Engine running weird / strange

[gotsomegetsome]

Hey,

I have a 1997 PSD with the ZF-5, 22x,xxx miles, ts-5 position chip, 6637 intake, diamond eye exhaust 4", new cps, 3x gauges boost, pyro, hpop.



I have owned the truck now for about a year, and I have noticed this "problem" has been occurring on and off.

When I start my truck, it will run like one of two scenarios.

First, I will have my chip set to 45+hp economy mode, more power than stock. A little boggey if I give it too much gas at around 1500rpm, Not as much power as I would expect.

Second, No matter if I have my chip set to 45+ or 140+ (I have stock injectors), the truck will run like a beast. Full power, not boggey at all, no smoke, running like it was brand spanking new breathing fire.

Here is what's weird. Sometimes it will be running like the second case, sometimes the first. Its never consistent. But, when it is not running like case two, the HPOP jumps a little bit up and down when at idle. Just a hair really. You can hear the engine rev up a hundred RPM or so at max. Almost unnoticeable.

Does anyone think this is an HPOP problem, sensor problem, something else I'm not thinking of? I've done some searching but so solid answers. I thought it would be my CPS, but I've replaced that recently.

[jesilvas]

First, are those canned TS tunes? 1500RPMs is right about the time the turbo lights, maybe a bit before. The nature of a V8 is to produce power at higher RPMs.
I'd pull the chip to test anything first. Then you'd have to monitor IPR and ICP values under WOT runs to see what they do.
Then reinstall the chip and do the tests again.

[gotsomegetsome]

I do have canned tunes. They weren't exactly custom for my truck or anything from TW. I thought all you do was give them your year and tranny and you're good.

Also, I've tested this without the chip and it happens too. The HPOP pressure varries a little bit.


Wouldn't I know that the IPR is giving false values if the orings are messed up? There is no leakage there. Just a thought.

Also, since I have no check engine light, shouldn't the ICP be okay?

Not trying to say you're wrong or anything, just trying to figure out what the heck is going on with my engine.
Thanks

[jesilvas]

Custom tunes are more than just year and trans option.

What ICP pressures are you seeing anyway?

I'm not sure I understand what you mean about the IPR. I'm saying that you need to watch the duty cycle and see if it is changing when the truck runs worse.
And no CEL doesn't always mean ICP is ok.

The other thing to check would be fuel pressure.

[gotsomegetsome]

In regards to the IPR, I thought that typical IPR failures are leaks at the orings sealing the IPR, where symptoms include poor idle, loss of power, and the engine dying.

As for ICP pressures, I do not have a means to check what the ICP is sending exactly in terms of voltage, but on my gauge it reads at idle approximately 300psi or so, and varies about 50 psi at worst for half a second when running poorly.

[jesilvas]

Well the IPR could be going bad too.
That is way too low for ICP readings. 500PSI is cranking minimum. So you have a HPO issue.

[gotsomegetsome]

ah sorry sorry, I read the gauge wrong. Its 600psi because each tick is 2 x 100