reversing issue please help

[jaymz81]

hello all, i am new to this site but not really all that new to the v6 3.1 L engine but here is my problem

I have a 98 Grand Am SE 3100 series, and when i lets say go to back into my spot at my apartment or work, the temp gauge goes into the cold position and the rpm revs to about 1500-2000 rpm, but when i put it in park or drive everything seems to even out so this is an only reverse issue hense the title or the thread, if anyone can give me suggestions or any insight into this problem it would be awsome!!!

[96ols60degree]

Sounds like you have two or more things going on here. Check all your grounds to your instrument cluster,make sure your coolant tempature swicth is good and hooked up properly too,because that switch sends signals to your pcm that relates to how your engine runs.that is were i would start.also check your cooling system thouroghly,that also means check your oil , making sure your coolant isnt in it.when my lim gasket was going bad,the engine temp would go up and down,and so would the engine rpm's for some reason.

[jaymz81]

yeah, i just replaced the coolant temp sensor a couple months ago...i was talking to my mom and she has a chiltons or haynes book on a grand prix which in the book talks about the 3100 series engine and i told her when i drive the car and go to lets saya store or mall, when i get back to the car the engine is still warm when i go and start it, it wont start right away, so she looked that up in trouble shooting, under the title wont start when hot or something of that nature it says to check the battery ground....do you think it could have something to do with that? and i have checked the oil and it is normal, engine coolant levels are normal and all, thanks for your response though!

[96ols60degree]

OK,now you got me a little confused?So when you are trying to start it,just how long does it crank? Because your starting problem sounds like it is not getting fuel,hense fuel pump,or fuel injectors leaking down,these 3100's are common for this injector problem,mine does this in the hot weather.The temp gauge thing is still puzzling me,still think it has to be a ground.Sorry,anyway,whem these older style injectors get old,they will leak gas into your cylinders,making it hard for you to start.please reply back.

[96ols60degree]

Just real quick,I take it this thing has had proper tune ups and all?one other thing that comes to mind is your ignition module that sits under your coil packs,these have been known to cause this problem on these quite frequently.

[jaymz81]

well the tune up i gave it is new plugs and wires, the starting problem is only when the engine is hot...been running for a little bit, going to store or whatever, it takes a big to crank over when i do this, when the engine is cold it starts up no problem, we had a really nice weather snaps here recently and the car was beautiful, no problems what so ever,, reverse worked great, starting up when i went out was no problem...now it is below 0 celcius it's being dumb again...i never had a chance to check the ground but once i get a chance i will, i can hear the fuel pump humming when i start the engine but a guy on another forum told me that that was normal...i never heard a fuel pump like that before...i don't think it is normal