: what to do next after a MAP/BARO code?



85fltwdbrougham
03-30-06, 09:55 PM
First timer on a GM (http://www.cadillacforums.com/forums/#) forum, but certainly admire the help and advice. Thank you in advance.
I have a 4.1 85 fleetwood. It runs, but ALWAYS have cars (http://www.cadillacforums.com/forums/#) line up behind me when i go up any hill.
I ran the simple codes, and got a MAP/BARO correlation code, and have to get it smogged soon as my registration runs out. THe check engine (http://www.cadillacforums.com/forums/#) light came on when I got the car (http://www.cadillacforums.com/forums/#) 5 months ago, but is on all the time now. I've replaced the plugs, cap, rotor, air filter and wire. I have NO CLUE what to do next.
A) are there other diagnostic checks i can run on my climate control that will test the condition of each one of these two sensors seperately (MAP & BARO)?
B) Do i have to just buy and replace one sensor, and if that doesn't work, but the other and replace it?
C) Could i have a clogging cat?
****more info: it sputters pretty bad whenever I depress the accelerator more than half way 'off-the-line'. And will sputter of I depress past a certain point, which is relational to the engine speed (the level will go closer to the floor, as the speed of the engine increases). When I floor it on the highway, it goes slower in the gear it kicks down to!! (WTF?)****
D) OTHER?!?

I love the cad. People really don't know what to think, so they don't give any negative pre-concieved notions, unlike most cars out there. ANyhow, time to got to bed! (it's 2.30am here in Monterey, ca.). Please help. SOS.:confused:

carnut
04-03-06, 10:14 PM
If by SPUTTERING, you mean makes a pop/pop noise when you accelerate, then remove the air cleaner lid and depress the throttle slowly in gear with your other foot firmly on the brake. If it pop/pops thru the throttle body then its probably a "flat cam lobe" and the cam and lifters need replaced. This engine can leak coolant into the crankcase and the coolant will wash the oil off the cam causing it to wear rapidly. The usual suspect is the intake gaskets corroding away at the rear of the engine from not changing coolant every 24 months and adding the MANTATORY coolant pellets mentioned on the plate in front of the radiator. The MAP/BARO codes could be because they are ingesting coolant thru the vacuuum hose connection? Good Luck!

jsp2002
05-12-06, 11:57 AM
I have been having the same problems with my 85 flt, brougham. Just curious to see if you got it fixed and what the problem was.

N0DIH
05-12-06, 04:59 PM
Sounds like the MAP sensor is bad or the hose is bad (which is very likely with the age, check the hoses).

I would lean that way for sure. If the MAP is bad it will toss a code and ignore the data on it. So if it is running lean or timing is off, it will pop through carb/throttle body. And as Carnut said, worst come to worse, the cam. With the newer modern SM spec oils, there has been a rash of camshaft failures do to the oil. DO NOT RUN ANY SM spec oil in flat tappet cars if you want to keep the lifters alive. Run 15W40 CI-4 Spec oil only. You can thank me later.... And the old Bobster who pushed it. He at least knew something lol lol lol lol .......

Just do a search on these forums (mainly the HT4100 forums) for lol and zddp, you'll find a lot. Oh, synthetic too.... Even synthetic SM oils don't protect like CI-4 oils do. CI-5 is coming and it is going the way of SM, so avoid......