In reply to porschenut :
Yea, I hear ya.
I am running mine on a computer and harness from a 2007 pontiac g6 gtp (E38 pcm) All of the functions work and it's totally tunable. I paid right at $400 for the ecu, wiring harness, and tune to eliminate any of the VATS stuff.
Got it from Sinister Performance. They do great work!
In reply to wvumtnbkr :
Sinister is a great resource, had an enlightening email conversation with him. Bottom line, with his help I could get the car running again and probably running better than it was last year. Reality of it, I have no interest in learning tunerpro and how to teach this system to run well. And paying him is an option. But it is a 30 year old package, hacked to work in this application. I will go after the harness to check grounds and connections but the credit card will only come out for a new system. I struggled with an ancient efi system on my turbo audi and won't do it again.
If it idles well at 22:1 then it isn't lean, it's a sensor reading issue. Ignore the numbers, chase what makes it happy.
I don't see why it couldn't be converted to adjustable valvetrain, except for valve cover clearance. Those splayed valves might give you fits. Maybe cut an aluminum spacer for under the valve cover?
The kleenex name you're looking for is poly locks. You'll need to convert the rocker bolts to studs. Proper pushrod length is still a key issue so that the rocker tip's travel is centered on the valve stem, but I really hate chasing preload with pushrod length. GM doesn't give you much lifter travel between "too much" and "not enough."
You can also play with rocker pad thickness using shims... again, as long as your geometry is good.
In reply to Curtis73 (Forum Supporter) :
Wouldn't the pedestals keep you from doing much adjustment? Even in the Ford world they didn't try to adjust pedestals, they would either have an adjuster screw on the pushrod end of the rocker like a shaft setup has, or you machine the pedestal flat and go with studs and guide plates like a small block Chevy.
Also, from experience the 8mm bolts used on the 2001(?) up engines liked to pull the threads out of the head even if they were properly torqued. I wouldn't trust them to sit loose. I don't see how you could convert it to studs without a wheel bolt to stud conversion type setup, because of the way the pedestal is shaped.
In reply to Pete. (l33t FS) :
That AFR is crazy lean, but idle at no load might not need much gas. The fact that it flashes a reading in the low teens when the throttle is moved makes me believe it. The wideband narrow band output is hooked to the EFI, one would think telling the EFI that the AFR is that lean would make it go very rich, but not so. I will go thru the wideband wiring and measure outputs of narrow and wide wires, the 22 number does make me wonder but I do think lean running is the problem
On the adjustable valve lash mod, if it was possible someone would be offering a kit by now.
On the super lean AFR, it may not actually be that lean. If it's misfiring it'll show lean due to the extra oxygen in the exhaust.
I'm leaning towards exhaust leak upstream of or even slightly downstream of the sensor, or a defective sensor or sensor controller. An exhaust leak will pull fresh air in through the leak and cause a false lean reading, as will having the sensor too close to the exhaust exit.
By whatever magic, widebands don't seem to be fooled (as much) by misfires the way narrowbands do. My black RX-7 literally misfires half the time at idle and light load (six hits, six misses, over and over.... brap brap brap) and a wideband will read mostly accurately.
Of course, if it's missing because of a stuck fuel injector, then that will cause a lean reading too!
I have never experienced any gasoline engine that would idle well, if even at all, when significantly lean of stoich. The cylinder pressures are far too low to support combustion that lean.. If it has a hot cam it may need to idle at 13:1 or richer to idle smoothly due to internal exhaust dilution.
I am tending to agree with you Pete. But there are no exhaust leaks, no intake leaks and the numbers are coming from an Innovate WB with a new bosch sensor, immediately after calibration. I will check wiring and recalibrate. I think changing focus to an ignition misfire might be a good idea. The coil pack is an old GM V6 one, and poorly mounted. Something may have shaken too much and broke a wire or solder joint. Not sure how to find the source of a misfire on this engine.
Porschenut, a recent issue in my LaSalle (346 V-8 flat head) was very similar to yours. One day it's OK, not perfect, but the next day I staggered around the block hoping to just make it home! I was told the "points were bouncing" What? They're just a spring, it gets old and doesn't hold pressure to the cam on the distributor shaft. New points, condenser and rotor and it's a new car.
I also have a Pertronix Ignition for a 6V Positive ground, but because both wires used are black, I don't know where they go even with the instructions.
Dan
Had a similar issue on an obd1 vw. There was a "never touched" throttle adjustment screw that moved things just enough to get off the idle map an into some other, less runable, black hole in the ecu programming. This doesn't necessarily account for the going down the road problems, but worth checking.
