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New PMD still Problems...

For purpose of trouble shooting snubber not really necessary in a permanent install yes snubber would be handy to dampen pulsations, but we are just doing a field test to determine if we are having a significant loss of fuel pressure so I would not get all excited about a snubber this go around.
 
You're getting more exited than me about it,i was just mentioning it.

BTW on both my 6.5 trucks the gauge needles where fluttering so bad one could,nt read the press most of the time if ones life depended on it.
 
When I had my fuel pump/vacuum gauge hooked up to the drain line it didnt bounce much at all. It held steady while idling and it would drop with fuel demand. When my OPS died intermittently I would see it go to vacuum. The valve itself is like a snubber if its not fully open.
 
Well got the cable in today and WOW why did i not order this sooner? But as for my problem it was not running any codes. and when it finely sputtered the only thing i could notice was the ip at idle it would flucaute from 17.44-18.23-20.93mm3. Does that mean anything?
 
Did the replacement fix your problem ???

Those fuel reading with a basically cold engine ??? if so the cold advance is coming into play, once it warms up what does the rate go to?

Bad FSDs/PMDs don't always give you a code, they can code but not always.

This is why it takes a little finesse to trouble shoot the issue, we rule out the free to check and low $$$ things 1st before replacing drivers or IPs, vs a GM tech that generally resorts to trouble shooting by part swapping, because they really don't know any better, and cash strapped dealerships can generate a lot of cash troubleshooting this way.

Ergo we have a saying around these parts; "Friends do not let friends, take their 6.5s to (Fiends/Stealerships/Dealership techs)"
 
Those fuel rates are way too high at idle, needs to be about 8-9mm3. take a screenshot at a normal warm idle, and then copy it and paste it up here. Screenshot is in the dashboard view, then you go to file and open screenshot. Got to see it all to understand where the issue might be coming from. And if things are different, also post up a screenshot of when its running rough.
 
buddy said:
Those fuel rates are way too high at idle, needs to be about 8-9mm3. take a screenshot at a normal warm idle, and then copy it and paste it up here. Screenshot is in the dashboard view, then you go to file and open screenshot. Got to see it all to understand where the issue might be coming from. And if things are different, also post up a screenshot of when its running rough.
Click to expand...

The version i have doesnt let me take screen shots. In file all it has is setting and exit.
 
thats too bad, well, please get the desired idle, engine speed, actual IP timing, desired injection timing, measured injection timing, TDCO offset, and fuel rate at a normal warm idle, BARO, intake air temp, fuel calibration, injection pulse width, cam reference missed, crank reference missed.
 
Alright results are IN! Here are the readings at normal running temp.
1. Desired idle- 638 RPM
2. Engine Speed-600-619-638
3. Actual IP Timing-26.84-27.37 DEG
4. Desired Injection Timing-5 DEG
5. Measured Injection Timing-4.8-4.9 DEG
6. TDCO Offset- 0.35 DEG
7. Fuel Rate(at normal warm idle)- 18.12-18.44 (NO SPUTTER)
8. BARO- 13.61 PSI
9. Intake Air Temp- 166.2F
10. Fuel Calibration- 130COUNTS
11. Injection Pulse Width- 2.02-2.06
12. Cam Reference Missed- 0 COUNTS
13. Crank Reference Missed-0 COUNTS
14. ENGINE TEMP AFTER IDLE 15 MIN (with no airlfow) 204.4

Im pretty sure one of my problems is my IP IS TURNED UP WAY TO HIGH! I can put it in drive and small black puffs of smoke will come out.
 
You have no way of controlling IP output, it is done electronically.

Holy crap, your idle temp is way too high. Is that what the temp gauge shows too? If that is correct you have a cooling problem. Like is there water in it?

Fuel rate is way too high too, doesnt make sense. pull the glove box out and pull PCM out, open up the hatch on the back and see if the EPROM is aftermarket. Ive seen something similar before with a bad aftermarket program. And at a minimum get the 4 letter code off of the chip.

Is that TDCO a positive or a negative value? If positive that is not good.

