IHADAV8.com - Turbo Buick Tech, and Nonsense
Tech Area => General Buick Tech => Topic started by: 84 BuickGNYorkPA on September 06 2013, 05:11:29 PM
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Hi Guys,
Out of the blue I find myself seeing knock at WOT, in the past this has always told me it's time to replace the fuel pump. So 1st I replaced the filter with "Driveworks" fuel filter, as it was the only one in stock, still going lean in the gas. Checked the fuel pressure at the winshield while driving and had the 1 pound of fuel pressure for each pound of boost, now scratching my head and figure, well only one more thing to do... So next drop the tank and put a new Walbro pump in that I had new since the big Walbro incident a few yrs ago, where you sent in your defective s/n pump and they sent you a new one, guess what still have issue. Running the SD chip and it's showing the chip is trying to add the max fuel, so strange. Any ideas what might be going on? Going to replace the fuel filter again with a Puralator, but don't think that's it... Was thinking maybe the fuel regulator? Not sure....
Chuck
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If the FP is rising 1:1 with the boost - what makes you think it's a fuel problem? What's your O2 at WOT?
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are you using a wb to drive the chip?
Are you spraying alky?
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SuperSix, it rises good staying in the 11.0 A/F ratio range, then as the rpm's build into the 4500 or so the A/F drops to 14 and I get out of it, glance at the scanmaster recall and it shows 22.1 :icon_redface:
Steve,
Using wb to do chip correction, not sure if it's driving the chip, spraying alky, when it's at idle and I hit the test button the a/f dives into the single digits. I do have a gage I could put on the alky and check the pressure...
I have to run to a football game and watch my son in the marching band, I'll check the board later tonight and replace that fuel filter tomorrow with a puralator, keep the questions/comments coming...
Chuck
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okay...so we don't know if it is a wb problem or an alky problem...or something else.
If it were me, I would turn off the wb in the chip and try it open loop first. I think we can probably eliminate the fuel pump if the pressure is doing the 1 for 1 bit.
and, unfortunately, the test button on the controller only sprays a minute amount compared to full blast so we cannot say the alky is working right without some kinda pressure reading out of the pump...makes it hard to troubleshoot
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if fuel pressure held and wideband is correct and it truely went lean then its not burning on all 6 or your injectors are being underdriven
check the plugs and wires ,
i know you are on TR6 but check the coilpack anyway
verify the inj duty is correct +25 we know but what was the commanded vs end result
check for a loose inj connector
could be as simple defective o2 and its low reading is driving the fueling off (rich ) and causing kR from the excessive fueling
wouldnt be the first time with wideband control
are you logging alky pressure ?? might be time for a pump checkup
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Steve,
Have not checked the 1 to 1 with the new pump (need to do that), I have a alky pressure test kit, used it to test the pump when it was new last March, don't remember the value, may have it written down in the test kit box. Will check that tomorrow, may have to reach out to Julio to see what pressure I should be looking for. Will look at the chip next and see if I can turn off the wide band and run on speed density only.
Paul,
Never put the TR6 back on the car after the Ohio trip, have a new coil mounted to it and it's ready to go on, was keeping it as the spare, so I could try that.
When you say to verify the injector duty cycle is correct, I assume you want me to hook the laptop up to the power logger and check the duty cycle in the lean condition.
I will check the fuel injector connections, take them off and add some die electric to each connection.
Wouldn't surprise me though if it's the alky pump going south.... I'll update this post tomorrow, thanks again guys !!!
Chuck
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would think that if it was misfiring to that extent, a miss would be evident.
The wb uses the a/f of the alky plus the gasoline when measuring, but, it only controls the gasoline via the pulse width. So if the alky is not there in quantity, it will peg the injectors trying to achieve the designated a/f programmed into the chip.
As you believed you had the proper pressure increase, I figured it was probably the alky...but, if you have not checked since changing the pump...be a good idea to verify that is still the case
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according to FB, his alky pump tested weak
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Alky pump pushing 85 psi, Paul replaced a pump that was 135 psi and the new one tested at 165 psi.
Chuck
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Not sure if the test is at full pressure, or not, but I thought they were claimed to be over 150 in the ads
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It would be hard to get used to but, I may tune the car for 15/16 lbs and just run it with out alky.... see how long I can stand the lower h/p. At alky control dot com, pictures show over 250 psi.
