Why does the idle speed decrease on an 2001 intrepid after it is warmed up causing the oil light to flicker while idleing?

Answer 1

The idle speed decreases to a set point as the engine warms up naturally. The engine when cold needs more fuel than air to stay idling. As the engine temp rises it tells the computer to cut back on the fuel and when it does it lowers the idle rpms. It is a natural thing. If your oil light is out when the engine is cold and idling, and then comes on when the engine becomes warm, you may have an engine oil problem. First check the level of engine oil aftre the engine has been sitting for more than 15 mins. If it needs oil, then add it. You check it using the dipstick, pulling it out, wiping it off and reinserting it and checking the level. If you have enough oil, then you have an oiling problem as far as pressure. The warmer the engine gets, the thinner the oil gets. Thinner oil gives you lower oil pressure at idle. Your oil pump may also be going out, or you may need an overhaul on the engine at the crank. The tolerances where the oil flows inside the engine get larger as the engine ages with miles and uses. This is why it is important to use quality oil but most of all change it as recommended with the filter. You may want to try a thicker oil as a band aid to help the oil pressure but this is only a temporary fix. Eventually the engine will need an overhaul if the bearing surfaces wear out. If you are using an oil with a weight of 5-20, try a 10-30. If you are using a 10-30 try a 10-40. I wouldn't suggest a 20-50 oil since this is a very heavy oil viscosity that is not primary used in todays engines. It is mostly a racing oil. So check the engine oil level, try a little heavier oil weight, start saving for an overhaul. Low oil pressure is a sign an engine needs help beit a new oil pump, a new oil pressure sending unit (the sending unit could be At Fault sending you a false oil pressure warning) and alas.....an overhaul. If the engone idle is falling to lower than normal rpms causing the oil light to ome on, then your tps, throttle position sensor may be going bad. It may be telling the computer the car is idling at 800 when in reality it is idling at 500 and throwing the engine oil light to come on. Determine if it is an oil pressure problem, a gauge problem, a tps sensor problem While the engine is cold the idle speed is increased to keep it from stalling. If the oil light comes on once the engine warms up, you probably have worn main/rod bearings. Switch to a heavier grade oil. If you're using 5W15, switch to 10W30 or even 15W50. Use the lowest number oil possible to get the light to stay out. Typically, low oil pressure is caused by worn bearings, but of course there can be other causes for what you're seeing, such as a faulty sensor or worn oil pump, but the problem is ALMOST ALWAYS worn bearings. On the 2.7L DCX engines (esp. 1998-2004 models), when at normal operating temperature the oil light flickers because of excess PSI on the oil pressure sensor. The oil pressure sending unit is right below the exhaust manifold, and at normal op. temp. the heat causes excess pressure behind the switch giving a false reading. The TSB for this issue is to install the vent wire accessory onto the pressure sending unit's spare plug hole to relieve the pressure. You should have your oil pressure checked before hand though to rule out a blocked oil pump pick up tube or worse problems. Chrysler recommends 5w30 synthetic for regular changes at 2500mi.