QuestionQUESTION: My friend has a 2002 Pt Cruiser, When he goes on trips say over 100 miles the vehicles tends to run hot. When it starts running hot if he revs the engine the temp hand will actually fall back to a normal range. He has flushed the radiator and changed the thermostat. What is he missing? Could it be the water pump? Also now after it has gotten hot (Never to the red level but close) it takes a couple of tries to start the engine?
ANSWER: Hi Jeff,
Are the cooling fan coming 'on' soon enough? If not then that fact plus the difficult hot start would make me wonder if the coolant temperature sensor is inaccurate. It tells the computer when to turn on the fan, and also what air/fuel mixture is needed to start the engine. The resistance across its two contacts should read about 700-1,000 ohm at normal operating temperature. If it reads higher than that, it would explain the problem in all likelihood. (When cold the reading would be about 7,000 ohms). On both of the possible engines the ect sensor is located at the thermostat housing. (Tell me which engine if in doubt at to location of the housing). Lift the tab on the connector, then pull off the connector to get to the contacts to measure the resistance of the sensor. There might be a fault code that says whether there is a problem with the sensor. Turn the igntion key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see if the mileage reading changes to show any four-digit numbmers preceded by a P. Let me know the numbers and we'll go from there.
Another possibility is that the air fins of the radiator are clogged so put a light behind the radiator and look through the grille to see if the light is visible over the entire area of the radiator. If not, clean out dirt and debris with a hose and water. I doubt it is the waterpump.
Roland
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QUESTION: I did the ignition like you said and got the following codes....1684, 0401, 0442, 0455. (All preceded by P)
AnswerHi Jeff,
The 1684 just says that sometime in the past 50 ignition key cycles the battery was disconnected. If not so, then check the battery clamps
The 0401 says the egr valve is not functioning properly. It is located at the rear of the engine, lower then the power distribution box (remove air cleaner lid and its sensor wires and makeup air hose for access). It could simply be that the valve stem is sticking due to build up of exhaust crud. Examine the valve for a rod (hidden inside of a flange located between the round top of the valve (with vacuum hose) and the valve body proper. If you see a rod it should have a slot into which a screwdriver can be inserted to move the stem back and forth, so test the movement. If not, then the valve should be removed and cleaned which is a multi-step process which I can send you xerox copies of the pages showing how to do that). If the rod is found and moves but seems to not close tightly by spring-action then spray some WD-40 on the stem where it enters the valve body and work it back and forth to free it up.
The other two codes say there is a leak in the gasoline vapor recovery system. That system connects from the gas tank where there is a vapor pump at one corner, a hose from there to the purge solenoid (located under the vehicle near the power steering pump) and hose to the intake manifold from there. Probably the first thing to do is check all the hoses at the fuel tank/vapor pump and hose to the solenoid and hose to the manifold to see if you find a loose fitting or damaged hose.
Roland
PS Thanks for the rating and nomination.
