" to correct certain driver complaints that otherwise could not be solved by normal repairs or maintenence.Also check the EGR system.
Phillip

 

if you really believe that the fuel you were putting through your motor is what originally caused the pinging then try a bottle of injector cleaner and 91 octane gasoline then drin\ve a few tanks out of the truck and see if things change but try other suggestions first to avoid costly damages>

 

Phillip I own a 1993 Ranger 4.0 v6 with 62000 miles I live in Las Vegas and have the same problem with engine knock. Does not burn a drop of oil gets 22 to 24 mpg expressway driving. I thought of maybe cooler heat range plug. From what I found timing can't be changed. Retarded timing use to work. If you come up wiyh any answers plz email me at jrvegas(No Email Addresses In Posts!)

 

I (had) a Mazda B4000 (Same truck..) with a 4.0L 5/speed and It pinged very badly under full throttle acceleration.. Apparantly they didn't get the timing curve quite-right for real-world conditions with these engines, eh?

 

Phillip I own a 94 Mazda b4000 4x4 at around 60000 miles it started to knock under hard loads. I clean the butterfly ever three months and it seemed to help but came back. I went with better grades of gas it helped but came back. I now have 133000 miles. Two nights back I read an article on the net about cleaning the MAF sensor. I did't have a security tork bit to remove the sensor so I removed the whole unit form the filter box and sprayed carb cleaner through the screan at the sensor area. I did this in a half hour. I took it for a hard spin and no knocking. I'm back to regular gas and no knocking. Whod a thoght.

 

these kinds of things can also occur from carbon build up, from babying your truck, lots of short trips where it doesn't get up to temp, poor fuel. Usually a weekend of beating the snot out of it works good, it has in my experience. Otherwise there are shops that can de-carbon your engine. Some places will even shove a camera down there and you will be able to see the amount of carbon built up.

Matt

 

It is the MAF sensor that is dirty, and needs cleaned. BUT--- do it the right way, you will need I believe a #20 security torx bit I bought mine at the local parts store for about 4.00 bucks. Remove the 2 torx screws and carefully lift the sensor straight up there you will find 2 filaments like the ones inside of a light bulb. Be very careful do not touch them. While your at the parts store pick up some electronic cleaner that leaves no residue. Spray the elements from about 6 inches away from them, and let dry. Reinstall carefully and no more ping! PS: there is a small Oring around the base of the filaments make sure it is there when you reinstall.

 

Have you replaced your thermostat lately? If your engine runs cold, carbon will build up during the winter months. This can cause piston knocking or pinging.

They sell fuel additives that you add to a fresh tank of gas, that will clean out the deposits, but they cost about $5-$7.

Good luck!

 

I am having the same problem with my 94 4.0L. I'll try the MAF trick the next time I fill up with regular unleaded. Thanks for the tip.

 

Check out the thread "Valve knock under load".

"Nothing lasts forever except natural stone and old Ford trucks." (Willie Nelson)

 

I bought my 94 4.0L new and from day 1 I have used Amaco Silver (89 octane). I never really used regular 87 octane fuel much. I was going to replace the knock sensor but I found out there is no knock sensor so I replaced the thermostat and the antifreeze. Well, it started knocking on 89 octane and got progressively worse until I read the thread about cleaning the MAF sensor. so I went out to the garage to see if I could locate the MAF sensor. I removed the air filter and threw it to the floor and it was FILTHY. So I put in a new one and since I had been running 93 octane fuel to abate the knock I wouldn't know if the filter helped until I tanked up again. When it was empty, I filled up with 87 octane fuel and the knock came back but not nearly as bad as before. So I cleaned the MAF sensor and it didn't help a bit. I am now back where I started using 89 octane fuel and it runs pretty good. I have done a lot of in town driving with this truck which probably is a contributing factor and, somebody earlier suggested that the factory may not have gotten the advance curves right when they mapped them into the computer. I think that is absolutely right. Also, I don't understand why a dirty air filter would exhibit this tendency. When it filled up with dirt the MAF should have compensated for it and changed the fuel delivery accordingly.

 

 

I have a 1999 3.0L XL 2wd Ranger and I have the same problem with it. If someone has a advice please let me know.

Thanks

 

I have the feeling that many people don't use the proper type of spark plugs when they do a tune-up. When I did my tune-up a couple of weeks ago, I was AMAZED at how much smoother and quieter the engine ran after I fired it up. A quality set of the proper plugs and wires will do wonders for your truck.

Also, a new fuel filter when you do a tune-up helps a lot too.

I tried the MAF cleaning procedure on another Ford product I owned. I even used a Q-tip swab and alcohol to clean the black buildup off the sensors while I had it apart. I noticed no improvement in fuel economy after doing this and the engine still pinged like crazy.

The fuel additives may help to clean the carbon out some as well, but I think a proper tune-up is the key to an efficient and quiet engine. I can now run 87 octane with no problems.