No1Dad wrote: ↑Thu Sep 01, 2022 9:28 am
Update on the sluggish accel issue:
1)The TPS now reads exactly at .44
2)Timing was 5 degrees off and using a timing light I got it at 15 on the money.
3)IAC duty cycle remains at 10%
4)Oxygen sensors seem to be getting worse. Bank 1 is much less active even under acceleration so I want to get that taken care of ASAP. HOWEVER, I see that they're situated on the dreaded bungs. This car has much less rust than others that I've worked on but I have not had a single positive experience with these nuts TBH. the position they're in is also concerning....
As for the injectors apparently I had given the subharmess a once over already. I noticed that the pins had been scrubbed and resistance was fine.
Overall the car is much more responsive. It no longer crawls from a stop but as you can imagine the acceleration is still severely lacking sometimes. When it works properly it does not fail to put a smile on my face. I'm almost there in terms of performance. I can feel it.
1) good
2) smart to use timing light. Remember, your scan tool doesn't know where the base timing is set. That's why you use the light. Most scan tools I've seen quote 15deg on the screen when the ECU is calling for zero degrees of timing adjustment. The scan tools
assume the user has set the base idle to 15, and "matches" that. then, as the ECU adds or subtracts the timing, the scan tool should match. So if your scan tool is reading 5 deg even when your base timing is set to 15, it sounds like something is telling the ECU to take out 10 deg of advance.
3) good, but.....a lot of scan tools I've seen say 10% duty even when it's zero. like 10% is the lower limit from the ECU mapping table. Which is why I suggested 11-15%, to force it off the lower stop.
Verify that when you slap it in gear, the IAC duty jumps up (20-ish percent). same with AC switched on. It' should run a higher duty to keep the revs at about 650 at idle when you put on the loads of AC/Alternator charging/drive gear.
4) as others have said, replacing is not too bad on the G50, just remember they are unforgiving if you round off the hex corners, so take your time and soak them as suggested, and have a TIGHT fitting crowfoot on there. When you say "much less active under acceleration", I would expect the O2s to both go lean when you smack the pedal, and maybe eventually the injectors will richen up enough to come out of O2 lean saturation as you get close to redline. And, of course, when you let off the throttle, they will peg rich until the fuel cutoff smooths things out. I suggest checking the rapid cycling of lean-->rich-->lean etc. under part throttle cruise, with constant throttle position, but not really accelerating or decelerating. THAT is where you should see the rapid cycling.