Still have not found Gizmo running around in the wiring yet. The car has not acted weird since that last time, but since I haven't found anything or fixed anything....he will be back.
Now that things have settled down a bit around the house, I'm hoping to be able to get a move on the rest of the car and make some actual progress on it.
I haven't completely done nothing to it as I have been driving it to try and work out some operability issues with the FAST EFI. Besides the MAP sensor that failed on me in the first 100 miles, I have not had any other issues with the mechanical side of this system. Where the largest problem has been is in part throttle running. Under "normal"......maybe for a minivan.....driving conditions, she runs and drives like a dream but if I decide to roll heavy into the throttle, like an on ramp to the interstate, the thing bucks and coughs like a bronco and never seems to pull out of it until I let off the throttle and roll light into the throttle. I can also forget about roasting the tires from a stop also as it has about the same effect.
Since the tech line is not much help, I scour the forums for any relevant information pertaining to this issue. What I found was little to nothing on this issue so it looks like I'm pretty much on my own to figure this one out. The advice usually boiled down to 3 things which were: 1) Send the ECU into FAST for evaluation, 2) Check all sensor values during an abnormal event 3) Check for exhaust leaks. That seems to be the main theme for any issue that arises with this system, and then little help is given past those checks besides find the settings your motor/car like.
So.......I guess it's time to try and figure this out.
Like everything else, these checks and tests must be done with a fully warmed up engine so I take her out for a leisurely Sunday stroll and get her nice and warm.
Get back to the house and begin to run it through the setup wizard again. I chose to not reset the ECU to the base tune as that would wipe out any information it has compiled to date. Maybe I should have, but I didn't at this time. I input the information it asks for regarding motor, fuel pressure idle rpm and so on, recalibrate the TPS and start the car as instructed. While it is running, the IAC needs to be adjusted into its target range window and I find it is pretty far out. I adjust the throttle blades into the target zone, which effectively puts them a bit more open than they were when I started. There is a bit of conflicting information in the forums on this as some guys say to use this feature, other guys say to tune this afterwards using the display on the handheld and set it to around 14 counts at idle. Setting it using the target window, I'm showing counts of 22 or so.
Once I set that, I verified function of the TPS. The operation is smooth with 0 being closed and 100 being open. It was proportionate to the amount of throttle given and I also verified that the throttle blades were opening fully at full throttle. They were.
Checked all parameters for A/F ratios and they were as follows:
Idle - 13.5
Cruise - 14.0
WOT - 12.5
Accel "shot" - 0
Took her out for a spin and again pretty much fell on its face and bucked hard enough to break stuff in the drivetrain. A quick glance at the handheld showed that the immediate sensors were functioning correctly, but the A/F was all over the map. From the initial buck, it dropped to a 10.?, jumped to a 15.?, then back down to the 13's. All of this happened in milliseconds so the numbers might be off a bit. Judging by the first reading I got, I guessed that I was going rich causing the initial bog and buck. I changed the accel shot down to a -2 and tried again. No real change in the issue.
I got to thinking about the readings each time this happened and it always spiked lean after the initial rich reading and started wondering if in fact I'm going lean, not rich, and it's a bit delayed to display on the handheld. I bumped the shot up to a +3 and tried again. That made a significant difference but did not fully eliminate the buck. What it did though, is work past the buck quickly and enabled me to stab the gas and take off like a rocket. This was something I was not able to do before so I must be heading in the right direction.
I came to a stop sign and decided to give her a romp. A quick stutter and she took off and roasted them. By this time it was 9:30 pm and not only did I have go to bed since 4 am comes early, I figured no need in keeping the new neighborhood awake as it is so quiet there, you can hear a flea fart.
I'm still having a bit of a bucking issue in the transition area of cruise/wot so what I think I need to do is work on the A/F ratios there, instead of the accel shot, and see if maybe making cruise a little richer will help the transition smooth out. 14.0 might be too lean for this car and be too large of a gap from cruise to wot.
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