I just changed my plugs wires and rotor on my 1990 5.0L and I suddenly have a ping at heavy throttle. I used bosch platinum+2 plugs that are factory pre-gaped. The twin electrodes are not supposed to be changed. I have used these plugs on other engines with good results. I did notice they seem a bit shorter then the motorcraft plugs I took out. Timing seems fine by ear, I haven't got out the light yet. But it was fine when the old rusted and pitted cap rotor and plugs were on there. Any idea or should I just switch to some nice autolite plugs.

 

Stock Motorcraft Nic plates copper cores. & check timing advance. Bosch Plat 2's cost me 2 pistons. Not a truck plug!!!

 

Thanks Ill pull the plugs. I just heard from someone that they are doing the same thing in their 03 focus.

 

Changed the plugs to stock motorcraft coppers and the ping lessened. Still getting some at acceleration. Timing is set at 10 btdc per factory rec. I am getting a code 33 no egr opening. I checked the egr sensor and it seemed to have a high resistance (@500 ohms open), tried a new one and same reading. It also occured to me that the truck has run cold ever since I got it. It runs about halfway between cold and normal in all situations (traffic, high speed etc.) I know the fan clutch is gone but the temp sensor and thermostat are new. I was thinking maybe it isnt getting to proper operating temp to open the egr?

 

You'd get an ECT out of range code if it wasn't reaching op. temp. EGR function isn't temp related.

Either your EGR regulator has failed, or EGR valve diaphragm is ruptured, or EGR Vac hose is leaking or disconnected or valve is clogged shut & can't open.

 

Sorry to here that! They'll be sorry too!

 

That would defiantly be a cause for the ping right. So its time to get after it with a vacuum gauge.

 

When will I learn not to trust o/p's code definitions. #33 for truck's is failure to close properly! So still EGR regulator bad, or clogged EGR not allowing closure. & that could definitely cause ping! You will be over lean from the get go.

At idle, there should be no vac flow to the EGR valve from the regulator. If if there is vac, EGR regulator is bad.

Is that code active or continuous or both? Wouldn't surprise me if that sensor error code was in continuous & locked out as an active.

 

Im getting it as a continuous and with engine running.

 

At idle, there should be no vac flow to the EGR valve from the regulator. If if there is vac, EGR regulator is bad. The other option is the EGR valve in fact is not seating closed.