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This car frequently hesitates badly and sometimes stalls out when trying to pull out from a red light. Otherwise it seems to run fine. When in park, there is no problem revving the engine, only after I stop for 60 seconds or so and idle in gear. New filters (all) new plugs, cap, rotor. It seems to be either starving for fuel or flooding out. I had Bosch Plat plugs, but changed back to OEM plugs and the problem went away for about a week. I'm guessing plug wires, timing, or fuel pump, but don't know. The car runs fine once she gets over the stumble. No emissions light appears. Any help you could provide would be appreciated
Answer -
Hesitation on most electronic vehicles is usually caused by an intermittent fault of the THROTTLE POSITIONING SENSOR (TPS). In a lot of cases it will NOT turn ON the SERVICE light on the dash.
What work has been performed of anykind prior to this problem ?.
onlineautohelp
The only work prior was new plugs, cap, rotor, filters (fuel, air, oil) and a coolant flush and water pump replacement. The problem arose about a month later. Then I went to new OEM plugs and it went away for a week. (coincidence?) I replaced the plug wires and checked fuel pressure last night. Problem persists. I plan to check the timing next as it has not been done. (Car bought in August)The car burns no oil and normally gets 30+ mpg. Have not checked mpg's lately.
Can the TPS be cleaned or adjusted or is it simply to be replaced?
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The TPS must be replaced. It is a common fault that causes hesitation.
thomas
autohelp
I replaced the TPS and verified timing at 5 BTDC. The problem persists, and now the engine is slow to return to idle. When put in gear, the engine surges. I have 5 volts going into the TPS, 0.75 volts out at idle and 4 volts out at wide open. The TPS mounting allows for adjustment, so I mounted it at the same position as the original. Are the outputs correct?
What would be the next logical step to take or part to check? Still no SES light or codes, but the light does activate if I unplug components.
Answer0.75 volts at idle is to high. Is there any way for you to e-mail me pictures of your engine compartment so I can visually see what componenta you have on it.
At BASE IDLE SPEED the TPS setting is around 0.20 to 0.30. I don't have a metro book so you will have to try different TPS settings unless you can find a book that gives you the exact voltage setting.
Look around the engine compartment for loose, worn or cracked vacuum lines. Especially look at the MAP (Manifold Absolute Pressure) sensor rubber line from the sensor to the intake.
Send me several pictures of the engine compartment to my personal e-mail address being:
meperganfortis@msn.com
Thomas
