Severe Gas Ping on '94 4.0L

[hammer58]

My 94 4.0L has a severe gas ping on acceleration. When I disconnect the spout connector, which retards the base timing, it really helps alot. Can anyone tell me if this will hurt my fuel milage and why do I have to disconnect the spout connector. Does this decrease the power?

 

[fox]

ya thats not good, have you ever overheated it, DON'T lie. i used to. if you did you need to check compression in all of you cylinders. they should be around 200 psi, get a manuel to chech for shure. if you have overhaeted it they you will most likely need new heads. the casting is of very poor desing, the are very well known fro cracking in sutch a way that they are unfixable. so you need to check your compression. just taking that plug out is not an answer, thats just delaying the enevidable. any Q's just ask.

 

[MSTNGGUY88]

Your timing is just to high man. Bump it down a few degrees and try it. This isn't any big deal. You won't see a mileage difference or feel a severe power difference. Ask a local mechanic if you think i'm crazy but try it. Anytime the timing is too high on a vehicle pre-detenation occurs and every motor seems to be different on the amount of timing they can run.

 

[hammer58]

How do you adjust the timing on a Distributor-less ingnition?

p.s. it has never been overheated

 

[srvblues00]

I had really bad pinging in my 94 Sport in all 5 gears. I then cleaned the MAF sensor and the problem was instantly solved. I would still recomment doing the above suggestions, but I think you should add this to the list! My truck still pings slightly on the interstate once it has heated up pretty good (middle of heat range on guage) when I give it a lot of gas. I'm thinking about taking off the upper and lower intakes, cleaning them, gasket matching, and replacing the gaskets. Good luck and keep us posted on the progress.

 

[MSTNGGUY88]

I knew that your motor has never been overheated. I never thought that in the first place. I've never even heard of that before causing a ping and i've been building motors for awhile for personal rides. I will check into how you can adjust that on your own but I think that it might can only be done by a certified mechanic though because it has a crank trigger. I've never changed it because my buddy works for Ford and he hooks it up to the computer at his work and changes it that way. Sorry I couldn't help anymore.

 

[hammer58]

I never heard of overheating causing a ping either. That was a suggestion from Fox. I found a post regarding re-torquing the intake manifold bolts. I'll try that and also cleaning the MAF sensor. Thanks for your help guys and I'll keep you posted.

 

[Lemondrop]

My 94 Ranger splash I killed in a crash did the same thing . The MAF (Mass air-flow Sensor) was DIRTY . The little filaments inside the sensor had gobs of dirt and nasties stuck to them . Without the MAF working correctly , then engine dosent know you are doing anything other than reving the engine at idle . It will only send a small amount of fuel (signal) to the injectors as it dosent think you need more . This will cause a lean fuel mixture which will cause the PING your getting .
Remove the MAF (Im sure it's on the airfilter box ) You will need a special TORX bit ( a security version) the 2 screws that hold the MAF on are security torx bits that you can get a removal tool for at just about any auto parts store . Get some Oxygen sensor safe carb cleaner and blast the 2 filaments off (after removing the MAF from the airbox) . Once they are clean and dry , install the MAF and hook up the wires . Also be sure to re-torque the intake lower bolts ( where the intake attaches to the heads at ) . These are known to loosen and cause a air leak inside the engine , which can result in a ping .
Best bet is the MAF being dirty . If yours suddenly started doing this be sure to check your airfilter and or replace it . Also check for leaks between the MAF sensor housing and airfilter housing , as if it draws dirt in it's bad for the sensor and your engine .