1995 cadillac deville

My deville gives me a code po41 so i replaced the hall effect switch in the distributor. Still get the same code even after clearing codes. When i check the codes with engine running i get a po41 current code. starts up ok but get hesitation when taking off from a stop. Please respond if you can offer some input or know how to use the diagnostic controls in dash.

Welcome to AF, there are no in dash diagnostics on this year, codes do not mean to replace parts, you need a shop manual or a subscription to alldata.com to track this down using a step by step diagnostic trouble tree. BTW, you are missing a number in the code.

Sorry took so long to reply. this caddy does have in dash diagnostic readout it is part of the DIC in the instrument panel. You just have to hold down the off and warmer buttons for a few secs and it switches to diagnostic mode that displays trouble codes. Also displays monitoring data as well Do you know a good place to get any books or download info on this system?

If your car has this connector:
http://www.extreme-check-engine-light-codes.com/E-gmcodesetup-1.jpg
then it's OBD1. You can check list of code:

http://www.cadillacforums.com/forums/rwd-19xx-1984-deville-fleetwood-1985/114483-obdi-code-reference-thread.html
Check full page, there's other codes.

You may also find other codes at other sites.

Sorry took so long to reply. this caddy does have in dash diagnostic readout it is part of the DIC in the instrument panel. You just have to hold down the off and warmer buttons for a few secs and it switches to diagnostic mode that displays trouble codes. Also displays monitoring data as well Do you know a good place to get any books or download info on this system?

You guys are correct, there are modern Cads with this capability. Even with obd11. Check this link for some addt'l info. http://www.caddyinfo.com/readingcodes.html

I also have a 1995 Deville. It has the diagnostic connector under the dash and the DIC with the climate control. My question is what information can be obtained from the diagnostic connector that is not displayed on the DIC ? I am getting ready to replace the TPS and would like to know if I can read the TPS voltage adjustments from this connector with a voltmeter. A pinout of this connector would also help.

TPS code should be included in the DIC database. I think only direct stream data is obtained only from the diag connector and not from the DIC.

To test the TPS sensor, it's very simple, don't need a pinout. It has 3 pins, usually in this order: GND, sig, 5V-ref. From GND to 5V-ref you should have 5V. GND is the lowest voltage. The other pin is sig. Easy to figure out.

Backprobe GND and sig with your voltmeter. (Connector should be connected in this test.)
Turn key to ON. You should have less than 1V or so at closed throttle and 5V at full. Voltage increasement should be steady and smoothly.

The 2nd method is test resistance between gnd and sig of sensor w/ harness disconnected and see if it increase smoothly.