1988 phazer after driving for 30-40 minutes it starts missing bad and slows to about 15-20 mph keep driving like that for 5 minutes then it takes off for about a minute then rigth back to missing but leave sit for an hour and runs great for 30 minutes dont know what it is

Playing out a drive cycle subsequent to supplanting an O2 sensor and exhaust system assists the vehicle's PC framework with relearning and recalibrate. Here are the general advances you can follow for a 2004 Pontiac Sunfire:

Cold Beginning: Guarantee the motor is cold. Turn over the motor and let it inactive for 2 minutes.

Inactive: Put the vehicle in "Drive" and inactive for 2 minutes with the A/C on (if prepared).

Speed up: Advance rapidly to 55 mph at half choke and keep up with speed for 10 minutes.

Decelerate: Slowly decelerate to 20 mph without utilizing the brake pedal.

Stop: Reach a stand-still and inactive in "Drive" for 2 minutes.

Speed up Once more: Advance quickly to 55 mph at half choke and keep up with speed for 5 minutes.

Stop Once more: Reach a stand-still and inactive in "Drive" for 2 minutes.

City Driving: Drive at 25 mph for 5 minutes, then, at that point, at 45 mph for 5 minutes, making a point to differ speed and burden.

Pause and Inactive: Reach a stand-still and inactive in "Drive" for 2 minutes.

These means ought to help the vehicle's PC framework relearn and change in accordance with the new parts. Remember that particular drive cycle strategies might shift, so it's consistently smart to counsel the vehicle's manual or contact a certified specialist for the most reliable data

1. The testing has to start with the vehicle under 122 degrees F. Start the engine and idle for 2.5 minutes in Drive (auto) Neutral (MAN) A/C and rear defogger ON.

2. A/C OFF, accelerate to 55 MPH at 1/2 throttle and then 3 minutes of steady state cruise at 55 MPH.

3. Clutch engaged (MAN) no braking decelerate to 20 MPH.

4. Accelerate to 55-60 MPH at 3/4 throttle and 5 minutes of steady state cruise at 55-60 MPH.

5. Decelerate, no braking to end the drive cycle.

In some cases the Powertrain Control Module (PCM) will go into a logic lock not letting the readiness monitors run. Removing the battery cables and touching the two together will normally take care of the logic lock condition.

Have the crank position sensor checked. This sounds very familiar.

1.let car sit overnight. 2. Start engine, put A/C on high, let it idle for 20-25 minutes, 2, then drive car uninterrupted for 60mph for 10 minutes, 3. slow down to 25 mph for 4 minutes, come to a complete stop with foot on brake let it idle for 2 minutes, 4. drive again at 30 mph for 8 minutes, come to a complete stop let it idle with foot on brake for 3 minutes. 4. Drive at 40 mph (turn off overdrive) for 6 minutes. 5. Drive at 20mph for 3 minutes at a time, each time coming to a complete stop with foot on brake for 2 minutes. Do this 4 times. Let the car cool overnight and repeat entire process. Then check status of systems with a code scanner.

If you need further help, reach me via phone at https://www.6ya.com/expert/daniel_4061c3d97c12c4c7

May be a bad coil. It will only fail when hot.

Here is the OBD2 emission system drive cycle test procedure.
Engine coolant temp must be below 70c (158f) before starting the engine for either the first or second trip
The fuel level should be less than 1/2 full
First trip:
Start engine, idle for at least 1.5 minutes
Drive 3 minutes, hold b/f schdl: 1.5-2.0 msec, selector lever "3rd" eng rpm 1,800-2,000 A/C switch:ON Hold the recommended b/f schdl range. Allow road speed to vary as necessary.
Drive at 55-65 mph for 1.5 min b/f schdl 2.0-3.2 msec, selector lever "5th" Engine rpm 2,200-3,000
IGN "off" for at least 10 seconds (not more than 5 min)
Dive at 50-60 mph for 3 minutes Selector lever "4th" keep engine speed above 3,000 rpm Allow speed to vary if necessary. Do not decelerate for more than 3 consecutive seconds. A/C switch ON.
Drive at a steady state cruise of 53-58mhp b/f schdl more than 1.8 msec selector lever "5th" eng rpm 2,400-2,600
Downshift to "4th" and decel more than 5 seconds without breaking, then idle for 1 minute.
Drive two minutes b/f schdl less than 2.0 msec Accelerate to 41 mph, decelerate to 34 mph, accelerate to 41mph. Do not completely release the accelerator. A/C switch off.
Idle 1 minute in park or neutral
Drive two minutes Steady state cruise at 31-44 mph. Selector lever "4th" A/C switch OFF. Hold the accelerator pedal as steady as possible. Allow speed to change if necessary.
End of first trip. Turn the key off the begin the second trip.
Second trip:
Start engine, idle for at least 1.5 minutes
Drive 3 minutes, hold b/f schdl: 1.5-2.0 msec, selector lever "3rd" eng rpm 1,800-2,000 A/C switch:ON Hold the recommended b/f schdl range. Allow road speed to vary as necessary.
Drive at 55-65 mph for 1.5 min b/f schdl 2.0-3.2 msec, selector lever "5th" Engine rpm 2,200-3,000
IGN "off" add four gallons of fuel
Dive at 50-60 mph for 3 minutes Selector lever "4th" keep engine speed above 3,000 rpm Allow speed to vary if necessary. Do not decelerate for more than 3 consecutive seconds. A/C switch ON.
Drive at a steady state cruise of 53-58mhp b/f schdl more than 1.8 msec selector lever "5th" eng rpm 2,400-2,600
Downshift to "4th" and decel more than 5 seconds without breaking, then idle for 1 minute.
Drive two minutes b/f schdl less than 2.0 msec Accelerate to 41 mph, decelerate to 34 mph, accelerate to 41mph. Do not completely release the accelerator. A/C switch off.
Idle 1 minute in park or neutral
Drive two minutes Steady state cruise at 31-44 mph. Selector lever "4th" A/C switch OFF. Hold the accelerator pedal as steady as possible. Allow speed to change if necessary. I especially like the part where they want you to add four gallons of fuel. Not three gallons, not five gallons, four gallons. Gotta love those Nissan engineers. ...and of course they state that if the trace is not followed exactly (i.e. you botch the acceleration/deceleration) you have to start all over again from scratch

