Why does my 1999 jeep sport 4.0L die while driving?
It dies while driving specifically when letting off the gas like approaching a turn or stop sign, it starts great every time, will idle in park great, when you rev it in park it seems to take longer than needed for the engine to slow back to regular idle. We just bought it and have already replaced the battery and cables, rotor cap, spark plugs and wires. We knew it had this problem when we bought it and the guy claimed it was the vacuum lines. We repaired one vacuum line next to the battery connected to a canister and about 8 inches from the canister it connects to a tee with a larger vacuum line that was not connected to anything and we found a ball canister under the vehicle kinda behind the passenger headlight with line hanging there that we connected to the aforementioned larger vacuum line from the tee, there doesn't appear to be any cracks in the line as far as we can trace from the canisters to the engine and the firewall. The ac works but the heater does not. I have read and correct me if I'm wrong here but the crank position sensor can't be the problem if the vehicle starts. We really need to get it running by Monday any help will be greatly appreciated. The only other thing we can think to do is clean the throttle body and sensor inside which I will be doing tonight, and replace the in line fuel filter which will have to wait till tomorrow when i can buy one. It also has cruise control that didn't work before we fixed the vacuum lines and hasn't been tested since. I also read the heater having a short could somehow be affecting it but idk how to test for that. Again any help will be appreciated thank you. I will update later tonight or tomorrow.
Update, I removed the throttle body, took off all three sensors and cleaned all of it. Then we tested the throttle position sensor "tps" with a volt meter, the key in the on position but not started. We read that on the center pin you are supposed to read 200 milliamps and it actually read 766. Then using your hand open the throttle slowly and at wide open you are supposed to read less than 5 volts and we read 3.99, idk for sure but I assume that means the tps is good.
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