Error code 34 on 83 deville

83cadillac · #1 (**permalink**) 06-27-09, 11:30 PM

I get error code 34 and i hear that it is the MAP sensor that has gone bad in it. If so where would it be located. Any help would be great thanks

cadillac_al · #2 (**permalink**) 06-28-09, 11:42 AM

I don't know exactly but they are usually close to the throttle body air cleaner area. It should have a vacuum hose connected to it. You might want to look for vacuum leaks first but MAP sensors do die eventually and yours is quite old. I would replace it for peace of mind if there are no visible vacuum leaks.

carnut · #3 (**permalink**) 06-28-09, 10:17 PM

The MAP sensor is inside the car above the ECM. Rarely fails, but the long plastic pipe from the rear of the throttle body to it can be kinked, broken or the MAP port in the throttle body can be restricted, plugged up from years of carbon. Codes rarely if ever, tell you what to replace. They are to narrow down the search in that sub system only. Is the code a hard code, meaning it displays 3 times on the climate control head? If it displays only 2 or 1 times then its a soft (meaning intermittant) code and should be erased and the car driven to see if it returns first. If its a hard code then visually inspect the pipe I speak of first. I've seen that hose droop and collect moisture ( water) which can cause a MAP sensor failure. On my ELDO, that pipe is attached to a fender brace to keep it from drooping as it passes thru the firewall to the sensor.

83cadillac · #4 (**permalink**) 06-30-09, 11:37 AM

it is a hard code and i have reset the codes about 3 times now and it is the one that always reappears shortly after starting i will check the hoses going to it to see if they are the problem then. Thanks also where would i find a vacuum diagram for my car. Thanks for the help.

carnut · #5 (**permalink**) 07-01-09, 04:20 PM

This is only 1 hose to the MAP sensor. Other than the vacuum diagram under hood any good SMOG test station will have a book with the underhood diagrams. Best bet is the factory service manual. It has ALL the vacuum diagrams, under hood as well as dash.

83cadillac · #6 (**permalink**) 07-09-09, 12:24 AM

thanks for the help

I replaced the vacuum line and that was what the problem was.

carnut · #7 (**permalink**) 07-09-09, 03:55 PM

Thank you for the follow up. now someone else can fix theirs as well. Hose was much cheaper than a MAP sensor huh!!