2004 GJ 4.7...any reason why I shouldn't use these injectors??? I Have been chasing a misfire code and removed injectors to clean and noticed that 2 were cracked and 1 was a different injector. 7 were 2 hole injectors with a red stripe and 1 was a 4 hole injector with a green stripe!!!! I found Bosch 3rd Gen 4 hole upgrade injectors online for $151.95 from Precision Auto Injectors. I know 1 stock injector at my local autoparts store is about $45...so $150 for 8 sounds pretty good to me. Any thoughts would be appreciated!!!!!

I bought a set of the same injectors from the same company for my 4.0 and they're working perfectly. 2 of my original Seimens injectors were cracked as well. Just remember they are remans; cleaned, flow tested, coil tested, and spray pattern tested. Flow rate really doesn't matter much because the PCM controls mixture by regulating "on-time." Smaller fuel droplets created by the 4-holers make the idle smoother and the off-idle response quicker. I found the tires would slip coming off a stop when going over the white painted stop lines until I learned to softpedal it a little.

Thanks Dave...glad to hear some positive feedback...what would make fuel injectors crack?? Seems pretty odd.

On 4.0s, it's heat from the exhaust. It's probably just cheap plastic anyway. There's just a thin layer over the magnet coils.

Where can I buy the 12 hole injectors and 62mm tb that your talking about?

Tests have been done that show there is very little gain to be had in going more than 4 hole. There's a good vid on YouTube that shows them side by side. 1 hole to 4 hole is a big difference. 4 hole to 8 or 12? A very slight difference. I would not waste my money or time looking for 12 hole.

I know, I know, more is always better, right? (That's why people do dumb things like using 00 welding cable for their starter. It does nothing useful, but it's bragging rights.)

No, it's not. Sometimes it's worse. Sometimes it's slightly better but not enough to make it worth the effort and cost. This is one of those times.

As for the 62mm, if you are not also doing some exhaust work you are probably wasting your time and money.

Here's the stock vs. 4 hole video, from the company mentioned above.




Here's 4 vs. 12. You can see there's not much to get excited about.