despite what i asked earlyer. We do have lotsa fuel! But still wont turn over-complete start. Its trying like crazy. The o2 sensors we just put in had blk, gry, & wht wires as opposed to stock pkn, brn &?. They looke d identical. p 507 was our code before new sensors were in. could throttle position sensor be a coulperate? Despirate to get on the road. Thanks.

Please keep all your comments about this problem in one topic, instead of spreading them around in new topics. It makes it very difficult to keep up, and it'* harder to help you.

P0507 is a high RPM idle code, which should theoretically be controlled by the PCM in conjunction with the idle air control valve on the throttle body. A faulty throttle position sensor could contribute to poor idle, but if the TPS was seriously out of whack, the PCM would throw a code for that too, I'd think, and would start ignoring the TPS signals until the code was reset.

If you have a multimeter handy, here'* a resistance testing procedure for the IAC valve:

1. Unplug the IAC valve connector.
2. IAC terminals A to B: 40-80 ohms
3. IAC terminals C to D: 40-80 ohms
4. IAC terminals A to C, A to D, B to C, B to D: open circuit (infinite resistance)

Terminal wire colors are as follows, according to Chilton:

A: LT GRN/WHT
B: LT GRN/BLK
C: LT BLU/WHT
D: LT BLU/BLK

You might be able to check whether the TPS is having an effect on starting just by pulling its connector; if the PCM detects an open circuit to the TPS, it'* supposed to default to some safe value.

Don't know if any of this helps, but...

-b

after several more hours of rechecking, we found we mixed up the wires on the new 02 secsor on the cadillac converter, new products wires were, blk, wht,& gry as opposed to stock colors(fixed) pressure checked and found a crack in "T"- not sure part name husband not here to tell me. Must of happened when new plentium went on. We took part off 2nd bonne in back yard(same yr-getting complete over haul). Thanks for pressure specs, will fine tune today and take her for a spin! . Thanks again for all the input.