Last week my new pop tester arrived so I could finally get on with reconditioning my injectors. I've had mine done by a reputable firm before and it did make a bit of a difference then, but there seems to be a bigger improvement in performance this time. Last time the engine did become a bit quieter, but this time it is much quieter and it seems to have picked up a bit of power as it is holding a higher gear, for longer, than before (this might also be why it seems quieter...).
A couple of lessons learnt:
- Don't buy a cheap pop tester! I had to buy a 2nd one from BGS that actually works.
- Your work area needs to be clean, clean, clean. A few times I had the right shim but couldn't get the crack pressure right, and each time it turned out to be tiny dirt (e.g. lint from the cloth I was working on) getting into the injector.
- Use a decent digital caliper to measure the shims. And measure the springs too - 1 of mine was 0.5mm longer than the others. This doesn't sounds like much, but 0.05mm = almost a 100psi difference, so 0.5mm is huge!
I ordered genuine Denso nozzles and the full set of genuine Toyota shims, springs, spacers, etc from Amayama. Alternatively if you don't mind the truck being off the road for a few weeks, you could take your injectors out and inspect them first before ordering everything. I think that my tips weren't actually too bad, and I think they would still be perfectly serviceable with a good clean - just don't use anything metal to clean them with, only wood, rags, etc so that you don't mark them in any way (the surfaces are highly polished).
These spacers even come coated in a waxy plastic layer to prevent them getting marked at all.
Injectors with old nozzles:
The new tips come in small containers filled with oil - this oil needs to be rinsed off/out of the tip with clean diesel or you will struggle to get the crack pressure right.
A shiny new tip.
