wrd1972

Got my new motor running pretty darn good, but the right side BLM is very high on the right side only. The left side appears to be acceptable. I am getting this info off my Scanmaster, I also have Datamaster TTS but ve not completed a log yet, but I can this weekend if the problem remains.

From the way I understand it the right side O2 sensor is seing more un-burnt oxygen than it should. Also the problem is most likely not coming from anything in front of the throttle body or both sides would be affected.

I have been troubleshooting the right side of the engine. Here is what I have checked:
Switched the two O2 sensors, problem remains so sensors are good, left side was a bit more black than the right.

Did not check O2 extensions, but would guess thaey are good, O2's are behaving normal.

Checked plug wires, they are on good.

Plugs are new.

Sprayed starter fluid around the intake fittings and openings, nothing happened.

Checked FPR vaccum fitting, it is good.

Checked EVAP solenoid rubber hose, it is cracked and being replaced. I dont think air was getting sucked in through the cracked rubber hose.

Checked header gasket, good there.

Checked collector gasket, good there too.

Pulled plug from left and right, both look normal.

I can find any smoking guns on the right side of the engine to be messing up the BLM's this much.
I thought I once remember someone saying the the L & R BLM's as shown on the Scanmaster were reversed, meaning when you are viewing the left it is measuring the right. Can anyone confirm this?

Anyone have any other suggestions?
Thanks in advance.

96flame

All it would take is to have one injector that isn't spraying the proper amount of fuel. The pcm is adding additional fuel to try and compensate. Are the injectors new? flowmatched?

wrd1972

It was suggested to me today that it might be injectors.
I bought the injetors used a good while back too. Anyway I just got finished pulling the fuel rail off and testing them. I had the fuel rail hooked up to the fuel lines outside of the car and I was testing them with a power supply. I was priming the rail and applying voltage to the injectors to force them open and I payed close attention to the spray. I think doing this may have also helped to clean them out some.

Two of them that came from the right side I suspect may have an issue. The pattern deteriorated some as the rail ran low on pressure. I also switched the left injectors to the right side and vice versa.

After driving I noticed that they are much closer to each other according to the BLM's. It also appeared that the bulk of the problems are cell 16 and not when on the gas. Anyway the the BLM's definitely changed so I think it is safe to say that my injectors have issues. I will get a new set maybe next week. I want to drive on them a few days then I will get a datalog.

96flame

If its only closed throttle it could just be reversion of exhaust gases in the intake because of the cam throwing off the oxygen sensors. I have high blm's when closed throttle aswell.

wrd1972

Okay, I still cant find why the right side BLM's are 150-160 or so.
The right side bank on my new engine is still showing 150-160 BLM's at idle and deceleration or basically anytime the throttle body is closed.
Here is a snapshot of my fuel cells:
Cell LBLM RBLM
2 135 148
3 130 138
6 127 127
7 121 118
10 128 121
11 126 123
15 128 128
16 135 160
17 130 150
18 130 145

Again I have done all this:
I have checked for exhaust leaks, none apparent.
I have swapped the fuel injectors, left to right etc. no change.
I have looked for intake vaccum leaks, no apparent.
I swapped the O2's, no change.
I sprayed the intake openings with starter fluid, no change.
I checked the plugs, look normal with no blackness.
I checked the plug wires, look good.
The opti, plugs are all new.

Is this the cursed split BLM's?
Will the dyno tune cure this?
Any other thoughts.
Thanks.

wrd1972

bump

fireman

My car did the same thing after the motor was built. Its just the big cam. After a good dyno tune, the big split went away. They are still split, just closer together now. Now, instead of the right being way high, its in the 120s, and my left gets kinda low. You are never gonna get them dead on even.
I also installed a BLM locker so that they both lock at 128 when going WOT.