: 83 pulsing gas pedal and codes 27 52 71..

12-08-12, 07:07 AM
Hello all I am new here and could use some help.my 82 eldorado,, has a pulse at the gas pedal and with the pulse is a clicking sound that is synced with it..I also have codes 27 52 71..what do they reference ?

12-08-12, 09:26 AM
WWII, Welcome Aboard !!! Your "reported post" from the adjacent thread (by ehall) went to Admin for administrative action, not maintenance or advice. I posted a request to ehall - maybe he'll reply here or in the thread you reported.

Please keep all posts regarding the same set of problems in one thread, and don't hijack another member's thread.

12-08-12, 11:07 AM
Here's the code lookup -- Cadillac OBD codes (http://www.cadillacforums.com/forums/ht4100-4-1-4-5-4/21558-obd-i-codes-4-x-engines.html)

E27 - Open Throttle Switch Signal
E52 - PCM Memory Reset
E71 - Intermittent MAP Sensor Signal

E52 means your battery died. Ignore it.

E27 means your Idle Speed Controller is defective and has to be replaced. It's the little motorized plunger attached to the throttle body that controls the engine speed when your foot is off the pedal. The switch is inside the ISC, and when the switch goes bad the controller can start doing strange things. This is probably your problem.

MAP sensor tells you the manifold air pressure, the computer uses this value and the air temperature to determine the air density, and then applies the correct fuel to match. This is a simple part to replace, I'd go ahead and do it.

12-08-12, 10:03 PM
Thanks so much for the help gents. I have one more question, how do I eliminate the soot coming out of the exhaust pipe and more over what is causing this unsightly soot. And is there a school here where I can go to learn the ins and out of properly using site..its a great place and I would like to contribute

12-09-12, 11:00 AM
If the MAP sensor signal is intermittent, I would verify the plastic hose to it is intact and not kinked. This hose comes from the rear of the throttle body and should be clipped to the inner fender round brace, passenger side. A MAP sensor malfunction can cause rich running and could be the reason for the soot. Remove the air filter assembly and find this hard plastic hose coming from the rear center of the throttle body. Follow it to the fender brace back to the firewall. Is it in good shape, not kinked? Is is plugged in tightly to the throttle body? With the glove box liner removed, follow this plastic hose to the MAP sensor. Is it secure, is the MAP sensor wiring connector secure on the sensor itself? Are you in over your head? Do you have a factory service manual?

12-10-12, 12:09 PM
Please keep all posts related to this thread within the same thread! The library will not have a factory service manual! I see you have 3 posts regarding the same issues.