When does it misfire? Cold Idle or after heating up. O2's won't come into effect until after it heats up.

What about Coolant temp sensor? It is in the Water pump. They can cause misfires if bad. Unplug it and both electric fans should turn on. At cold startup it calls for more fuel.

What about the opti vent harness? Tube that goes from opti to the TB intake boot. The little blue elbow part that plugs into the intake boot. It should have enough vacuum to hold a piece of paper to it while running.

 

It does it cold if Im takin it out of the garage and cruising around the nieghborhood. It does it when its warm when Im drivin on the freeway goin about 60mph and when on the sevrice roads goin about 40mph. I can hit it back in nuetral just to see if it keeps doing it, but at that point it stops. I replaced the coolant sensor that is on the water pump. I never tried the paper in the boot trick I will do that on my second break and will let you know what I came up with.

 

Well Smoov I did what you said and its not sucking nothin. What's the next step now?

 

Get that fixed soon or you will be replacing the opti again in short time.

 

I would replace the vent tube. For now you could get away with a rubber hose and no check valve for troubleshooting. Inspect the Opti for burns/melting. you will have to pull it apart again. Sucks...

 

Man that would suck. Can you tell me how to check the fuel pressure regulator?

 

Hope this helps.

Buy a Fuel pressure guage and it will hook up to the back of the fuel rails on top of the intake. It is suppose to be in @ 43-45 PSI (41-47 PSI really). 41 is lean and 47 is rich.

Read below from factory service manual for further details:

CIRCUIT DESCRIPTION
When the ignition switch is turned "ON," the Powertrain Control Module (PCM) will turn "ON" the in-tank fuel pump. It will remain "ON" as long as the engine is cranking or running, and the PCM is receiving reference pulses. If there are no reference pulses, the PCM will shut "OFF" the fuel pump within 2 seconds after ignition "ON" or engine stops.

Inside the fuel tank an electric fuel pump (within an integral reservoir), supplies fuel through an in-line filter to the fuel rail assembly. The pump is designed to provide fuel at a pressure above the regulated pressure needed by the injectors. A pressure regulator, attached to the fuel rail, keeps fuel available to the injectors at a regulated pressure. Unused fuel is returned to the fuel tank by a separate line.

CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.


1.Connect fuel pressure gage as shown in illustration. Wrap a shop towel around the fuel pressure connection to absorb any small amount of fuel leakage that may occur when installing the gage. With ignition "ON" and fuel pump running, pressure should be 284-325 kPa (41-47 psi). This pressure is controlled by spring pressure within the regulator assembly.
2.When the engine is idling, manifold pressure is low (high vacuum) and is applied to the pressure regulator diaphragm. Vacuum will offset spring pressure and result in lower fuel pressure. Fuel pressure at idle will vary somewhat depending on barometric pressure but, should be less than pressure noted in Step (1).
3.A system that does not hold pressure is caused by one of the following:
•
◦Leaking fuel pump check ball.
◦Leaking fuel pump flex pipe.
◦Leaking valve/seat within pressure regulator.
◦Leaking injector(s).
1.A leaking injector can best be determined by checking for a fouled or saturated spark plug(s). If a leaking injector can not be determined by a fouled or saturated spark plug, the following procedure should be used.
•
◦Remove fuel rail but leave fuel lines connected.
◦Lift fuel rail out just enough to leave injector nozzles in the ports.
CAUTION: To reduce the risk of fire and personal injury that may result from fuel spray on the engine, make sure fuel rail is positioned over injector ports and injector retaining clips are intact.


•Pressurize the fuel system and observe injector nozzles.
1.Fuel pressure that drops off during acceleration, cruise or hard cornering may cause a lean condition and result in a loss of power, surging or misfire. This condition can be diagnosed using a Tech 1 (or equivalent) scan tool. If the fuel system is very lean, one or both oxygen sensors will stop toggling and output voltage will drop below 300 mV. Also, injector pulse width will increase.
NOTE: </B>Make sure system is not operating at "Fuel-Cutoff" which may cause false readings on the scan tool.
1.Fuel pressure below 284 kPa (41 psi) may cause a lean condition and may set a DTC 44/64. Driveability conditions can include hard starting cold, hesitation, poor driveability, lack of power, surging or misfire.
2.Restricting the fuel return line causes fuel pressure to build above regulated pressure. With battery voltage applied to the pump "test" connector, pressure should rise above 325 kPa (47 psi) as the valve in the return line is partially closed.
NOTE: Do not allow pressure to exceed 414 kPa (60 psi) as damage to the regulator may result.


1.Fuel pressure above 325 kPa (47 psi) may cause a rich condition and may set a DTC 45/65. Driveability conditions can include hard starting (followed by black smoke) and a strong sulphur smell in the exhaust.
2.This test determines if the high fuel pressure is due to a restricted fuel return line or a faulty fuel pressure regulator.
3.The pressure regulator filter screen is designed to trap any contaminants introduced during engine assembly. If dirty, it can be removed with a small pick and discarded without potential harm to the regulator.

 

Have you pulled your plugs and looked for fouled plugs? Could be a bad injector as well.

 

Plugs are fine. My machanic says it might be a bad injection or fuel pressure regulator.

 

I pulled the plugs from passenger side of the car and it looks everyone of them look good.

 

Double check your firing order. Make sure all wires are straight, fully seated, and none are crossed.
Also you stated that it only does it when it is hot? Correct. 02s come into effect after they heat up. Also your coil could be culprit.

 

I checked the firing order, made sure my wires are locked in tight and far away from my headers. I even put clamps and lum around them to b safe. Yes it does it when the car is warmed up. Plugs are seated well.

 

If its not sucking from the opti does that mean I have to replace the whole thing are just another cap and motor?

 

I would do the whole unit. Your casing is probably cracked. Betcha when you pull it apart you will have some black spots/burning/melting inside.

 

Ok, I got to get that done.