Problems with a 93 Grand Prix LE..

**thehollowaytape** · 05-10-2010

Hey guys, I thought I'd finally join here after lurking for a while.

I have been having a couple of huge problems. I'm no mechanic but I can replace some stuff (alternator, etc) and I have a few questions.

My biggest one is a problem with my car dying. It used to only happen sometimes when the engine was cold and I'd start it and back out without giving much gas (it would die as soon as I started turning the wheel). But this time it happened when I pulled away from a red light and turned. I coasted into the closest parking lot and started it again. The car would start fine, and then whenever I put it in drive and turned the wheel it would die, but only when I turned the wheel. At first I thought it was something with the power steering, but there are a few variables:

I had just been on like a 30ish mile highway trip. The car had three people, a guitar and an amp in it. It was the first really hot day in a while.

The thing is, we went back and put some gas in it and got it home and it hasn't done it since. It had been sitting for a day and I wish I would've tried to recreate it before I put more gas in because it had like 1/4 of a tank according to the gauge when it was dying. What do you guys think about this? Is it something to do with the power steering pump, the idle air control sensor, or something else? Could being low on gas cause something like this to happen? (my gas gauge floats so who knows)

My second biggest problem is LAUGHABLE gas mileage. I have the 3.1L V6 and I usually get about 12mpg average. I know that I should be getting way more than this. The other thing is that my gas mileage is MUCH worse on the highway. I don't use the AC or anything, seeing as it'd probably drop me down to like 10mpg. What are some things that could be the cause of this? I've recently replaced all the tires, the alternator/serpentine belt, the fuel pump, the brakes, and all of the ignition coils. The air filter is brand new, I pulled a spark plug and it looked brand new. This was my grandparent's car before mine and my grandpa keeps his cars in good shape. Could this be the O2 sensor or a combination of a lot of things? It really makes me mad.

Thanks in advance for your help.

**machinegunsquid** · 05-10-2010

Something has to be really messed up for you to only be getting 12mpg... Does the car struggle to build RPM when you give it throttle?? Im thinking a clogged cat. could be killing your gas mileage, and if it's clogged bad enough, it could be causing the engine to die.

And for the engine dying, does it only happen if you turn the wheel?? I ask because I've driven some cars that the RPM's drop off when you turn the wheel past 1/4 turn or so, and if your car has some problems already, it would easily shut the engine off.

If you can, check the cat. and replace O2 sensors.

If you start the car, and let it sit at idle, does anything happen??

**thehollowaytape** · 05-10-2010

The only time it hesitates is at stop signs, or when I make quick stops like that.

Yeah it only happens when I turn the wheel. I can hear the RPMs going down when I'm idling and I turn the wheel. I wish this car had a tachometer.

Nothing happens when it's idling, it will idle just fine. Even after it was dying the other day, it would still start and idle.

How would I check the cat? Sorry, I'm new to some of this stuff. I was planning on changing the O2 sensors though, so I will do that ASAP.

**machinegunsquid** · 05-10-2010

The easy way to check the cat is to find an open stretch of road, and stomp on the gas, if the car feels really sluggish, and it just doesnt want to accelerate past about 3.5k RPM, it's clogged. Or, for a small price, you can have a shop pressure check it.

Are you noticing any misfires?? Or does the engine get really rough when it dies?

**thehollowaytape** · 05-10-2010

Alright, so I could just go to a shop and have it tested? I think I will do that.

It does get pretty rough when it dies, yes. I don't notice any misfires, but I don't really know how to tell either. It sounds normal to me.

**machinegunsquid** · 05-10-2010

Ok, a misfire is when a cylinder doesn't fire at the correct time, or at all. Typically its like a little popping, or a lack of noise. (you'll hear the engine drop off for a tiny second.) It'll sound like its stumbling.

A shop will pressure check it for you, and it shouldnt cost very much. If you can, stop by a parts store and make sure you arent pulling any SES codes (check engine.)

**thehollowaytape** · 05-11-2010

Okay well as far as I can tell there are no misfires. I will have it checked asap.

It did it again yesterday, also. When I was turning into a parking lot. I tried to rev it a little in neutral before I turned and it sputtered like crazy and then finally died. This was with almost a completely full tank of gas.

Does this sound like it might be the Idle Air Control Valve to anyone? It doesn't happen when I'm going down the road or anything, at least not yet. Where is the IAC valve located on the 3.1L MFI?

**thehollowaytape** · 05-13-2010

Sorry for the double post but I am needing some more assistance.

So, over the past few days I have noticed some things about my car. It keeps getting to around 220F when idling. So I checked today and the radiator fans are not coming on. Next thing is the belt tensioner is bouncing around and it looks like the belt is scraping paint off of something below it. Could this be my stalling problem? Next, I have a coolant leak and I'm not sure if it's coming off of the engine block or what, I'm attaching a picture of where it's located. I'd really appreciate it if someone could help me out.

Also, on the image, the arrows are just the general area it's coming from. It's back beside the air box it looks like, not the points I'm pointing to in the pic.