What is the life span of the injectors on a 97 5.8. As yall knowm I have been burning up the posts trying to fix my pinging problem.

I have 175k on the odo, and I really believe the injectors are original. Could bad /old / dirty / injectors cause my problems. Spark Knock is a lean condition, if they are not flowing what they should be, could that be the problem. The truck runs great/smooth but as the clatter.

 

i got well over 300k on mine 300 in line 6-mine runs great!

 

It only takes 1 partially blocked injector to really mess up a motor since the EFI system fires them in batches, it will cause that cylinder to run lean and nothing will cure it. You may be able to isolate it by reading the plugs is you find one that is white while the others are tan or brown.

 

Conaski is correct... one bad injector and you have much aggrevation. If you can isolate the pinging sound using either a mechanic's stethoscope (harbor freight, $5, Harbor Freight Tools - Quality Tools at the Lowest Prices) or a hardwood dowel you touch to the engine in various places and put the SIDE of the dowel to your ear (don't put your ear over the end - easy way to rip your ear off should something bad happen), and isolate which cylinder is pinging. Once you figure out which one is pinging, you depressurize the fuel system, swap injectors with one that is obviously not pinging, then repeat.

If the ping moved, then the issue is the injector. If it remained in the same place, it's something else.

If you're cheap like me and want to acquire a set of matched replacement junkyard injectors, build yourself an injector testing station. All you need is a junkyard fuel rail, an EFI fuel pump off any car or truck that's in the fuel line rather than in the tank, several mayo jars, a battery charger and a simple "555 timer" circuit you can get off the web that drive's a mosfet - which powers and pulses the injectors.

Instead of gasoline you can use mineral spirits if you want, and simply "inject" your "fuel" into the mayo jar. Measure the volume after a carefully timed minute or two, then repeat for each injector. Depending on the volume differences, you can then select from your collection of junk injectors a matched set that flow about the same.

If all eight injectors flow a little less than they should, or a little more than they should, the EEC will automatically compensate. The issue is when one or two flow to much or two little where you ahve problems, because they're batch fired as Conaski stated above and the o2 sensor(s) cannot differentiate between individual injectors.

That's another reason why many folks convert to mass air - some mass air systems do not fire the injectors as a batch, but instead sequentially - one at a time.

I happen to like EDIS mass air systems of all that Ford offers, but that's a lot of rewiring for the average guy who doesn't want a lot of hassles.