Question I just tested the battery and the guys at Autozone say it's fully charged and working perfectly. We have spark and I cleaned and tightened the battery terminals, to no avail. Here's another bit of data I noticed recently, when the outside temperature is cold (about 50 or below), it seems to start right up. Keep in mind that if the car's been running for awhile before I try to start it, it also starts more readily. This seems paradoxical, but go figure. Any ideas?
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Followup To
Question -
Hello Mr. Niemi,
My 1993 240 was having trouble starting, it would turn, the engine would shudder and stop turning over for a second, then start up. I tried fixing it myself to no avail. The problem has gotten gradually worse to where, now, it will start, but it takes several minutes to do so (cranking it for a few secs, waiting and retrying). It seems as though when it starts shuddering and such, it take one or two more cranks and then it will start. If the car was running for awhile close to trying to restart it, it's less likely to have the problem. I can tell you that fuel pressure is OK, a bit high if anything, and it's getting a good spark. At this point I'm running out of ideas. Any help you can provide would be greatly appreciated. Thanks so much for your help in advance.
Answer -
Mike,
Test the fuel pressure. Make sure the feed pump is working. And pull off the vacuum line from the fuel pressure regular to see if it is leaking. Read any codes in the system and follow them out. The fuel pump relay and the Mass air flow sensor along with the flywheel pick up all have a high failure rate.
Question
We tested the fuel pressure, it read 37 psi and held consistently throughout startup. We changed the fuel pressure regulator and checked the vaccum line to no avail. I'm not getting any codes, and the fuel pump relay, mass air flow sensor, and crankshaft position sensor were all changed recently in response to an unrelated problem. The problem feels electrical to me. It might be unrelated, but the voltmeter I installed read high periodically. If I tap on the meter, it goes back to reading OK. Could it be a bad ground with the battery?
Answer
Mike,
You are saying that the starter is hanging up and not turning over the engine. Is the battery strong enough? When the car will not start can you jump the starter and get the engine to crank? Test the starter draw, make sure that the battery cables are clean and tight. Do you have spark, no try the power stage.
AnswerMike,
There is plenty of power in the battery and there is spark, so how about fuel? Test the fuel pressure and also remove the vacuum line from the pressure regulator and see if gas comes out. That would indicate a leaking pressure regulator. Are you sure that the fuel pumps are working both under the car and in the tank. If all that works then you be have a bad temp sensor. You can ohm out the sensor at the control unit,if you have the chart to follow.
