bridorf Posted August 6, 2007 Share Posted August 6, 2007 1993 Leg. L Seems to happen more when it is warm outside, but sometimes it will crank longer before firing up than othe times - almost like it isn't going to start but then if you keep on crankin' it it will start - longest cranking period is about 3-4 seconds. Other times it will fire right off normally - no check engine light ever and all battery & starter terminals are tight. Any thoughts? I never have to press the accel. pedal or anything like that to make it start. Link to comment Share on other sites More sharing options...
nipper Posted August 6, 2007 Share Posted August 6, 2007 Fuel pressure regulator leaking down? Try this. Turn the car on, count to three, then see if it fires up. This gives the fuel pump a chance to pressureize the fuel system. If the problem goes away, you found the problem. Next step would be to check the fuel pressure with a gauge. nipper Link to comment Share on other sites More sharing options...
Manarius Posted August 6, 2007 Share Posted August 6, 2007 Coolant Temperature sensor? Link to comment Share on other sites More sharing options...
illanrob Posted November 10, 2007 Share Posted November 10, 2007 bridorf 1993 Leg. L "Seems to happen more when it is warm outside, but sometimes it will crank longer before firing up than othe times - almost like it isn't going to start but then if you keep on crankin' it it will start - longest cranking period is about 3-4 seconds. Other times it will fire right off normally - no check engine light ever and all battery & starter terminals are tight. Any thoughts? I never have to press the accel. pedal or anything like that to make it start." My 93 Leg L 5spd does the same, but then the Temp sensor code 2-1 flashed on the Check engine light. Also a second symptom are the cooling fans running with AC off and engine cold. The Shop Manual mentions hard starting as a consequence of a bad Temp sensor. I measured the temp sensor voltage at the ECU connector harness while driving the car voltage changed from 2.8V cold to 1.2 when engined temp is normal. Robert Illan Link to comment Share on other sites More sharing options...
illanrob Posted November 14, 2007 Share Posted November 14, 2007 With the persistent engine code 2-1 for several months, then hard cracking to get the car to run plus cooling fans running when they should not, this thread pointed to the culprit the coolant temperature sensor, CTS. This sensor gets a +5V level with a 1Kohm source resistor from the ECU. Made resistance measurements with a Volt-Ohm-Meter, VOM. The CTS behaves as a negative resistor starting at 2.5K at 20C and 0.25K at 80C, normal engine temp per shop manual. These resistance values pertain to about +3V and +1V at the ECU or the CTS. The voltage measured at the ECU connector pin 7 pin 21 (lowest connector at the ECU is the 22 pin connector under dash drivers side) after stripping some of the wire insulation. On the 93 Leg the CTS at +1.2V is too high, the ECU expects +1.0V when engine is hot. The bad CTS was left on the car and a 1.1K parallel resistor was added between pin 7 and 21 at the ECU connector. With this resistor the ECU voltage is now under 1.0V and the car runs normal. Since the CTS is continuing to wearing out, becoming less responsive to heat and not reaching the 0.25K resistance without the help of the paralled 1.1K, this is a temporary fix and will have to monitor the +1V CTS reading in months to come. Robert Illan Huntsville, AL Link to comment Share on other sites More sharing options...
GeneralDisorder Posted November 14, 2007 Share Posted November 14, 2007 That's a lot of work to go through - just replace it. They can be found used for nothing. It's just a thermistor (or RTD if you swing that way). GD Link to comment Share on other sites More sharing options...
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