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1990 Jeep Cherokee pioneer dies when given quick throttle?

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Old 10-13-2019, 11:20 PM
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Default 1990 Jeep Cherokee pioneer dies when given quick throttle?

I am at my whits end with this and Google searches of every combination of words I can think of lead me to the same dead ends.

My jeep will start okay at the beginning of a day.
Flip a coin and it'll work seemingly fine, if a little underpowered? (seems to take a lot of throttle to go only 25)

The other half of the time, if I press the gas (rather normally, like you would taking an unprotected left turn) it will kill the engine. It just starts to shut down. If I let off the gas quick it will rumble back up.
If I very carefully creep the throttle up it will drive okay. Letting off the gas quickly doesn't kill lthe car. However, it will sound funky, like the idle will go very low, then back a little high, then steady out.
My Model does not have a tachometer.

It will refuse to start for at least 30 minutes if I do kill the engine after this.

After Researching My issue extensively I have done the following:

- replaced the tps and tuned it to spec (. 83 volts of the reference a-b on the b-c wires in my automatic) my tps will not read in acc or on position I have to start the car.
- replaced the iac
- replaced the fuel filter
-checked the voltage to the fuel pump

- read the fuel pressure: reads ~32psi at idle, but it goes up to about 35 slowly when given throttle (this is when the car isn't stalling out on me)

- replaced air filter
- checked for proper spark on the plugs
- straight piped the car by removing the cat and muffler (they are definitely clogged, but on/off seems to make little difference)

Any guidance on my issue is much appreciated.

I will try and take a video of the engine dying as soon as I can.
Old 10-14-2019, 07:43 AM
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Year: 1990
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Fuel pressure should be 31 at idle and go to 39 when you pull the vacuum line off the pressure regulator.

Have you visited my website and completed at the very least Tips 1,3,4, and 5?
Old 10-14-2019, 04:06 PM
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Thank you for this. I will go through your listed steps throughout this week.
Old 10-14-2019, 04:55 PM
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Originally Posted by CJ G
Thank you for this. I will go through your listed steps throughout this week.

Any questions, ,post them up.
Old 10-14-2019, 05:16 PM
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Year: 1989
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What was your voltage to the fuel pump, btw? If you still have it, try bypassing the fuel pump ballast resistor on the front drivers fender to get full voltage to the fuel pump.
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