Generally I would agree 22 is too lean for stable idle, but it could be there and very grumpy.
Does it clear up if you give it the beans? Verify fuel pressure at idle and under load?
I am thinking the maps for the ECU have not changed. So it is a signal or something like that. In the driveway it will fatten up when I hit the gas but only for long enough to show on the display. Fuel pressure gage is on the regulator, about 50 psi and never changes. No idea what it is under load but without a dyno that is tough to check.
I keep going back to the old engineering flow chart. Did you touch it? Then that is the problem! The coil board is in a terrible place, getting the connectors on and off interferes with the heater box plumbing. Why do I need a heater in a convertible with no roof? Exactly, so it comes off this week. Then I can mount the coils in a user friendly location and look at all the wiring that is impossible to see with the intake and heater box in the way.
Pete. (l33t FS) said:In reply to Curtis73 (Forum Supporter) :
Wouldn't the pedestals keep you from doing much adjustment? Even in the Ford world they didn't try to adjust pedestals, they would either have an adjuster screw on the pushrod end of the rocker like a shaft setup has, or you machine the pedestal flat and go with studs and guide plates like a small block Chevy.
Also, from experience the 8mm bolts used on the 2001(?) up engines liked to pull the threads out of the head even if they were properly torqued. I wouldn't trust them to sit loose. I don't see how you could convert it to studs without a wheel bolt to stud conversion type setup, because of the way the pedestal is shaped.
Just like a small block, you are eliminating the net-lash bolts holding the rockers. Install studs with the proper torque, then use locking rocker nuts. There isn't anything left loose. It's all torqued to spec.
You use the existing tapped bolt holes for the rocker arm bolts, but install and torque down studs. Then you use polylocks to make it an adjustable preload.
Curtis73 (Forum Supporter) said:Pete. (l33t FS) said:In reply to Curtis73 (Forum Supporter) :
Wouldn't the pedestals keep you from doing much adjustment? Even in the Ford world they didn't try to adjust pedestals, they would either have an adjuster screw on the pushrod end of the rocker like a shaft setup has, or you machine the pedestal flat and go with studs and guide plates like a small block Chevy.
Also, from experience the 8mm bolts used on the 2001(?) up engines liked to pull the threads out of the head even if they were properly torqued. I wouldn't trust them to sit loose. I don't see how you could convert it to studs without a wheel bolt to stud conversion type setup, because of the way the pedestal is shaped.
Just like a small block, you are eliminating the net-lash bolts holding the rockers. Install studs with the proper torque, then use locking rocker nuts. There isn't anything left loose. It's all torqued to spec.
You use the existing tapped bolt holes for the rocker arm bolts, but install and torque down studs. Then you use polylocks to make it an adjustable preload.
You could do that.... if you machined the pedestals flat. These are unique in that they use a slotted pedestal to hold the rocker in the correct orientation. They are.... "different".
In reply to Curtis73 (Forum Supporter) :
Torque them against what, though? The pads aren't flat. And then you'd need to make guideplates and get hardened pushrods.
Keep the existing pedestals. Don't use studs with a hex on them, use straight studs. Like pictured below. You're replacing the bolt with a straight, non-shouldered stud that torques into the head. Slide the pedestal on, slide the rocker on, then use self-aligning rockers. No need for guideplates or hardened pushrods.
If you don't have enough downward adjustment, ditch the pedestals.
In reply to Curtis73 (Forum Supporter) :
Again, if the solution were easy one of the many GM V6 performance parts operations would have offered it. I am leaning towards a ground wire(s) issue, there is one terminal with 6 wires crimped together. The heater box is now on a shelf, so I have room to inspect the harness and make a better mount for the coils as well as a better ground connection. The wiring has been an issue in many places. A 1/0 cable to the alternator had a log held on with heat shrink, no solder no crimp. The battery ground was a cheap 6 AWG from the battery to the battery box, no star washer, no paint scraped off the box.
Supposed to rain this weekend so I can shift from outside chores to the garage. So hopefully it will be running soon.
Giving up. I have gone through all the ground wires, put shielding on the trigger wires, new plugs and wires, run it on the narrow band and the NB output of the wideband. AFR is 22 but it does jump into the teens when I hit the gas but only for a moment. Something is up the the ECU and I am not messing with an OBD 1 system that was hacked to make it work on this car. Paul VR6 is working with me to put a MS3 with all new sensors in. I want a system that has a larger support network. Thanks to all for ideas and support.
You'll need to log in to post.
