My truck has been a dog as of late....I took an AE reading, but not really sure what to think of it. Any help deciphering would be appreciated, and if I need to create more data...........I can.

As for the truck:

No tune.
New IPR (500 miles)
New ICP (cheapo, 1000 miles)
New Injectors (Rosewood) stock (5000 miles)
New Compressor wheel.......anti surge
50 cent mod
EBPV delete with the 1cent mod?
199,000 miles

SYMPTOMS:
Lack of power both on start and high RPMs
High EGT
poor fuel economy
I can only get about 14psi on boost gauge, no higher
CEL light flickers once just prior to shift point, and also at begining of climb.....light does not stay on.

CODES:
P1209
P1211

I was suspecting it was the HPOP getting weak, but the more I read, the less I think that. My HPOP is a replacement, used with who knows how many rounds on it. I have had it for two years and I has worked fine. But maybe these AE readings will tell a different story.

I am building a boost leak tool today to check that route......

The graph:
Green - ICP Duty Cycle
Blue - ICP
Orange - Engine RPM
Red - Manifold Pressure

Thanks for taking a look.

Mike In MN

 

Before you get too much further into this, put a fuel pressure gauge in it and see what it reads at wide open throttle, under load. Low fuel pressure can wreak havoc on injection control pressure readings, causing IPR duty cycle to be elevated outside of normal range, thus setting a P1211 DTC.

 

Sounds good, I will purchase a fuel gauge for in the cab...even if the the following does not solve my problem......

My truck is doggin.......I discovered I have a frozen right rear brake caliper....should have went there first, this is a common problem..this is probably my fifth caliper that has done this in 7 years......ugh

 

Brake is fixed, some of the doggyness is gone, but not completely.....will install a fuel pressure gauge sometime within the week or so...
I removed the FPR housing and noted a deformed o ring on the poppet....thought maybe this was causing a fuel leak in return line, thus making my fuel pressure low....no such luck.
checked for boost leaks because it was free....no leaks.
Seems like my truck may be running a bit warm too.....I suppose I should look at the ECT and the EOT readings as well....
Good grief, there is a lot going on here.....lol

 

You either have an internal leak, your HPOP went South, or your tune magically re-wrote itself. The ICP is very low, and I see a Stinky spike in there.

I'm leaning toward internal leak. Pull the HPOP lines loose from the heads, and grab an air gun and a rag. Blow pressure into the HPOP fitting on each head, wrapping the rag around the connection. We refer to this as the Cody test. Gurgling and losing air? You have a new focus point. Holds air? HPOP is more suspect, but more info needed first.

 

Fuel pressure should still be checked first.

 

I don't disagree with the fuel pressure thought. The Cody test is free and can be done immediately. The fuel pressure gauge needs to be ordered, shipped, and installed. Either way, a fuel pressure gauge is important with the age of the truck.

 

Why does anyone need to order and install a permanent fuel pressure gauge to run a simple test? All the parts to check fuel pressure can be obtained from most any hydraulics shop. They can probably even make a hose that has a -4 male ORB fitting on one end.

 

I appreciate both responses.....I will be checking both....nothing but time here between sleeping and working.
I like the free test, speaks my language, but I also agree having a wiz-bang fuel pressure gauge is ok too....
Why do I have to order one? Because of where I live......The auto parts stores here are still stocking velocity stacks and edelbrock intakes for small block chevys......and apart from our rip off napa joint, I don't know of any hydraulic shops, and if there is one, UPS is probably still a little faster.
Thanks for the advice, again, I appreciate it more than you know. I will chime in when I get this wrapped up.

mike

 

Well FP is one thing we can't check with a scanner and I really like the idea of being able to check FP any time I want without rigging up a gauge, especially while travelling. Think about it, you are on the road and suddenly having power issues. A quick glance at the gauge can tell you right away if you need to go in that direction or if it is something else. I wouldn't be without mine.

 

I agree that a fuel pressure gauge, permanently installed, is a good idea. But for the purpose of diagnosing a specific problem, a 0-100 psi gauge, a length of hose that will reach outside the engine compartment and an adapter are all that is needed. You don't really even need the ORB adapter; there are 1/8" NPT ports, one in each head. They're just not a lot of fun to get a fitting in.

 

or...5ft of 5/16-30r9 fuel line, 0-100 psi liq filled gauge and a few hose clamps, and secure the hose to the fuel drain pipe

 

Here is where I am at after a stall out the other day.....now I have a NO START situation.
Truck began to lose power, no response at throttle, began to shake a little without knocking, then just shut down while in traffic....luckily I was moving enough to coast off the road and the girlfriend had her AAA card for a tow to my brothers yard, as I was 50 miles from home.......

Codes before trying anything...................
1280
1209
1211
1212

Running stock, no tuner.......
Disconnected the ICP..............NO START
Replaced ICP with known good spare.............NO START
Replaced IPR with known good spare...........NO START
Replaced FPR poppet sleeve because it looked like it needed it..............NO START
Checked FUEL filter (new two weeks ago)..............Looks like new, not black
Degas bottle has nothing but green liquid in it, looks good.
Oil level good(changed 500 miles ago with correct oil)
Oil in LPR is where it should be

CLEARED CODES and tried cranking.............NO START
NEW CODE.......1212 ICP LOWER THAN DESIRED
BUZZ test............PASS
CODY TEST..........PASS
KOEO test............shows EBP code, but that has been there for a couple of years, deleted that a long time ago

Here are the cranking results for two days.......I am thinking my HPOP did give away....

 

Include ICP voltage in a cranking log. If there is a low ICP condition while cranking, the PCM will ignore the sensor after a certain amount of time and it will use *and report* an inferred pressure based on other known engine sensor parameters.

 

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