1996 Buick LeSabre Diagnostic Help Requested

[4beussinks]

I have a 1996 LeSabre with just under 138K miles on it. I am the 2nd owner, and the 1st owner is a family friend so I know it has been well maintained since day 1. I have a few issues that I am trying to diagnose, thanks in advance for any help given.

1) It occassionally stalls when I try to put it in gear from park, and has for a few years. It has happened so rarely and always without a check engine light staying on that I have ignored it until now.

2) Sometimes while sitting idling the RPMs will surge from around 800 RPMs to 1500+ RPMs without hitting the gas, stay higher for a minute or 2, then lower back down.

3) I hear a strange noise (like fan blades hitting something) sometimes when I turn on the defrost. It isn't the heater or a/c, as I can switch them on and not hear it until I turn on the defrost, then when I turn the defrost back off but leave the heater or a/c on the noise goes away.

4) Finally, the front passenger door lock doesn't respond to the key fob or auto lock on the driver's door, I have to manually lock/unlock it.

Once again, thank you for reading and any help/advice you can offer.

 

[journeyforce]

For the first issue, it most likely is a sticking IAC. Sometimes they get gunk in them and are slow to react. Clean it out and it sould be good to go

Same answer for #2 question

For the lock, try replacing the door lock actuator on that door

 

[Joe3301955]

We are talking 1996 here, that is 16 years old.
2) Check the vacuum hoses for cracks especially where the hose has to expand a little to go on a fitting. You should take the hose off each fitting (1 at a time) to check for cracks.
3) The AC compressor turns on automatically when the defroster is switched on. With the engine running and defrost turned on, look at the AC compressor and clutch under the hood (just look). Maybe the AC system could use some oil inside the system.
4) Assuming the electric window works which indicates the door is grounded that does not leave much left.

 

[dcraig1000]

if you are going to check for vacuum leaks, take a can of carb cleaner or throttle body cleaner and spray all the vacuum connections and around the intake. if the idle changing(revs), then you found a leak.