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That will last until the first time you drive the car! :D
I find it hard to believe that the pump would maintain that pressure very long..but I have no experience with one so I really cannot say I know :)
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Just talked to Julio and he told me to check at the control box (the one under the dash) for 12 volts and check the ground and make sure the ground is not loose. He said the pump should be leaking if it's only putting out 85 psi. But I promised my better half to do stuff at her house this evening... I should get to it tomorrow.
Chuck
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Be nice if it was something simple like that.....:)
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i retested mine again and sent the vid to chuck
at under 12v (engine off on a weak battery )
alky tetser maf simulator at 22-30 psi ,
tested with a single m15 nozzle and 100% methanol
gauge read 150psi with only a couple psi fluctuation
my personal settings were at
gain knob 5.5 ,
inside the box .. turnon at 10:00 (8-9psi) initial at 11:30 ( i run two M10nozzles)
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Showing 8.65 volts at the box under the dash, the positive wire ohm's out but the negative wire doesn't, will look at it more tomorrow.
Chuck
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Sounds like it's going to be a cheap fix!
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Volts going in to the controller 12 volts, volts going out with the reastat turned to max (alky flow knob) 8.6 and alky flowing back into alky tank with pressure test kit. Next unhook pump from the system, 12.0 volts coming out of the control box with reastat maxed out. Next test, hook the pump up direct to the 12 volt battery, battery dropped to 11.7 volts, pump pressure = 100 psi.
Chuck
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If I understand correctly, you should see a lot more than that
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where are you grounding at
the pump runs by regulating the ground with a pmw controller
reading 12v at pump is one thing but if the ground is weak the pump will never run well with load
check your grounding and your connections to pump and at the controller
i use the 10mm grounding bolt on the lower edge of the dash just beside the courtesy bulb where the main dash harness ground is
good idea to run a ground (12gauge) from there to the fender by battery
12v across a meter doesnt mean much unless you read it using the ground at amperage
you can have a a wire connection thats shows good on a meter when tested with milliamp of the tester battery but when hit with a load is no good
i usually have the alky tester (and ignition tester) with me at the meets
if you make it out to Cecil (Northeast Buick nationals /magna car sho)we can test it with my setup , if not there maybe at Kirbans open house
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ill tell you this chuck
as much as i believe your alky pump is running lower than normal it was running
what i dont see is how with 85psi of alky you were off on fueling by over 25%
the pump wasnt and currently isnt capable of displacing that much fuel even with duals
theres more to this than we are seeing unless you were pushing the car and getting nothing from the pump
im sure youve heard from murphs loggings to keep the bucket full or it will cavitate (wont happen on a dyno of course)
i would be looking into the SD program a little more and look for a setting that lowered the injector duty, or for misfire
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So alkycontrol is PWM lowside switching?
THAT will take some education for the regular user to troubleshoot.
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I think alky control suggests that the pump be rebuilt every couple of years
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Paul,
I ran a ground wire to the firewall, for the tests, (borrowed the one hooked to the wideband and scanmaster, made no difference) which is a ground kit from the block.
Under the dash is a nightmare, wires from the alkycontrol kit, scanmaster, wideband, knock sensor, A/F ratio gage, turbo/vacuum gage, it really needs a dedicated power and ground strip. Also been having issues with the wiper fuse socket for many years. Thinking I should find/buy a new fuse block, or what ever that thing is called that holds all the fuses and redo it all.
At this point I'm sure that the pump is bad, and possibly the controller, so now I have two pumps, one that leaks and puts out 65 and one that puts out 100 wired direct to the battery. I spent the extra money last year to buy a new pump thinking a new pump should give me another 3 years like the 1st one, well I got a year and a half out of it anyway.
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Update: The root of the problem was a bad Innovative LC-1 wide band. Just got around to installing the new PLX system yesterday that I scored on ebay for about $100 a few weeks ago, what a difference. Started the car a/f solid as a rock at idle, looked at the vacuum gauge and it wasn't moving. Thought that I must have knocked the hose off of it, so I tap the gas pedal and it moved, car idled smooth :) Looking at the SD2 ver 1.1 chip on the bench and thought well, days going pretty well so might as well go for it, and more good news, car is back, both Alky pumps are packed and ready for shipment tomorrow back to Julio, so the boost is turned down to 18, but after a couple of test runs, the tune is very close already, pretty sure that if I put that 95 psi alky pump back on, I could be back to 25 lbs boost, but it goes in the USPS system tomorrow, hope to see it back in about 3/4 weeks. Car does not go lean anymore, bad O2 system = bad input = bad output = crazy O2 readings?
Chuck
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wide bands have made me appreciate open loop chips!