94 f150 5.0
ok this is ticking me off
this is what i have done
plugs
wires
cap
rotor
timing at 10 btdc spout out
removed egr ckd diafram and the valve does seal it held and it moves up and down when
when i gas the motor.
cleaned the maf hot wire
this is what i think i still need to do remove egr run air
in the egr hole in the plentom to see if it is cloged
i all so have filled up with union 76 fuel super and it seams better
but insted of pinging at 2800 to 3200 rpms it pings at 4000 rpms
i dont run truck at thease rpms just after i do somthing to
try and fix this problem.
and i did have fuel injection serviced but they did a cra*&^%$
job they ran the cleaner threw the power brake boster vac line
and put a bottle of cleaner in the tank.
could this be a carbon problem? miles 99000
the truck has on hard or soft codes 2 codes did pop up when
the motor was running #538 and 632 i cked the codes on a sight
that i found here and they tell me that the goose test was done wrong. the guy that ran the test dident give a spific place or
scencer to ck thats why i was suspect of what he told me
i found a place the uses a motor vac for the injection i think
that it might be a good idea to have it redone.
help i am running out of things to try.
thanks
marc

 

I recently had the motor-vac done on my 92 and it made a big difference. Also I would switch plugs over to Motorcraft or Autolite if you haven't already. My truck was pinging really bad under a load but was ok around town. Had it checked and found out it was running lean. No codes and nothing not working right. Changed gasket between plenum and intake manifold and pinging went away.

 

well i did the motor vac to day am glad i had it done
but it still pings.
as far as the plentom gasket did your motor serge like it had a vacum leak?
thanks
marc

 

I do think I could feel some surging under hard excelleration.

 

This probably is not your problem but I had pinging with my '93 302 and it finally failed at 68,000 miles and I found an article regarding 1987-95 PCV System Modifications On Ford 5.OL Engines. I'll paraphrase what I found. JASPER found a pattern develop in the #8 cylinder of the Ford 5.OL, V-8 gas engine. This pattern was the failure at the #8 piston or the #8 rod or rod bearing. What was discovered at JASPER was the #8 piston would exhibit excessive heat on the underside at the piston. JASPER narrowed the problem
down to the PCV system. These 1987-1995 applications supply the vacuum source to the PCV valve by a 3/8" threaded hole in the rear of the intake runner. This is the runner for the #8 cylinder. The #8 cylinder supplies most of the vacuum for the ventilation system and any oil mist that enters the PCV system will be drawn into the #8 cylinder. This PCV valve cover has a splash battle located by the PCV valve hole. The baffle has a drain hole that must be kept clean. If it becomes blocked, the baffle will collect and hold oil. The PCV valve will then pull the collected oil from the baffle and feed it to the #8 cylinder, eventually causing excessive temperature and pressure buildup. This causes excessive stress on the piston. rod and rod bearing which may manifest itself in the symptom of pinging. Mine operated like this until it failed. It has since been repaired and runs better than it ever did. Ford routed the PCV system to the center of the plenum and not to a single runner since '94-'95. They say that this allows for a more even
distribution of the vacuum source to all 8 cylinders. It is important to insure that the drain hole in the valve cover is kept free from any blockage. You can re-route the PCV valve vacuum supply hose yourself. Mine has ran so good since repair that I haven't bothered with it. But if it starts pinging excessively again -- I think I'll perform the modification.

 

my 95 F150 started pinging going up hill with the a/c on i started running plus 89 octane gas and it went away runs like a champ now

 

Try adding a bottle of Techron Fuel System cleaner (not Techron Fuel injector cleaner) to about 1/2 tank of fuel. Do this a couple of times. Supposedly it cleans not only the injectors, but helps burn off carbon deposits on top of the pistons and inside the combustion chamber.


Worked well for me.

 

Bump

 

Bump

 

bump

 

You can re-route the PCV
>valve vacuum supply hose yourself. Mine has ran so good
>since repair that I haven't bothered with it. But if it
>starts pinging excessively again -- I think I'll perform
>the modification.

I did this on my truck and it made a world of difference. I rerouted the PCV hose to the vacuum tree at the center of the manifold and rerouted the brake booster vacuum hose to the PCV old location on the back end of the intake manifold.

 

had teh same problem wiht my 95 F-150. I gave it a drink of water to clear all the caron out and it went away for a little while and eventually came back. I have just recently installed a Pro-M 77Mass Air meter with conical filter and the truck has not pinged since i installed it and i have noticed a lot more pickup from 55mph and up.

-keith