Spark plugs burning uneven - Pics Included!

BLKHAWK said:
Ok I'll ask agian. It has an LS1 P59 controller on an LT1 correct? you need to change the injector to bank assignment. I use one out of a 2002 express Van.
Click to expand...

You dont have to change the injector to bank assignment if the car is in open loop (which it is)

straight from EFI Connection:

If the engine is intended to run in closed loop, be sure to change the Injector to Bank Assignment table to assign
injectors to their appropriate banks.


This is also from EFI, not sure what it means exactly though:

Make any necessary fuel injector flow rate changes. Pay attention to the injector flow rate of the LS1 injectors. The
98-newer LS engines do not use a vacuum operated fuel pressure regulator, so the injector flow rate is a sloping
value. If your engine is equipped with a vacuum controlled fuel pressure regulator (TPI and LT1 engines), then the
injector flow rate should be set as a constant.
 
ThreeHonks said:
You dont have to change the injector to bank assignment if the car is in open loop (which it is)

straight from EFI Connection:

If the engine is intended to run in closed loop, be sure to change the Injector to Bank Assignment table to assign
injectors to their appropriate banks.


This is also from EFI, not sure what it means exactly though:

Make any necessary fuel injector flow rate changes. Pay attention to the injector flow rate of the LS1 injectors. The
98-newer LS engines do not use a vacuum operated fuel pressure regulator, so the injector flow rate is a sloping
value. If your engine is equipped with a vacuum controlled fuel pressure regulator (TPI and LT1 engines), then the
injector flow rate should be set as a constant.
Click to expand...

the non vacuum referenced regulator system has a constant fuel pressure, and since the difference from the fuel rail to the intake absolute pressure(generally called "vacuum", even though it isn't) changes, the effective fuel pressure is a slope(not the same differential pressure from idle to WOT), so, it needs more pulse width @ WOT to get the same fuel volume as opposed to a vacuum referenced one, which has less pressure with vacuum, also, more pressure with less vacuum, so the differential pressure is similar from idle to WOT, this system needs less pulse width @ WOT then the other system, and the injector constant remains the same thoughout the operating range
 
The factory lt1 pcm has 2 tables which handle dealing with cylinder fuel trim. The only way to *fix* the problem is to adress the intake plenum.

As for the injector constant, depends on the fuel pressure regulation. but its not a big deal.
 
Sean said:
The factory lt1 pcm has 2 tables which handle dealing with cylinder fuel trim. The only way to *fix* the problem is to adress the intake plenum.

As for the injector constant, depends on the fuel pressure regulation. but its not a big deal.
Click to expand...

This car runs on an LS1 with coil packs. Opti is totally gone.

Phil sent me a Beta HPT file that I uploaded. :) I also put new plugs in, so only time will tell
 
ThreeHonks said:
This car runs on an LS1 with coil packs. Opti is totally gone.

Phil sent me a Beta HPT file that I uploaded. :) I also put new plugs in, so only time will tell
Click to expand...

the lt1 pcm had software that adressed the issue with the air distrobution problem. to fix your issue you'd have to graft that into your new tune file.
 
Figured I would update this:

The injectors were wired wrong. #2 was opening when #3 was suppossed to be getting fuel smae thing goes with cylinder number 4 and 7. I have not had a chance to run it enough to get a reading on the new plugs, but I would imagine this was the problem for them burning uneven
 
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