Alan,

It' weird. When driving it has what I guess is normal pressure. I'll need to jot down some notes while the cruise is on this evening and convert them. It's when it comes down to idle, it comes down to zero then jumps up to the 6,xxx number. It's like it loses the sensor or over/under-ranges. Looks like the computer has lost count of it's device so it displays the max value. I see this alot with the PLC's and Analog IO stuff we deal with at work.

I doubt that's the problem though. I need it to get real cold before I see it on a cold startup.

What's agood range fo the ICP pressure and sensor voltage. On the rive to work this morning the ICP voltage seemed to be jumping between 1.8 and 2.2 volts. Seemed odd. Almost like the HPOP was constantly spiking pressure. I have a new ICP I'll try and stick in there this weekend to see if Inotice any change.

Also, anybody know anything about the "cylinder rotation change" parameters on the Predator? Mine stayed at zero while driving and then a few cylinders registered a few percent at idle. Anybody know anything about this?


Thanks

ICP - I'll have to look at the voltage charts when i get home but 400-600psi at idle a hard accelection can spike it above 3200psi. It will vary some depending on demand.

My MAP reads withing 0.1psi of ambient while at idle and then ambient + boost while driving.

On the rotation change if you see > 0 while driving there are bad problems. These are the sensors used to do a CCT. At idle with truck at NOT and in drive with parking brake applied none should read > 3 -5 % and the lower the better.

the cylinder rotational change is measured in percentages. It is a cylinder contribution test. it shows a the rotational change in velocity of each cylinder real time to show if you have a week cylinder. what percents were you getting?

OK, I'll verify it today on the drive home, etc... But about 5 cyl's are at 0% at idle and 3 are between 0-3%. I don't recall seeing any that were higher.

I thought there was a way to physically turn off an injector and see what "contribution" it was giving to the engine?

Not without building a cutout box. But I do have the instructions if you need them.

Guys,

It got cold last night. I cranked it up this morning, it wasn't plugged in last night, and romped as usual. I shut it off and plugged in the Predator and restarted and viewed the data. All looked OK. Once it started running smooth 4 codes showed up. One was the wastegate one again. Not sure of the number. I'll pull the codes in the AM and post them.....

Hopefully we're headed in the right direction here.

Here's the codes that showed up again

P0606
P0605
P1211
P1690
P1249

I've been working too much to pull the chip and drive it to check codes again. It says the 1249 code is the wastegate control solenoid. What exactly does this do? Could this be my low power problem. I thought the wastegate was pressure actuated. Am I overboosting causing this?

While driving, with the cruise set at 70mph, I made the following readings with the Predator:

Outside air temp was about 65*
Manifold inlet temp is 130C*
Baro press 102.2kPa
Manifold absolute pressure is 107kPa
Manifold gauge pressure is 19kPa
Injector pulse width was 2.2mS average, single bank
Injector control pressure was 10.5mPa, voltage was between 1.86-2.5vdc
70mph
2000rpms
fuel pump duty cycle 100%

There is a problem there with the boost numbers. Baro looks about right but MAP should be BARO + Gauge Pressure. Since Gauge pressure is a calculated reading of MAP - BARO (107 - 102.2 = 4.8) ???? Need to get some unchipped numbers.

BTW": I cranked the service truck this AM after sitting for a week and I could barley get her in the stall she was such a dog. Now to get the VC's off this afternoon.

I'll get those numbers without the chip. I'll double check these numbers today on the cruise home. I did manage to get the manifold gauge number up to 100kPA. It climbed pretty quick to that going up the bridge.

As Alan pointed out something is wrong with the numbers. Since I am better with PSI I went ahead and converted them so my pea brain could work with numbers I am familiar with. (#s rounded)
Baro=14.82 psi (below sea level eh?)
Map=15.52 psi This diff should indicate about .7psi boost at gauge
Gauge=2.75psi ???

If these numbers were taken via a scan I'm not sure how it botched the math by about what equates to 2 psi. Either way, even the 2.75 number may be a bit low running at 2k at 70mph.
Might also want to try removing the wastegate tube and plugging it by placing it on one of the inlet clamp bolts and retry the same test to see if the loss is at the wastegate/diaphram or connection. IIRC the wastegate should default to the closed position.

As far as I know, the PCM uses those numbers as well as others while calculating fuel strategy.

Tenn, Thanks for the tip on unplugging the wastegate tube. I'll take readings this evening with/without it in place.

And, yeah. I'm definitely below sea level down here in New Orleans.

Any idea on the P1249 wastegate code? Is the wastegate controlled by the PCMas well or just the boost line going to it?

Thanks. I'll post up late tonight with some more data.

The PCM Commands the waistgate solenoid to pressurize the Accuator to "Open" the waistgate. That is where the Green and Red lines come in to play.

On the service truck: 5 of the 8 injectors where "Loose" to the touch. All of the rocker arm bolts needed at least 1/4 turn to bring to spec one was almost a full turn out. Copper washers appear worn and will be replace as well as all the orings even though they look OK. The UVC harness even though it Ohm'ed OK from the IDM connector appeared severly burnt on the connector inside the cover. Injectors are on the way to be tested and will pick them up tomorrow.

OK, so follow the red line and I'll find the actuator.

Good (I guess) to hear that there was something wrong with the service truck. I want to say all I did to mine while under there was shake the rocker arms around. Only one cylinder seemed loose an I figured it was due to the lifters being on the heel of the cam (both valves closed)..... Guess I'll pull them and retorque them.

Keep me posted on the testing of the injctors.

Yes one end of the redline is the Solenoid (Black plastic on intake Y) and the other is the accuator (gold cannister)

So no boost reference signal from the red line and it will default closed 10-4??

Also, those loose injectors and rocker arms (not to mention poor harnesses that tested OK) have given me a lot to think about. Kwikk just posted about his loose rocker arms recently... I am about hunted out and sick of working overtime. (Xmas Bills :-down).
I think I will definately need to take a look under my VCs in the real near future. Not because I have a problem but because I don't want to have one.