If it's jerking and spiking ICP while you're using cruise, I can't say I'm surprised. Cruise can be tough to get tuned in b/c it is adjusting the throttle more rapidly than you would be with your foot. Take it out of cruise and see if it continues doing it. If it's spiking like that with out moving the throttle, there's a problem in the HPO system most likely. If it's spiking like that from small movements in throttle, it could be fixed by slowing the ramp rate of ICP. Next time it does that. Take it out of cruise and stay steady on the accelerator and see how it reacts. FWIW, I've had a tune that would pulsate constantly in cruise control. Take it out of cruise and it was a perfect tune. LOL

 

Nate and Travis have valid points. You guys got it.

38-42% is low DC. There is more left.

The Cruise control is most likely the pressure issues. You may need a custom tweak to the tune. I know with Dual pumps, it get's tricky with IPR ramp and duty cycle.

215 is not terribly hot. Pulling a load like that, it's actually not bad at all. When it get's above 235, then it can be an issue. I believe stock calibrations start defueling above 235 or 240(you would need to consult your Tuner for that info, as that can be modified/changed).

Joey@TE

 

Hey look, it's this guy! I tried to send you an email today and it got sent back as failed to deliver. Edit: I think I got it to go through now. lol

 

Thanks Nate & Travis, like I said, I don't know if I have the guts to pull it across the country like this. A lot of guys do with 5th wheels, you see boats, trailers and cars. Pull thru campsites aren't bad, back ins you have to cut it off. At least I can tow that on four wheels. Guys that use tow dolley's have to get the car off then man handle the tow dolley out of the way. That would be a pain, all I have to do is fold up the hitch, its a stow away brand. There is always that uncertainty that 'if I pull in here, can I get out?' We have been running around town with the Geo for a couple days now its so nice not to have to park out in left field because it takes a football field to turn the old Mare around or try and squeeze into a parking place. My wife hates driving the truck, this gives me some free time because I can say, see you later, LOL

Thanks Joey for getting on, I couldn't help myself in sending you a link, LOL

 

I'm happy you sent the link! It's nice. I enjoy coming over here. Just not a lot of Forum time lately.

Travis, email found and responded.
Thank you,
Joey@TE

 

The figures I posted in #1 were in a tow tune. Today coming home I was in the Hot tune and got on it. DC% went up and topped out at 77% but ICP pressures were only at 2770 for a high, what I saw anyway. This is Gearhead's tunes, I will have Tony's back Friday but don't know when I can test them, probably in April.

I thought is was interesting that $99 dollar ebay camera worked so well. The pictures are after the sun set. The iphone took some good pictures also. Darn little Geo kept following me around! LOL

 

77% DC and only 2770psi with 160s? That pump isn't keeping up in the hot tune.. Lol.

 

Got that right! I thought the IPR D/C would max out somewhere in the 50's!?

 

I'm totally confused! Why would ICP go to 3200 at around 40% DC in tow tune and not exceed 2770 at 77% DC in Hot tune?

 

Longer PW on the injectors?

I think I would still wait until you get the other tunes in there before you call it insufficient HPO, but it certainly sounds like the HPOP is running out of steam up high in your hot tune.

 

I've never seen DC% go up like that, PW was about 1.7. Confusing also is that there was not any jerking in Hot tune.

Edit: I just thought (remembered) that I'm not comparing the tow to hot under the same conditions because I had it at 3K rpm in tow and 2,400 rpm in hot. I'm sure that would make a difference.

 

I don't think 600 rpm would make that kind of difference.

 

It will make some difference because the lower RPM will allow the PCM to call for longer pulse width and use more oil, at least that's how I understand it.

 

ICP was down and DC% was up in the hot tune because basically, the farther the injectors stroke (the more fuel they inject) the more oil that has to flow into the injector to continue pushing fuel out of it. The hot tune was running the injectors longer, therefore injecting more fuel and requiring more oil to get the extra fuel out. If the HPOP cannot supply enough volume to drive the injectors, there will be a pressure drop and you'll see the IPR DC% go up to try to make the HPOP build more pressure. Basically the IPR DC% just keeps going higher and higher, but ICP is lower than desired pressure and isn't increasing with the increase in DC%. That is when the HPOP is out of volume. It can't do what it is being asked to do.

 

Gotta run in the hot tune. That's the power tune. I was afraid you might run out of oil Glenn. Just took a year longer than I thought. May need to look into dual 15's. That's the most reliable bigger setup from what I've read. That or stay out of the hot tune I suppose.

Camera looks like it works real well!