Diesel Place banner

1 - 11 of 11 Posts

·
Registered
Joined
·
4,805 Posts
Discussion Starter #1 (Edited)
I just got my autoenginuity software today. I've still got a lot of learning to do with it. I was able to get some readings on the IP.

Fuel rate:

Idle 6mm
WOT 62mm (supposed to be 79mm )

TDCO -1.25 ( This is good as it is...yes?)
I adjusted the optic sensor because the fuel rate was low. It was at 4mm. I wasn't really sure that I had restored it to the original scribe mark previously. (I've gotten pretty quick at removing the upper intake and opening up the IP. I can make and adjustment and have it back together in about 10 minutes. I'm getting tired of it though)

Desired and actual IP timing are at 9.1 at idle.


Should I try to adjust optic sensor to achieve 9mm fuel rate at idle?

Also, at WOT truck acts like its running out of fuel. This happened after it came back from the dealer. The tech checked the filter, said it was good, but fuel was "mirky". There are about 8k miles on that fuel filter. Time for another already?

Also, what should fuel pressure be?
 

·
Registered
Joined
·
6,945 Posts
You probably need to call Wester's on your reflashed PCM indications, but:

+8.5 is max I'd use for Base Des\Act timing.

Oem FR is 8-9mm at idle, before the bump, 6-7mm is normal after the bump.

Oem TDCO is -0.5 B4, usually -1.5 after.

Max FR can only be checked under load, as in full acceleration -

how long has the fuel been in the tank?

do you use additives, such as 2-stroke motor oil?

have you tested the Lift Pump, recently?

Fuel pressure at idle is ~4.5psi - full load, oem, will drop to ~2psi.
 

·
Registered
Joined
·
7,135 Posts
It has been discussed here before that a scanner will not display actual fuel rates if you've had a flash done. The scanner will only show within factory range most of the time.
 

·
Registered
Joined
·
4,805 Posts
Discussion Starter #4
You probably need to call Wester's on your reflashed PCM indications, but:

+8.5 is max I'd use for Base Des\Act timing.

Oem FR is 8-9mm at idle, before the bump, 6-7mm is normal after the bump.

Oem TDCO is -0.5 B4, usually -1.5 after.

Max FR can only be checked under load, as in full acceleration -

how long has the fuel been in the tank?

do you use additives, such as 2-stroke motor oil?

have you tested the Lift Pump, recently?

Fuel pressure at idle is ~4.5psi - full load, oem, will drop to ~2psi.
I've emailed wester's about actual specs. I fill up every 2 weeks. Haven't run it real low in a long time. Haven't run any additives in a long time either. tested lift pump 3 weeks ago. I

I checked max fr accellerating up a hill. I'll replace the filter and see what that does. No sense trouble shooting any further until I take care of the obvious.

Sounds to me like I've got to slide the optic sensor back even further. Both fuel rate and timing #'s point towards that.

I hope I get it right tonight. At 5am tomorrow morning we're driving to Florida. It's only 20 hrs:eek: . I think I have to replace the ac compressor tonight, too. The ac system has no pressure, but that's not my concern. The ac clutch rings like a bell at times. :cool: Nothing like doing things at the last minute.
 

·
Registered
Joined
·
1,259 Posts
Just unplug the AC clutch, as a temp measure, If you are worried about having it come apart before you have time to replace it
 

·
Registered
Joined
·
5,861 Posts
Mine seized the day I got home from a trip to Maine. You should have seen the smoke it generated in 2 seconds!!
 

·
Registered
Joined
·
5,245 Posts
Should I try to adjust optic sensor to achieve 9mm fuel rate at idle?

What are you trying to achive more fuel or less?

I paid $415 directly from autoenginuity's website with the GM enhancements. took three days to arrive.
 

·
Registered
Joined
·
4,805 Posts
Discussion Starter #9
Should I try to adjust optic sensor to achieve 9mm fuel rate at idle?

What are you trying to achive more fuel or less?
I'm hoping to get the optic sensor back to factory setting. Not for the purpose of adding or reducing fuel. I need it at factory setting to get the most out of the reflash. Even after moving it back to the original scribe mark, fuel rate at idle reads 6mm.

Maybe I'm reading too much into this?
 

·
Registered
Joined
·
5,245 Posts
Could be. The fuel rate at idle is dependent on TDC Offset as well. I've noticed the fuel rate increases retarded and decreases advanced when you move the pump. I would leave the optic a hair advanced of where you first found it and call it stock.
 

·
Registered
Joined
·
4,805 Posts
Discussion Starter #11
I'm hoping to get to that this weekend. I just got back from a road trip to Orlando, Fl.( I put about 2,400 miles on the truck this week) I'm not ready to get back in the driver's seat yet, even if it's only to pull it into the garage...
 
1 - 11 of 11 Posts
Top