So I posted about some problems with my truck the other day (Which I found out was a TPS plug unplugged) And now im going to ask about another problem I am sure most of us have had but without all the right parts and such and not wanting to spend a lot to replace everything I would like to see what I could do to fix/find a source for the problem.

So my S-10 a 95 4.3 auto has been running “Super Rich” for a while now The truck was my step dads before it was mine and it has 204,XXX + miles on it and im getting about 10 MPG city I recently cleaned out the TB and such and now I am wanting to fix my rough idle problem.

I have done some research and I can smell the gas after a few minutes of running idle and I think my rough idle is from running RICH so question is what could be causing this and what is a easy way to pinpoint the problem.

I read the other day that at least 2 people with this year and model have had problems with jumping the truck causing damage to the computer in which it’s telling the injectors the wrong information and causes them to run rich without tripping any sensors. Now I hope that not it but one of the guys said they unplugged one injector and the truck ran at idle fine I have not given this a try but I don’t know what that will help any than just knowing .

So what other things can I look at and visually tell what’s wrong because like I said I have none of the computers and I don’t think my OBDII port is working.

 

Still looking for some answers here I may have made the post to long

So let’s see things that could cause the truck to drive rich I would say electrical or a bad injector. I mean if it was a clogged fuel line it should be lean and unless the pump was overworking it shouldn’t be pumping to much gas into the engine so what should I look at and how?

I can check the fuel pleasure but think it’s pointless and I’m not even sure which sensors to be checking please anyone some advice I’m waiting way to much gas and this little 4.3 already eats that gasoline up so any suggestions or advice would be great.

 

It could also be an O2 sensor but shouldn’t that pull a code as well?
Also could it be the idle air control switch? I took it out and cleaned the airways out but didn’t replace it I did replace the gasket though I know you can check the switch but turning the car almost on and seeing if it springs in and out.

The truck is fine at start up but when at intersections and stop signs it seems to wobble could it be because the IAC is partly stuck and not springing open all the way? I am pretty sure the O2 sensor has been replaced not too long ago but I’m not positive. The truck will stay bogged down after leaving the intersections if I am on the pedal I get nothing I have to ease into it and still until about 1,200-1,500 RPMs I am still bogging down.

 

It could possibly be the temp sensor. This like the 02 sensor should throw a code.

 

i have seen where o2 sensors are bad without throwing codes. had 2 on my tahoe that were shot, but the heater circuit portion was still functioning so no codes came up. upon replacing them, the rig idled and ran way better, mileage improved. i only knew cause of live data from my scantool showed me that the signal from sensors was way out of wack.

 

Well ill check the O2 sensor shouldn’t be too difficult to replace and a lot cheaper than a computer or an injector at the moment.

And the truck is not throwing any codes and unfortunately I don’t have a sweet scanner lol if I did life would be so so much easier when working on cars.


Temp sensor humm which one? I mean there are a ton are you talking about the one that is in the block on the drier side? I have had that sensor go out on a 92 scottsdale without throwing a code just a check gauges light and my gauge light is on so.

 

typically there are 2 temp sensors. 1 in thermostat housing that feeds computer, the other is usually in the drivers side head which feeds the gauge. the one for computer will generally trip a code and may trip the check gauge light, the one for gauge will usually cause gauge to read funny and trip check gauges. i don't believe the gauge sensor would cause a check engine light tho.

 

I agree, it would be the one by the thermostat.

 

Here is a little update.

I got in the truck today (I usually only drive it 2 miles to work and back) and noticed now the check gauge light isn’t even on now. The only light that is on now is the ABS light yet the truck is still running rich. Going to work is pretty much all downhill and coming home is uphill (obviously) and I noticed that going up even gentle slopes is difficult and the hill in front of my house is a bit more steeper than others and it just kept bogging down then when I got to the top of the hill and parker I could instantly smell gas. So now my question is could this be a pump problem? And if so why would it be running rich I would think a bad pump would cause a lean ride.

Im so darn lost.

 

have you changed plugs wire etc. air filter fuel filter if not i would try changin those and see how things go cuz my fullsize had the same problem with the boggin down and that was a fuel filter and then it was runnin rich so that when i changed plug and air fiilter and that fixed my runnin rich problem and if that dont work i would look into changin your injecter cuz on the 95 4.3's they had alot of issues with the spyder injector goin out and those run 2-300 bux at autozone and come with a 1yr wrnty