I have been going thru the Surging idle checklist to troubleshoot a stalling idle problem and came up with a couple questions
First the problem; after the car is warmed up, and I slow down to a stop , the rpms slightly fluctuate ( not more than 200 in either direction) recover, then lope a bit, and stall out.
My question; While setting base idle and checking voltage on the TPS, I noted that while probing the grn and black wiring.As I sweep the throttle, the voltage would climb from .99v and up while I moved the plate. When I get past about 1/3 the way open ( approx ~2.5v) it becomes an open circuit until I get past approx 3/4 open,then the voltage comes back ( approx 3.4-3.8) and climbs all the way up to full open (approx 4.6-4.8v)
Is the open circuit ( no voltage value) between ~1/3 to ~3/4 throttle normal operation for this tps?
I tried another I had laying around and nearly the same thing.
I am inclined to think it is NOT. But two doing the same thing? what the heck?
BTW, I am not seeing any codes,
I have fixed all the vacuum leaks I can find, even a doosie in the brake booter I replaced, All the grounds mentioned in the checklist have been verified, or re-terminated.
The speed sensor in the trans is new, as well as both o2 sensors, and the injector engine wire looms are new ( NOS)
Other then stalling out when warm, It runs well, just missing some power around 2800-3800
91 fox 5.0 stock block/ AFR 160 heads, ford e-cam , manual 5 speed, Cobra upper/lower intake, 24# injectors, with matched and clocked C&n MAF that is taking air from the wheel well. ( clocking the maf made quite a difference ), and all emission related parts were lost
timing , is 13deg spout out, 93oct gas , FPSI is 32#'s
thanks for any help,
First the problem; after the car is warmed up, and I slow down to a stop , the rpms slightly fluctuate ( not more than 200 in either direction) recover, then lope a bit, and stall out.
My question; While setting base idle and checking voltage on the TPS, I noted that while probing the grn and black wiring.As I sweep the throttle, the voltage would climb from .99v and up while I moved the plate. When I get past about 1/3 the way open ( approx ~2.5v) it becomes an open circuit until I get past approx 3/4 open,then the voltage comes back ( approx 3.4-3.8) and climbs all the way up to full open (approx 4.6-4.8v)
Is the open circuit ( no voltage value) between ~1/3 to ~3/4 throttle normal operation for this tps?
I tried another I had laying around and nearly the same thing.
I am inclined to think it is NOT. But two doing the same thing? what the heck?
BTW, I am not seeing any codes,
I have fixed all the vacuum leaks I can find, even a doosie in the brake booter I replaced, All the grounds mentioned in the checklist have been verified, or re-terminated.
The speed sensor in the trans is new, as well as both o2 sensors, and the injector engine wire looms are new ( NOS)
Other then stalling out when warm, It runs well, just missing some power around 2800-3800
91 fox 5.0 stock block/ AFR 160 heads, ford e-cam , manual 5 speed, Cobra upper/lower intake, 24# injectors, with matched and clocked C&n MAF that is taking air from the wheel well. ( clocking the maf made quite a difference ), and all emission related parts were lost
timing , is 13deg spout out, 93oct gas , FPSI is 32#'s
thanks for any help,