i got a 88 olds and it is running rich and i have done everything you can mention but i was wondering if a fuel pump regulator can do that?the things i did was:new cat,new muffler,new throttle position sensor new cam sensor,pcv valve,egr valve new plugs,new plug wires,new air filter,i cleaned out the throttle body,and iam running out of things to try,so i was wondering if a fuel pump regulator can do it.i have 41 lbs. on my fuel pump.any help will be appreciated.thanks.
2006-09-21 16:12:59 · 11 answers · asked by Anonymous in Cars & Transportation ➔ Maintenance & Repairs
If it surges on occasion it maybe the fuel pump regulator but i don't see how it could make the mixture rich. I would get the computer diagnosis and see what is going on for sure before you swap out anymore parts
2006-09-21 16:29:05 · answer #1 · answered by Johnny 2 · 1⤊ 1⤋
when an Oxygen sensor fails it most offen tell the ECM that It's running lean. In an effort to correct this percieved problem the ECM will usually add fuel to try to get a signal out of the sensor ( 0.0v is full lean ) (0.7 - 0.99 is rich ). If the sensor really is bad nothing will happen so the ECM will make a desparate attempt to reach a stoiciometric ratio by driving the fuel trim full rich. Since oxygen sensors produce their own voltage you can disconnect the connector and using a digital volt meter probe the wire with the engine on. If you have between 0.1v and 1.01v (It should be switching between high and low) the sensor is probably OK. If it just sits at 0.00v and does nothing replace it.
ALSO REMEMBER: O2s only work when they are very HOT. So heat up the eng before testing but be careful not to burn yourself.
Also a coolant temp sensor that constantly sends a cold signal to the PCM will have your car running in cold eng. enrichment mode and will also waste alot of fuel.
41 PSI is very good fuel pressure for your car and no problem is indicated, look somewhere else.
2006-09-21 17:03:33 · answer #2 · answered by Anonymous · 1⤊ 0⤋
You know the O2 sensor controls fuel to the engine. I would have checked this little gem first, before I replaced all that other stuff. The O2 sensor reading tells the ECM how much fuel to deliver to the engine. If it is reading rich, then maybe another trip to the parts store is in order to pick up an O2 sensor.
2006-09-21 16:33:28 · answer #3 · answered by yugie29 6 · 2⤊ 0⤋
There are a whole bunch of sensors that you can check... if you already checked out the throttle & cam sensors, try the oxy sensors or the MAS... if those are good then it just could be your ECU acting up... Comp problems on the older gms are a biznatch... but good luck man. Try gettin a diag if u havent already, but i imagine u have becuase u sound like u know what u r doing, so keep pluggin away; you'll get it.
2006-09-21 16:30:31 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Spec for that car is < 15 psi. Regulator is most certainly questionable, but also check the return line and make sure it isn't kinked or restricted in any way.
Another thing that will make it run rich is a defective coolant temperature sensor (for the ECM, not the dash gauge).
If it is within spec, check to see that the thermostat is not stuck open, or missing.
The ECM needs to see an engine warmed to at least 175 deg. to maintain closed loop.
If your oxygen sensor is stuck "lean" it will drive the ECM to add fuel.
But above all, get that pressure down!!
Good Luck
2006-09-21 17:23:34 · answer #5 · answered by Ironhand 6 · 1⤊ 1⤋
YUGIE29 is right.The o2 sensors tell your computer how much fuel to deliver. You may have more than on on your car. And they are starting to get e little pricey too since the gas crunch started. But that is probably where your problem is. If it is you'll kick yourself because you installed all that other stuff and wasted your money
2006-09-25 12:52:58 · answer #6 · answered by whtsthislif4 5 · 1⤊ 0⤋
Put a fuel pressure gage on it and see what your pressure drop is. Just turn the key to run, don't start the engine, and watch the gage. You may have leaking injectors. You didn't say what engine you have, or the year. If it is a 3.8, you should state what generation it is. If you give us this info, one of us will be able to help you.
2006-09-21 17:05:57 · answer #7 · answered by B H 3 · 0⤊ 0⤋
well if it is running rich, you might want to check your choke. your timmimg might be off some. check your timming on the indicator on the front of your car under the hood and keep the engine running while you adjust the choke. you could try a fuel pump regulator. that might do something, but if nothing else works then I don't know what to say...i'm just a girl who likes motors.
2006-09-21 16:22:20 · answer #8 · answered by kaleo 3 · 0⤊ 2⤋
to tell you the truth i believe you have approached this problem from the wrong direction first thing you should do is open the hood locate the radiator cap remove it with your left hand while dialling a tow truck with right hand once car is removed from driveway slide new car in open hood and place radiator cap on radiator close hood problem solved
2006-09-21 16:26:06 · answer #9 · answered by alledgedflatlander 3 · 0⤊ 2⤋
damn right it will so will a bad o2 sensor
2006-09-21 16:41:20 · answer #10 · answered by natallbad 4 · 0⤊ 0⤋