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New Stage 1s and HPOP but truck feels weak

2238 Views 7 Replies 5 Participants Last post by  klhansen
Hey guys I need some help! In the past month I have replaced my stock injectors with a set of stage 1 injectors and I've put in a new HPOP. When I first replaced the injectors the truck ran smooth but it was extremely weak, after running a test on the HPOP we decided that the HPOP was weak so we replaced it. Now the truck is running stronger but it is still not up to the performance level it was running at with just the DP tuner and the stock injectors and old pump. I have been in contact with Jody and we are trying to get to the bottom of it but I figured it couldn't hurt to see if anyone else out there had experienced this.

It seems that the ICP pressure is still on the low side especially in the lower end of the RPM range. I have a video of a data log if anyone would like for me to email it to them to look over. Can't figure out how to upload it to the post.
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Jody adjusted my tunes to compensate for the new injectors, not that I'm not sure the problem isn't still in that area though.
I just had a thought (shocking, I know) - I bet your fuel pressure is low. It isn't a measured parameter, so the PCM wouldn't catch it. The Stage 1's are more dependent upon adequate fuel pressure. There are several places where the problem could be, from tank obstructions, pump problems, filter issues, and the most likely - fuel pressure regulator. You might pull your FPR off (on the side of the fuel filter assembly) and make sure it isn't gunked up. If you can, put a fuel pressure gauge on it.
I thought that at first but when me and my mechanic both took some time to think about issue We both felt i would be having a bigger drop off in the performance as the performance level of the tunes in increased, but the really strange thing is that my stock and 60 econo tunes seem to be almost identical at least as far as how the truck feels performance wise, both tunes feel weak on the low end of the throttle. However if I switch to the 100hp performance tunes the truck is off the charts power and performance wise.

Is there something I missing in my thoughts about this, I'm still very new to the upgrade market and I'm nit very skilled on the inner workings of tuning and fuel delivery.
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