my 1988 f150 with 5.0 has started to ping quite abit. any ideas?

 

more info is needed.

mileage, what have you done to fix it, was it sudden, etc.

 

I had a similar problem w/my 91 (302). After hours upon hours of troubleshooting I actually found a bad plug wire. Changed the wires making sure of good connection, Problem Solved.

There is a ton of possibilites but I'd look here first. Good Luck

 

Mine does the same thing, but only under a load at lower rpms. These engines have a knock sensor and I wonder why it still continue to detonate?

 

Same problem on mine . Up hills and lugging the engine a bit its pretty bad. most of the time i manually shift out of overdrive just to get the Rpms up

 

Umm, check the routing on #7 and #8 plug wires. If they're side by side for more than about 2 inches, bad, VERY BAD. It'll ping, misfire, cough, snort, wheeze, and make all sorts of sounds you wouldn't think an internal combustion engine could make and stay in one piece.

I had BRAND SPANKIN NEW Motorcraft wires on mine, and still got the infamous 7/8 cross-fire. Nothing showed up in the dark as leaky, but until I re-routed them to keep 5 and 6 between 7/8 as long as possible, my truck ran like poop, and got LOUSY mileage. Through the troubleshooting, I installed a set of the Bosch Platinum II's. Best I can say about that is DON'T. Stick with the Motorcraft plugs. Run the Bosch plugs in an air-cooled VW with conventional breaker points ignition if you want, but stay away from Ford's TFI with 'em. Ford's TFI will eat Bosch plugs for lunch.

The Bosch plugs are what brought me in here tonight as a matter of fact. I only found the messages about them in here AFTER I'd installed them. Thought I'd go ahead and give 'em a go and see how they worked out. They didn't, period. #8 electrode ceramic was coming apart when I pulled it tonite. #5 had worked itself loose, so no wonder the lousy fuel mileage and sputtering. Lousy mileage to me on my truck is 16 mpg. I say that, because it's long legged (3.08 dif with M5OD tranny in front of it) and I've seen it do 22 mpg highway, dependably if I use the cruise at 70-75 mph. Put the Motorcrafts back in tonite with a little copper anti-sieze on the threads to help seal, and this is the smoothest this truck has run in 4 years, despite donating large sums to the Ford charities at the dealerships. They don't really do any work, at least none that fixes any problems, so I can only figure the money is for unlisted charities.

CLUNK (me getting off my soap bo)

Check the wires, dizzy cap, rotor, plugs. It ain't so bad pulling the plugs on the 5.0L in the truck. I find #7 and #8 easiest to get out from under the truck so the brake master isn't in the way trying to reach them from the side. At least with the shorty headers they are a piece of cake to get to from underneath. The others still require the rib-breaking techniques. I use an old steel milk crate to stand on due to being vertically challenged to reach all of the plugs from the sides.

I like the MSD dizzy cap/rotor set. It's all copper, and that will hold up better in Alabama's humid conditions than the standard Motorcraft cap which has aluminum electrodes. Something about jumping a spark through wet air between a brass electrode and an aluminum one that causes some pretty nasty build-up and a little pre-detonation (ping) at times. Besides that, the red cap looks good under there too, and it has a screw-on retainer that will keep the wires tight at the cap too. As far as the wires and plugs are concerned, though, I learned my lesson there. Motorcraft, and ONLY Motorcraft will be used there for the rest of the years I own this truck. Stay away from the Bosch spark plug gimmicks. It's a German plug, put it in a German car. Gonna post a photo of #8 plug which looks remarkably like a photo I've seen in here.

 

[QUOTE=brrossi]my 1988 f150 with 5.0 has started to ping quite abit.
i would look at the egr first, they will become clogged. remove the egr and with a vacuum gauge pump it up and look to see if the egr opens. if it does not move i would soak it with something like pb blaster. clean the area around the plunger. apply vacuum and it should become free and open. the ping should go away with the egr opening. use a new gasket.

 

Thanks for all of your help. I think it may be the EGR. However I don't think cleaning it will revive it. I may have to look at purchacing a new one. Last I checked they were about $50 to $ 80.

 

Umm, pinging is usually a sign of lean misfire or pre-detonation. Timing too far advanced (goofy TFI module) or intake leaks (see my gallery) can cause the pinging, as well as an EGR that's sticking OPEN. OPENING the EGR at the wrong time (acceleration, idle, WOT) is a BAD thing. The EGR is only used when at crusing speed on the highway. At idle, WOT, and under some acceleration conditions, the EEC will CLOSE the EGR to prevent lean mix ping. The EGR uses exhaust gas to deliberately displace fuel/air mix when power is not needed, and efficiency is the game of the moment. If you want to rule out the EGR, it won't hurt a bit to cap it off to test your theory. Take a soup can and flatten it, punch a couple holes for the bolt holes, and put it between the EGR and the intake. I used the graphite gasket from the EGR to mark the bolt pattern. Leave the EGR intact, otherwise, count on a 33 code. Make sure you use a STEEL can. If you use aluminum, the exhaust gas may burn through.

If you wanna check for intake leaks, get a propane torch, and go around the intake system with it unlit, and point the gas at everything you can reach. If the engine suddenly idles up and smooths out, you have a leak. The plenum on the 5.0 is notorious for leaking, and trust me, it WILL make the truck ping and run like poo.

 

EGR will reduce pinging by cooling the maximum combustion temperature. A stuck open EGR valve will make the engine run terrible, but won't cause pinging.

 

Yes, timing was the problem with my 92 F150 5.0L
Its gotta be where the sticker says it should...

 

you never said if you messed or checked the timing.

10 degrees btdc with the spout off is where it should be.

 

Why do these 5.0s still ping even with the knock sensor? Is the sensor not working?

 

There's only so much retard (I've read 4°) that the computer is programmed to make when knock is sensed. It's set up to pull a set amount when knock is sensed, then it will add it back in after a set time. I don't believe the computer ever scales the spark table values based on long term knock like it does with the fuel tables using O2 sensor feedback.

 

Thanks, I'll have to check the EGR, but it's not throwing any codes. It's probably a lot of carbon build up on the pistons with 167k on them.