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Trouble w/94 SOHC

My buddy bought a 1994 SL1 SOHC w/automatic transmission. At this time, it is undriveable. I will try to explain the symptoms as best as I can. Cold engine-When you start the engine, it runs a little rough. If you give it some gas it smoothes out. Once you let off the gas, it idles at about 1200-1300 RPMs. Nothing you can do will drop the RPMs. The cooling fans comes on as soon as you start the car. When you put the car in gear, the RPMs jump up to about 2500 and will slowly drop back to 1200 RPMs. After a few minutes, the cooling fan stops running.

Warm engine-The engine starts and runs at 1200 RPMs. Put the transmission in gear and it again raises the RPMs to about 2500. But now if you give it some throttle, the engine will sputter and many times it dies.

Now after that, the engine is very difficult to get fired up again! You have to give it a little bit of throttle while cranking the engine and after about 4-5 seconds, the engine runs.

My friend was told to replace the throttle body gasket, which he did. This did not fix the problem.

The one thing that really is odd is the operation of the cooling fan.

The fan comes on immediately after starting the engine, regardless of the engine temperature. It will cycle off after a few minutes regardless of the engine temperature!

Any ideas?!?!?!?!?!?!?

Thanks! Jim Smith

Reply to
Jim Smith
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Before resorting to guesses, consider reading the stored codes. Luckily with 1st gen cars, you can do it with a paperclip.

Some excellent instructions can be found here:

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to Diagnostic Trouble Code Information, and Diagnostic Trouble CodeChart for 1st Gen Saturns. Or, people posting here have said you can stopby any Auto Zone and have them read the codes for no charge. Any Haynes or Chilton manual will give additional info on what each code means.

If that doesn't give any results, it may be worthwhile to have your local Saturn take a look at it. Paying the diagnostic fee beats buying stuff that may not fix the problem.

Lane [ l a n e @ p a i r . c o m ]

Reply to
Lane

Coolant temperature sensors seem to be a common failure item on Saturns. (There may be two, one for the ECM with two wires and one for the gauge with one wire - the ECM one is the one that matters here.) If you take it out, you may find that the sensor end is actually cracked. I believe the newer replacement sensors are made out of brass..

Reply to
Robert Hancock

It sounds like you definitly have a coolant temp sensor issue, although you may have multiple issues. Definitly start with the sensor. On your car there are 2 sensors, you need to replace the on that gives the computer data(it has 2 wires).

When the fan turns on right at startup, I don't know any other reason for that but a faulty coolant temp sensor or computer. If the coolant temp sensor is telling the computer that the car is hot all the time, it will turn the fan on right away. A quick test would be to switch the intake air temp sensor with the coolant temp sensor(IAT is in the intake pipe) as the sensor is the same thing. The older plastic sensors were likely to bulge and/or crack(I've had both happen.......).

Good news is, the newer style brass sensor was only around $11 at NAPA when I bought mine last.

Reply to
BANDIT2941

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