Hard start when warm, runs fine when cold
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Hard start when warm, runs fine when cold So i have got the car back together with it relating to an intake leak after doing the egr delete process. Now i'm have issues with the car running like crap and popping and crackling and then not starting correctly when i shut it off or not starting at all until it cools off for a bit. Seems to run fine for 30-45 minutes of driving it, then gets to temp and goes completely downhill. Replaced opti, icm, coil, fuel pump, but still haven't got to tune it or to the new plugs and wires. Don't know if either of these could be related? Can't figure out why it's doing this. Also, wants to die at light throttle after it warms up and seems like it has some type of drag or bog when driving. Like i said, runs fine when cool until driving for awhile. Any suggestions would be greatly appreciated on this. Thanks!
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From: CenTex
When it warms up and dies, try to restart it while holding the gas pedal to the floor, or unplugging the temp sensor in the water pump. If it starts, you'll need to replace the temp sensor, and the plugs because they'll be fuel fouled.
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yes. i drive it around for a little while and then it starts acting up. Yesterday is when i had drove around and shut it off several times etc and i had problems starting it.
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Update: Now when it starts to run weird when it warms up, i ABS INOP light kicks on and the car starts missing and running like crap. don't know if that's an indication or not but that's when it starts
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I would try unplugging the O2 sensors like SS RRR suggested. The o2 sensors only play a factor in Closed Loop "when the car is up to temp", so if your saying the car is fine in Open Loop "cold, not to operating temp" try unplugging the o2 sensors. bad o2 sensors can cause false readings to the PCM, which can cause crazy fuel ratios in Closed Loop which lead to misfires from dumping too much fuel and soaking the spark plugs.
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sounds like a voltage issue to me. Everything has a required voltage to run properly and will act up if it's not where it needs to be.
Kyle's recommendation would be the first point I would start. Get a scanner and see what the sensors are reading. I have a feeling it is either a coolant temp sensor or air intake sensor and now your plugs are fouled causing the miss. It could be a number of things but the easiest way to narrow it down would be to scan the car and see what the sensors are reading (you can also check the voltage as well).
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Update: Car is now not wanting to start first time when cold like it has before. Like stated before, starting with the gas pedal to the floor works everytime now even when it's cold or hot. Starts up first time every time with the pedal mashed and turning it over.
The computer is dumping fuel through the injectors. When you floor the car it shuts off the injectors (fuel) and that is why it is starting up. I would guess Coolant temp or Intake air temp or both. You really need to scan the car to see what the pcm is reading from the sensors. You can trick the pcm by putting resistors in the coolant temp plug to see if it helps. If the car is cold put a 3000 ohm resistor (this will be around 80 degree coolant temp reading) in the coolant temp plug (jump the resistor in the plug) and see if it helps with cold start up. If it does, shut off the car and replace the coolant temp sensor (the one in the water pump). If it doesn't help, unplug the intake air temp sensor and try the same thing with the same resistor.