QuestionYesterday when I turned off the engine and had taken the keys out of the ignition I noticed the radiator fan was still running. I gave it about 20 minutes, went back outside and the fan was still running. So I disconnected battery because I didn't want to drain it. Later I reconnected the battery, fan started back up so I found out how to disconnect the radiator fan. Later when I went to start the car it would crank over, but would not start. We have checked spark to the coil and it was good, checked a spark plug and it was okay.
Realized that the oil was very low, so we added oil. The fan finally stopped running constantly (we don't know why, but it just stopped) but the car still won't start. The battery is charged, but still no start.
We did check the diagnostic trouble codes, and got 12-55, but we already knew the battery had been disconnected (which I believe 12 means). It is a v6 3.0L engine. There had been no problems starting it until yesterday. We have been having a heat wave in the area for the last few days, although I'm not sure if that's relevant. Thanks for any help!
AnswerHi Jenni,
I suspect that the points on the radiator fan relay were stuck together which would explain the non-stop fan.
When you say "checked spark to the coil" do you mean that you checked the 12V supply to the spark coil + post when cranking it for 5 seconds, or do you mean that you tested for actual spark at the end of the spark cable that enters the distributor cap by holding its tip 1/4" from the cylinder head while a helper cranked it for 5 seconds or did you check the spark at one of the spark plug caps using an inserted screwdriver with its shaft held 1/4" from the head? Which you did would be relevant for me to know. I would prefer that you verified spark using the screwdriver shaft held 1/4" from the block as this proves spark at the plug proper, or you can remove a plug and then insert it back in the cap and hold the threads against the block while cranking and watch for spark to jump the plug gap.
Do you hear the fuel pump run for a second or so when you turn the ignition to the run position?
Do you hear the injectors make any clicking sounds when you are cranking the engine?
All those would help clarify if we have timing signals and that the ASD relay is closed when cranking.
In light of the "oil was very low" observation you might want to check the compression of a several of the cylinders just to rule out any damage to cylinder/piston interfaces.
You would want it to read at least 135 psi when cranking with all plugs removed so that the cranking speed is 250 rpm.
So if we have compression and spark and fuel that is properly synchronized, we get into some of the more subtle issues like mixture (MAP/coolant temp sensor/fuel pressure) and throttle position sensor and idle control motor any of which could be off value but not so far as to set a fault code. There are tests for all those which I can fill you in about. But if you would be willing to focus on the above items and let me know if one of them resolves the problem and if not then we can approach the subtle ones.
If I am maxed out write me back by the comments section of the "thank and rate" tab below. I only take one question at a time so it isn't so easy to find me available. Otherwise I get overwhelmed.
Roland
P.S. If you have a car that was made for delivery in California then the engine will have an egr valve which might be stuck ajar and prevents a mixture necessary to idle the engine. But this is moot if it was a federal/canada delivery car.
