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running lean on entire pass side bank WTF!

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Lapping compound is the product you use and is available at most parts store by the sealants. The valve holder tool has a suction cup on each end and is also at most parts stores. Also with springs installed you can spray brake cleaner around valve face/bowl and see if they are leaking. Clean both the seat and valve and put layout dye (dykem blue or red) so as you lapping the valve back in you can see the mating surfaces as the cut through the dye. They should be a same width band all the way around the mating surfaces.
 
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I have read about that a little bit. Sort of a oil and compound mix? What have you used?

I use fine valve lapping compound. A LIGHT coat, and spin the valve on the seat. Check the seat location, and the width.
I'd have the machinist do that when he cleans/assembles the heads.

EDIT! treed! nasty has it all laid out.
This slow load nonsense on the board, is causing replies before the entire page is loaded...
 
if the injector banks are wired backwards and running o2 in each bank youll have trouble.one side could read lean and add fuel to the wrong cylinders then those cylinders will read rich on the other wrong o2 sensor and pull fuel so one side could go hell lean and one jhell rich just from wiring wrong even before taking the sequential order mismatch into account
 
a look at a log would confirm it if the corrections are opposite each other one pulling fuel one adding
 
Alky...as for as I know it was working....red light...to green light you know...Gain was at 3 or so.
Gauge, as in boost? Using the boost reading through the E-dash. It was reading 6-10, not ever over this reading during my drive.
I have found that logging fuel pressure on both the fuel rail and alky system to be worth its weight in gold.seeing how your fuel system is working in real time is very important.
 
you have a complicated setup,someone who understands the xfi should walk take a look at your setup very close or you may be repeating this scenario:(
 
Before lapping or taking heads apart, I always remove rockers and fill the port with varsol and see if any leaks out.
 
On boost, unless your injectors are really, really big. the injector is open more than it is closed. so the cylinder assignment in sequential is not very important. the sequential was invented in the OEM stuff for emissions IMO. It carried over into the aftermarket because its easier to get a huge injector to run decently with sequential, and the injector rail dynamics (pressure pulsing in the rail) are better.

that said, how much WOT running did you do in 150 miles? (break-in miles?) knock sensor working?

Bob


Exactly X1000's percent.....

I don't no how many buicks i have worked on over the yrs where the cam sensor 180 degrees out of phase...The only problem i creates with large inj is off idle stumbles and poor idle quality......

Nothing ever happened to the engine like this when at WOT....


Also Was this a alky injected tune? how old is the alky pump has it been tested....... A weak pump will be slow to gain pressure so you will have spool up knock till the alky pump gains pressure after the boost has leveled off.....

What size inj currently running on that single in tank pump ?
 
Yea, I didn't think a carburetor knew the difference between sequential, batch or pour it on. :smuggrin::smuggrin::smuggrin:
 
Probably looking in wrong area as far as fuel pump volume and pressure. if you don't have a problem on the drivers side then its not a fueling issue. you need to be looking at something on that side of the engine like header not sealing up as this can for sure cause pass. bank to run lean and burn valves, or possibly vacuum leak at intake on that side.You have to remember, when diagnosing problems you can eliminate a lot of things by simple elimination, can it be the cam obviously not because it would effect both banks,how about fuel pump nope not effecting both banks, timing, nope not effecting both banks maf sensor well you get the point.Look for something just on that bank exhaust gaskets, intake leaking between manifold and head, o2 sensor on that bank, things along these lines, good luck.
 
Before lapping or taking heads apart, I always remove rockers and fill the port with varsol and see if any leaks out.
lapped one head today. Measured installed height.. Got everything within .005 of each other. The lap looks good, not too much to remove to make a nice positive seal. Painted the heads up, will be assembling it this weekend, the other head is still soaking to get the shit out of the ports. More nice new cometics coming from the factory...they love me by now. I dont even have to give them specs anymore.
 
Probably looking in wrong area as far as fuel pump volume and pressure. if you don't have a problem on the drivers side then its not a fueling issue. you need to be looking at something on that side of the engine like header not sealing up as this can for sure cause pass. bank to run lean and burn valves, or possibly vacuum leak at intake on that side.You have to remember, when diagnosing problems you can eliminate a lot of things by simple elimination, can it be the cam obviously not because it would effect both banks,how about fuel pump nope not effecting both banks, timing, nope not effecting both banks maf sensor well you get the point.Look for something just on that bank exhaust gaskets, intake leaking between manifold and head, o2 sensor on that bank, things along these lines, good luck.
I am questioning the power plate.
 
Exactly X1000's percent.....

I don't no how many buicks i have worked on over the yrs where the cam sensor 180 degrees out of phase...The only problem i creates with large inj is off idle stumbles and poor idle quality......

Nothing ever happened to the engine like this when at WOT....


Also Was this a alky injected tune? how old is the alky pump has it been tested....... A weak pump will be slow to gain pressure so you will have spool up knock till the alky pump gains pressure after the boost has leveled off.....

What size inj currently running on that single in tank pump ?


injectors were 60s and alky yes. Alky pump is 2 years old.
 
Probably looking in wrong area as far as fuel pump volume and pressure. if you don't have a problem on the drivers side then its not a fueling issue. you need to be looking at something on that side of the engine like header not sealing up as this can for sure cause pass. bank to run lean and burn valves, or possibly vacuum leak at intake on that side.You have to remember, when diagnosing problems you can eliminate a lot of things by simple elimination, can it be the cam obviously not because it would effect both banks,how about fuel pump nope not effecting both banks, timing, nope not effecting both banks maf sensor well you get the point.Look for something just on that bank exhaust gaskets, intake leaking between manifold and head, o2 sensor on that bank, things along these lines, good luck.


I agree with alot that you say. I will be replacing the fuel pump because it is "time" You bring up a good points about the header not sealing. I have new TA headers and I questioned them fitting all the way on. It appeared there could have been an exhaust leak, but not sure, as I only drove the car one day before the wheels fell off the wagon. When I took the headers off to look at things during disassembly the bolts were not tightened to 35lb which they were torqued to. I know that you need to do a heat cycle then retq, but I didnt get an chance to do a retq...lol!! I did not use gaskets, and I wonder if I should. Ill probably use the supplied gaskets now, with the ultra copper that I was using on the surfaces as well. I'll probably use studs too. Ill probably take it on myself to seal up the valley pan gasket to the head with a skim coat of grey rtv to insure a good seal. I have never had to do this in the past, but why not...now. The 02 holes are sealed up well, I have two of them.
 
I am 95% sure that you just found your problem, a lot of people don't realize that when you have a leak at header, that during the overlap period both valves are open at the same time and at this time when the piston starts in on the intake stroke it will introduce air from the intake and the exhaust side because the ex. valve is still open trying to get rid of the last of the burnt charge which leans out the cyl. on that hole or those holes where the leaking gasket is.As far as hardware for the headers I use header bolts from percys, best bolts ive ever used torque them and forget them.
 
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