takes a long time to run the rediness test since there are 6 different tests to complete...

PROCEDURE 1
EVAPORATIVE EMISSION SYSTEM LEAK MONITOR
Inspection Conditions
Engine coolant temperature: 30°C (75°F) or less (The engine is stopped before the test drive is started).
Atmospheric temperature: 5 - 30°C (41 - 113°F).
Condition of A/T: Selector lever D range.
Fuel remained in fuel tank: 30 - 50% is recommended.
Time required: 16 minutes or less after started the engine.
Drive cycle pattern: One trip monitor (from start to ignition switch to "LOCK" (OFF) position. Well be completed while traveling with the following drive cycle pattern.
Test Procedure
Engine: start.
Accelerate until the vehicle speed is 89 km/h (55 mph) or more.
While keeping the accelerator pedal opening degree constant, keep the vehicle speed at 89 km/h (55 mph) or more and travel for 16 minutes.
Return the vehicle to the shop, then turn the ignition switch to "LOCK" (OFF) position.

PROCEDURE 2
FUEL TRIM MONITOR
Drive Cycle Pattern
Inspection Conditions
Engine coolant temperature: 100°C (212°F) or less.
Atmospheric temperature: -10 - 60°C (14 - 140°F).
Condition of A/T: Selector lever D range.
Time required: 30 minutes or more.
Drive cycle pattern: One trip monitor (from start to ignition switch to "LOCK" (OFF) position). Will be completed while traveling with the following drive cycle pattern.
Test Procedure
Engine: start.
Accelerate until the vehicle speed is 89 km/h (55 mph) or more.
While keeping the accelerator pedal opening degree constant, keep the vehicle speed at 89 km/h (55 mph) or more and travel for 30 minutes.
Return the vehicle to the shop, then turn the ignition switch to "LOCK" (OFF) position

PROCEDURE 3
CATALYTIC CONVERTER MONITOR
Drive Cycle Pattern
Inspection Conditions
Atmospheric temperature: -10°C (14°F) or more.
Condition of A/T: Selector lever D range.
Engine coolant temperature: Not set.
Time required: 16 minutes or more.
Drive cycle pattern: One trip monitor (from start to ignition switch to "LOCK" (OFF) position). Will be completed while traveling with the following drive cycle pattern.
Test Procedure
Engine: start.
Accelerate until the vehicle speed is 89 km/h (55 mph) or more.
Travel for 300 seconds or more while keeping the vehicle speed at 89 km/h (55 mph) or more.
Decelerate until the vehicle speed is within 80 km/h (50 mph) or less.
While traveling at 56 - 80 km/h (35 - 50 mph) for 10 minutes or more, fully close the throttle at least once in 2 minutes and decelerate for 10 seconds or more.
Do not repeat deceleration too often.
Vehicle speed may go below 56 km/h (35 mph) after the deceleration.
Stopping and braking are permitted. (If stopped or drive at 56 km/h (35 mph) or less for more than 5 minutes the monitoring may be stopped. In this case please restart monitoring from the beginning.)
After completing the above deceleration, bring the vehicle speed back to 56 - 80 km/h (35 - 50 mph) and keep it in the range until starting the deceleration again.
Repeat the above deceleration at least 5 times.
Return the vehicle to the shop, then turn the ignition switch to "LOCK" (OFF) position

