Running lean!

[turbohead2332]

My 93 3.4 is running lean. I don't mean a little bit of raw fuel smell, either. I mean it smells like straight gas. It happens when the car gets hot and I turn it off then try to crank it up later. It's like it wants to idle super low and just cut off. Kinda like it has an ubercam in it. I have to give it about 1/3 throttle to keep it running. I then quickly rev it up, put it in drive and drive off. It doesn't accelerate for crap. It takes about 30 seconds of driving then it smooths out. This whole time, I smell a VERY strong smell of raw gasoline. Even at idle I smell it. It's really strong. What's causing this? Even if I don't have this problem, I can crank it up and it still smells like it's running lean some, but not near as bad.

[Ballee]

Re: Running lean!

lean would be mean less gas......i guess u r trying to say u r running rich...if this is the case than go for ur O2 sensors....if they r stock than change them..but see the plugs....coils.....plug wires...b4 u jump for the O2 sensor

[turbohead2332]

Re: Running lean!

lean would be mean less gas......i guess u r trying to say u r running rich...if this is the case than go for ur O2 sensors....if they r stock than change them..but see the plugs....coils.....plug wires...b4 u jump for the O2 sensor

I thought running lean = more gas, less O2 and running rich = less gas, more O2. Ah well. Either way, you get it. I changed plugs and wires about less than 1k or so miles ago. I was thinking possibly O2 sensor.

[Ballee]

Re: Running lean!

how old are the sensors? they could be the culprit.....u need to buy 2 sensors and the socket to change them

[Guardiannknight]

Re: Running lean!

To much air and not enough fuel=Lean

To much fuel and not enough air=Rich

Right amount of both=Perfect running condition

That's how I look at it.. :D

[camaroman1181]

Re: Running lean!

as stated, lean is too little fuel, rich is too much fuel..

How's the air filter? do you have a vacuum leak? could be a map sensor as well.. O2 sensors arent too bad of an idea. Not too horrible to change on our cars, and since the 3.4 uses non self heating sensors, they aren't too expensive either..

[turbohead2332]

Re: Running lean!

sweet. The o2 sensor(s?) are old. Actually all of em are old. Also my dad got to poking around under the hood while it was idling. He pulled the plug out by the throttle body, replaced it, then pulled the one out on the intake tube, then replaced it, then pulled the one coming from, I think, the O2 sensor. None of them had any effect on the car at all. Ideas? Oh, and my dad is the one who said it was running lean. We were going to get some lunch when this happened. All I know there is that I smelled straight raw gasoline.

[camaroman1181]

Re: Running lean!

change teh O2 sensors. I've seen some service intervals list them as frequently as every 12000 miles for the non self heating sensors. If they have been in there for a long time, its time to change them, even if they arent the main source of your problem...

[Guardiannknight]

Re: Running lean!

sweet. The o2 sensor(s?) are old. Actually all of em are old. Also my dad got to poking around under the hood while it was idling. He pulled the plug out by the throttle body, replaced it, then pulled the one out on the intake tube, then replaced it, then pulled the one coming from, I think, the O2 sensor. None of them had any effect on the car at all. Ideas? Oh, and my dad is the one who said it was running lean. We were going to get some lunch when this happened. All I know there is that I smelled straight raw gasoline.

The O2 sensors are located on the exhaust manifolds(or headers if you have headers), the O2 is probably attached before the Y-pipe begins. I'm also guessing the 3.4 probably also has a O2 after the CAT like the 3.8.

[Ballee]

Re: Running lean!

nah there r only 2 in the manifold........and they r easy to change ......just warm up the car ..it will make em free

[Guardiannknight]

Re: Running lean!

Yeah, wasn't for certain on the 3.4, about the after CAT one

[turbohead2332]

Re: Running lean!

sweet guys. Thanks. But like I said about the other 2...What does this mean since they didn't affect the idling at all?

[Guardiannknight]

Re: Running lean!

Other two?? Do you mean the sensor on the throttle body and the sensor in the intake?? I cannot right off think of what the names of this two sensors are, but there not the O2 sensors the members on here are talking about(at least I don't think they are). The air intake sensor is called, IAT sensor, it should detect the temperature of the air coming into the engine, now the one on the throttle body... I'm not certain about, since I don't know the setup of the 3.4. I would say it is a throttle sensor, but unlike my 3.8 yours does not have electronic throttle. But, it may be a throttle sensor, letting the computer know what throttle position is, so it can match up to the fuel/air tables. I could be wrong, but that is my guess on the sensor your talking about. Or, just thought of it, the one on your throttle body is probably the MAF(Mass Air Flow sensor). But, that sensor should be inside your throttle body, to detect, well, the amount of air coming into the engine. Like I said before, I don't know the setup of the 3.4, so I'm just guessing by what my 3.8 has.

The O2's are on your exhaust manifolds, right before the Y-pipe, and since you have a 3.4 you don't have one after the CAT as I just found out :)

The IAT probably won't effect your idle, now your MAF or if you do have a throttle sensor, those two could effect your idle, if they where bad, but if your going for your O2's, those are on your exhaust manifold, and yeap, can effect idle. Also, how many miles does that car have on it, and when was the last time the O2's and CAT was replaced?

[Guardiannknight]

Re: Running lean!

Also, so your saying your car runs fine when it's cold or when you first start it? And only does this when you let your car get to running temp, shut it off, and try to restart it? If so, yeah it does sound like a O2 sensor problem.

[turbohead2332]

Re: Running lean!

I know those aren't o2 sensors. I know where those are. It has 177.4k miles on it. I have no idea when they were replaced. Prolly way too long ago. When I did my spark plugs, I showed them to my dad who estimated they'd been in there near 100k miles. So I think the o2 sensors have need of changing. It's not when my car gets to running temp, it's when it's warm outside, say 80 or so or higher and I drive it for say 20 minutes, shut it off, get back in about 30 min later and it does that. The gas smell is strong enough to burn the nostrils.