So, this '85 Park Avenue I just picked up runs pretty poorly. When the engine is cold, it won't idle, if I turn the A/C on, that helps it idle a little bit. I experience what can best be described as power surges and losses while driving it above 45mph. It feels kind of like suddenly pulling a 4,000 lb trailer behind it, then the trailer suddenly dissapearing. When the engine warms up, this problem isn't quite as bad. I just ran injector cleaner through it, it helped a little bit. Today I was driving down the road at 55, then it started losing power, and slowing down, I floored it, it made a little more noise, picked up a little speed, then continued slowing down, by the time i slowed down to 38, i down shifted it to 2nd, and it didn't help, it still was slowing down, by the time it made it down to 35, what ever was causing it let up, and i was able to get it back to 45mph. I disconnected the MAF sensor, and haven't had that problem since. Upon reconnecting the sensor, if the engine was running, it dies as soon as contact is made. disconnecting it while the engine is running doesn't affect idle at all. Anyone have any ideas on this?

 

Your MAF sensor may be dead. When you disconnect it the computer use a
default value of air flow to control the gaz mixture and other thing...

When you plug it on a running motor, the computer see a huge change and try to correct ..... thats why the motor die

 

any codes? Have you checked the pressure regulater for fuel on the vacume side common problem. Catoltic converter pluged. O2 sensor been replaced reacently(20,000-30,000 miles) mabey stuck and trimming fuel in wrong direction.

 

You might try checking the fuel pressure, which would cause lean mixtures when cold, or under heavy loads, such as heavy throttle, passing etc. Ray

 

My apologies for not completely reading this post. These vehicles were known for problems with air flow meters. You might try tapping on the meter, checking for the usual surging, erratic operation, or stalling that comes from the erratic air flow readings when the meter fails. Ray

 

I'd say it sounds like a maf. or is that map? yours would be a map costing about $85, mine was a map costing about $500 lol.


But yeah mine did the same thing started not so bad, then got worse over a month or so, cars are made to be failsafe so it goes into a limphome mode, so you can get it home, it richens out the fule mixture quite a bit, if your exhaust smells like gas, u get bad gas milage, stuff like that. the first moth it was off and on, then after a month it was just plain crap.


Replaced the part, reset the computer, and she runs like a dream.