PROCEDURE 4
HEATED OXYGEN SENSOR MONITOR
Drive Cycle Pattern
Inspection Conditions
Engine coolant temperature: 100°C (212°F) or more.
Atmospheric temperature: -10°C - 60°C (14 - 140°F) or more.
Condition of A/T: Selector lever D range.
Time required: 16 minutes or more.
Drive cycle pattern: One trip monitor (from start to ignition switch to "LOCK" (OFF) position). Will be completed while traveling with the following drive cycle pattern.
Test Procedure
Engine: start.
Accelerate until the vehicle speed is 56 - 80 km/h (35 - 50 mph).
While keeping the accelerator pedal opening degree constant, keep the vehicle speed at 56 - 80 km/h (35 - 50 mph) and travel for 16 minutes or more.
Stopping and braking during this operation are permitted. Keep the accelerator opening degree constant for 1 minute or more after each acceleration.
Return the vehicle to the shop, then turn the ignition switch to "LOCK" (OFF) position

PROCEDURE 5
EXHAUST GAS RECIRCULATION (EGR) SYSTEM MONITOR
Drive Cycle Pattern
Inspection Conditions
Engine coolant temperature: 100°C (212°F) or less.
Atmospheric temperature: 5 - 60°C (41 - 140°F).
A/C switch: OFF.
Condition of A/T: Selector lever D range.
Time required: 16 minutes or more.
Drive cycle pattern: One trip monitor (from start to ignition switch to "LOCK" (OFF) position). Will be completed while traveling with the following drive cycle pattern.
Test Procedure
Engine: start.
Accelerate until the vehicle speed is 56 - 80 km/h (35 - 50 mph).
While traveling 16 minutes or more at 56 - 80 km/h (35 - 50 mph) with engine speed 2,000 r/min or above, fully close the throttle at decelerate for 5 seconds or more until the engine speed reaches 1,000 r/min or under.
Do not repeat deceleration too often.
Stopping and braking are permitted (Rapid deceleration and sharp steering are not permitted).
After completing the deceleration, bring the vehicle speed back to 56 - 80 km/h (35 - 50 mph) and keep it in the range until starting the deceleration again.
Repeat the above deceleration at least 8 times by fully closing the throttle valve.
Return the vehicle to the shop, then turn the ignition switch to "LOCK" (OFF) position

PROCEDURE 6
OTHER MONITOR (Main Components, Sensors & Switches, Wire Breakage & Short Circuit)
Drive Cycle Pattern
Inspection Conditions
Engine coolant temperature:
100°C (212°F) or less (Except engine coolant temperature sensor monitoring).
30°C (86°F) or less (Engine coolant temperature sensor monitoring).
Atmospheric temperature:
5°C (41°F) or more (Except engine coolant temperature sensor monitoring).
-10°C (14°F) or less (Engine coolant temperature sensor monitoring).
Condition of A/T: Selector lever D range.
Time required: 21 minutes or more.
Drive cycle pattern: One trip monitor (from start to ignition switch to "LOCK" (OFF) position). Will be completed while traveling with the following drive cycle pattern.
Test Procedure
Engine: start
Accelerate until the vehicle speed is 56 km/h (35 mph) or more.
While keeping the accelerator pedal opening degree constant, keep the vehicle speed at 56 km/h (35 mph) or more and travel for 16 minutes or more.
Return the vehicle to the shop.
After stopping the vehicle, continue idling for 5 minutes, and then turn the ignition switch to the "LOCK" (OFF) position. Moreover, the vehicle should be set to the following conditions for idling.
A/C switch: OFF
Lights and all accessories: OFF
Transmission: Neutral

Battery Charged ?

Battery leads tight and clean?

Checked Engine earth ?

If all OK then motor probably got some **** on the brush gear get sombody to help you, firmly apply hand brake.... ENSHURE IS IN NUTRAL OR PARK!
while they hold kek in crank position tap the starter motor with a hammer to free the crrap... that shuld do it!

Have A Great Day.......Bruce

ok..you must have more than one car???? you don't drive the 300 atall im guessing. #1 start car drive up the road and \back to your house. #2 let it idle till problem starts. #3 once it does start with the problem keep it alive with the gas pedal. #4 once your have it safely from dying in higher rpms "rev it" like a kid would, you know like if you were gonna race some one lol. be careful not to over rev or damage engine. you should do this for five minutes no longer than that. #5 let it idle for another 5 minutes. #6 repeat every day until problem with idling decipates. it took mine 3 300e like 3 days of this. if your not going to drive the car once you get the problem out of the way. turn the car on everyday and let it idle for 5 minutes atleast and take it for a short drive once a week. they get lonelly you know lol. later on you can just turn the car on every 2 -3 days and let it idle but still take it on a short drive atleast once a week

Have you checked your alternator?