Pulse width is too long, should be less than 2.0.

And why is intake air 166 at idle? Is that sensor wrong too, is it drawing air from under hood?

So you have a PCM (or sensors), PMD, or IP issue.
 
buddy said:
You have no way of controlling IP output, it is done electronically.

Holy crap, your idle temp is way too high. Is that what the temp gauge shows too? If that is correct you have a cooling problem. Like is there water in it?

Fuel rate is way too high too, doesnt make sense. pull the glove box out and pull PCM out, open up the hatch on the back and see if the EPROM is aftermarket. Ive seen something similar before with a bad aftermarket program. And at a minimum get the 4 letter code off of the chip.

Is that TDCO a positive or a negative value? If positive that is not good.

Pulse width is too long, should be less than 2.0.

And why is intake air 166 at idle? Is that sensor wrong too, is it drawing air from under hood?

So you have a PCM (or sensors), PMD, or IP issue.
Click to expand...

My idle temp was after i had been driving for 20min to get to the the 195 That is where it normally is the 204 came from sitting with ac on high. i have only had it that high when i was towing at 65mph. What do you mean is there water in it?

The fuel rate is very high. Idk why. Only thing that has been done is a fuel filter and the ip was replaced at 63l in 06. I can almost promise you it is not aftermarket! The PO had owned it since 95 and only replaced the IP window washer module and pmd.

Im not sure at the tdco ill have to check again.

The pulse width is exactly what i saw it at.

Idk it very well could be it is the stock intake. With replaced filter.

Its not the pmd cause i just replaced it littler over a week ago.
as for the pcm or ip idk.
 
Even with AC on it shouldnt get that hot unless the Tstat is opening too late, or you are low on water, or radiator veins are plugged. Maybe too high percentage of antifreeze. Might be time to pull that radiator out and clean it good.

Try unplugging the IAT sensor on top of the intake and see how the truck responds. then unplug the ECT sensor on the tstat crossover and see how the truck responds.

The long pulse width is an IP thing, the fuel metering valve is not closing as fast as it should. Often caused by scoring from not using a good lubricity additive to ULSD.

Try and see how far off the IP flange is from the timing mark on the timing cover. Attached is a picture of it.

I would check the PCM, its not hard, it may not be aftermarket but could be wrong for the application.
 

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Nothing happend when i unplugged the iat. But when i unplugged the ect the rpms jumped up. cant find the ip flange.

How do i get the stupid glove box off?
 
The IP flange is first part of the IPin front of the ESO and against the timing cover.

there is a opening limit cable with a latch in the side of the glove box,slide the latch forward and pull it side ways out its slot,the box cover can than be let down and taken off the hinges.
the box liner is held in with a couple screws,should not be that hard to pull it out.

the IP might have a broke FS pin,the pin closes the metering valve.
 
Multiple problems your vehicle,

1. Desired idle- 638 RPM Ok
2. Engine Speed-600-619-638 Ok
3. Actual IP Timing-26.84-27.37 DEG Bad
4. Desired Injection Timing-5 DEG Bad
5. Measured Injection Timing-4.8-4.9 DEG Bad
For data on 4 & 5 is that in time set mode ??? if not you have big issues as 3 and 4 should match when out of time set in time set mode desired should be 0 with 3.5 deg average
6. TDCO Offset- 0.35 DEG within GM spec -.25 to -.75 if that is a negative value
7. Fuel Rate(at normal warm idle)- 18.12-18.44 (NO SPUTTER) on high side for idle with warmed up engine
8. BARO- 13.61 PSI
9. Intake Air Temp- 166.2F High for an idle IAT
10. Fuel Calibration- 130COUNTS What is this I have never seen this before?
11. Injection Pulse Width- 2.02-2.06 Creeping to limit we recommend looking for a new IP
12. Cam Reference Missed- 0 COUNTS
13. Crank Reference Missed-0 COUNTS
14. ENGINE TEMP AFTER IDLE 15 MIN (with no airlfow) 204.4 you probably have stat-rad-or fan clutch issues
 
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