Dear Ray and Tom my van is using way too much gas.I can smell gas at tail pipe and can feel the express pressure when it explodes in exhaust pipe.I changed plugs,wires,distributor cap and rotor and still exactly the same thing .It also floods out easy if i dont keep my foot on gas pedal at a stop.I been told by people that it could be one or more sensor but is there a way to tell if one is bad or what .Im a poor working man and cant afford to throw 100 dollar bills at it. If you could narrow down what sensor(s) I should look at where they are located I would greatly appreciate the help
First off…This is NOT a forum for Tom and Ray. Just other car enthusiasts…some are mechanics…some just like cars.
What year is your truck???
I’m assuming that this is fuel-injected. It sounds like it’s flooding. Too much gas and not all of it is getting burned up when existing the exhaust. This is NOT a good situation. First it can destroy the catalytic converter…and second it can dilute the engine oil.
Knowing the model year will help determine what the cause could be.
Is the van getting up to normal operating temperature? (dash temp gauge reading normally? heat ok?)
Ditto to Mike’s post. The truck’s mileage never hurts to know too.
My wild guess is that you either have a leaky injector or a cylinder not firing. It needs lookin’ at.
The problem might be with a leaking fuel pressure regulator. The fuel pressure regulator is usually located somewhere on one of the fuel rails. It’s a small canister with a single vacuum hose attached. Locate the fuel pressure regulator and remove the vacuum hose from the fuel pressure regulator. If gasoline leaks out of this vacuum connection the fuel pressure regulator is defective and requires replacing.
Tester
Don’t forget the O2 sensors…if they are bad…then the vehicle will default to run the engine as RICH as it possibly can by default…since it cannot lean itself out any longer without O2 inputs…this will make you CHUG-A-LUG FUEL…you will smell raw fuel from the tailpipe also…BIG BIG fuel waster…
Also what on earth are you talking about when you said “I can smell gas at tail pipe and can feel the express pressure when it explodes in exhaust pipe”
For Gods sake I certainly hope that there is no EXPLODING of any sort ANYWHERE near your vehicle… I think you are trying to describe something else here and are lacking the vocab… Help me out on that one.
Blackbird
Gives whole new meaning to the term “secondary combustion”.
Hey, the cat converter can reach over 800F. A candle flame is, what, only 750F? A bunch of free hydrocarbon molecules surrounded by oxygen hits that and POP!
the van is a 2002 chevy express .Yes i can smell gas from tailpipe and can feel excess pressure when it pops .The only way to keep it running at a stop is with foot on brake and gas
the van does get up to normal temp
where do i find these O2 sensors
The oxygen sensors are located in the exhaust stream(s), just fore and aft of the primary catalytic converter.
With respect, allow me to suggest that your lack of knowing where to look for the oxygen sensors, combined with your not recognizing that the suggestion is only one of many possibilities, implys that you may intend to replace parts until the problem disappears. If this is true, you may just save a ton of money and prevent a more serious problem, by just taking the vehicle to a reputable local shop.
+1 on what mountainbike said.
Checking the fuel pressure regulator is a no brainer though. (Not so for O2 sensors).
As I stated in my first post I am a POOR working man.If and when I can afford a reputable shop That is probably where I will end up taking it.Until then I am trying to save myself some money by working on it myself.My mechanical knowelge is mostly limited to muscle cars before computers and sensors.I really appreciate all the help you have been. From looking at diagrams for this van I see the fuel pressure regulator it under the plastic intake plenum and there is no vacumn house connected to it but it does have a tube that ypu would normaly see a hose connected to .
As I stated in my first post I am a POOR working man.If and when I can afford a reputable shop That is probably where I will end up taking it.Until then I am trying to save myself some money by working on it myself.
What MB has pointed out…is you lack of knowledge IS COSTING YOU MONEY. Taking it to a reputable mechanic NOW is going to SAVE you money.
If you’re saying that there is no vacuum line attached to your pressure regulator where one should be then your fuel pressure is probably too high.
Get that figured out. Sometimes Autozone’s free online repair info can be very helpful.
I’d figure out that fuel pressure regulator thing first. No vacuum line means a direct air leak into the intake manifold. With vacuum line in place then it’s easy enough to check the regulator as far as a leaking diaphragm.