Floored it Wedneday and got serious pinging. Thought maybe bad gas so Thursday I step up to 89 oct. No ping when flooring. Then today the ping is back! '98 4.6 with 54k miles. Truck is not running hot when it pings. MAF sensor or ???

 

MAF or a lot of other things. But Yah, i'd clean it. Couldn't hurt. Run a couple of tanks of premium and injector cleaner.

 

change fuel filter and flush injectors check the EGR

 

Man this is not good. I thought by buying a very clean low mile truck I would be in the clear and now I have $166 spark plug change issues, possible plug puking down the road, and now intermittent pinging issues.

 

the 4.6 isnt bad about puking plugs... u probably just bought a truck that was hardly driven so likely there is alot ofbad gas in the tank. id drain the fuel or run it empty then put fresh gas in or mix some acetone in about 3oz for 10 gallons will fix the fuel. but i recomend premixing it first instead of pouring it straight in. and dont get any on the paint!. but it sounds like u just have a fuel system problem.

 

Thanks Everyone!
I will follow the steps outlined here. It probably is not a major issue.

I just have been getting frustrated working on vehicles as I'm getting ready to sell an old Chevy truck and I had a lot of detailing ect to get done on it as well as trying to work in minor stuff on the new F-150.

 

https://www.f150online.com/forums/sh...d.php?t=243541

It worked for me....

In 1.5 yrs I've also replaced:
- plugs
- wires
- pcv valve
- fuel filter
- Exhaust Manifolds (both and all hardware)
- Ex Man to EGR tube
- Oxygen Sensors (both fronts)
- Sway bar links (both)
- Ft Shocks
- Ft tcase switch
- Cleaned: throttle body/egp ports, IAC, MAF.

The truck actually runs great at 103k.
I did all the improvements before cleaning the MAF. It pinged like crazy until just a simple spray of electrical parts cleaner.

 

Hi Jim,
I did put in a new air filter about a week ago. There was a lot of jostling to get the new one in right so it would clamp shut. Hopefully this did not damage the MAF. I plan to do the cleaning like you did and maybe take it out and examine.

 

Is the 4.6 a V8, and if so, is the firing order such that it fires 7, then 8?

They're side by side, and I read somewhere if the plug cables are too close together, you can get pre-ignition by induction, I guess 8 fires early whilst #7 is firing. If while you were doing other things, you've caused the plug wires to get closer together, you could try to separate them - usually if you slide them back and forth in the retainer things, you can adjust how the wires sit.

 

haha no there is enough sheilding on the wires.. that it wont contact over... the only thing it may cause is EMI. and if the wire is going to ark anywhere it would be to the head or the block... a ground not a positive.

 

damn ud have to be pretty rough with it to damage the MAF changing the filter out

 

It's not arcing, but induction....I came across it quite by accident, try doing a google search...such high voltages, it's not impossible...

 

I think that can happen. The example I heard was #5 & #6 as they occur in the firing order in sequence.

 

im not saying its not possible... im just saying its unlikely unless there is a faulty wire... even with me hving 40ohm wires and 42kv coil packs ive never run into this problem. and im runnin the hottest coil packs for the fords.

 

I removed my air filter and looked inside the housing and there the sucker was--The Notorious MAF! So I bought the electrical parts cleaner and sprayed it good. Did not even have to remove it. There was no pinging today but as it is an intermitten problem can't say its solved yet.

Also bought a fuel filter and dumped in some Chevron injector cleaner. I floored it a few times to check for ping and noticed a puff of smoke, could that be from the injector cleaner in the fuel? What is the injector cleaner? It smelled like some kerosine base concoction.

May not have caused pre-detonation but I have had problems with spark plug wires arcing before.

Thank you for all your input(s)!

This is a great site!