joecutlass Posted July 2, 2011 Report Posted July 2, 2011 Fans stay on with key off. Anyone know whythis does it? It started doing it today and it killed my battery Quote
RobertISaar Posted July 2, 2011 Report Posted July 2, 2011 relay could have welded itself in the on position, GM released a TSB specifically about it, but what engine/year? Quote
RobertISaar Posted July 2, 2011 Report Posted July 2, 2011 yeah, go pull the relays(should be in the electrical center behind the passenger side headlight) and test them, see if the load circuit is stuck on(you'll have very little resistance between the 30 and either 87 or 87a pins, i can't remember which is used). Quote
joecutlass Posted July 2, 2011 Author Report Posted July 2, 2011 I've switched relays back and forth between fan one and two. still doing the same exact thing. Could this be the ecm? Quote
RobertISaar Posted July 2, 2011 Report Posted July 2, 2011 only one of the two stays on? which one? to see if the PCM is the problem, disconnect all 3 plugs coming out of it. Quote
RobertISaar Posted July 2, 2011 Report Posted July 2, 2011 the PCM normally shuts off after a few minutes after key-off. during that time, it's normally just watching the oil level sensor to see if it gets to a normal level quickly enough to determine whether or to turn on the "low oil" light at next key-on. if the PCM sees the coolant temp as being too high during this, it MAY turn the fans on until it thinks the coolant has gotten below an acceptable level. got a multimeter? may need to check the coolant temp sensor's resistance to see if it hasn't failed and is forcing the PCM to do something incorrectly. Quote
Oilpatch197 Posted July 3, 2011 Report Posted July 3, 2011 Could be a bad ECM, they can go out/malfunction. Go to Autozone and pull the codes, if it is a sensor I would think codes would be thrown. Had a '88 Oldsmobile Cutlass Siera, the car kept going into "limp mode"(love that term ) anyhow they had to replace it twice(GM dealer) as the first ECM(or is that PCM?) was defective, went into limp mode as well. Quote
RobertISaar Posted July 3, 2011 Report Posted July 3, 2011 Go to Autozone and pull the codes, if it is a sensor I would think codes would be thrown. sensor would only throw codes if it's WAY gone, as in a calculated 305*F or -40*F. Quote
joecutlass Posted July 3, 2011 Author Report Posted July 3, 2011 I have my multimeter with me and im at camp. I can check this in the morning. What's the resistance supposed to be on the cts? Quote
RobertISaar Posted July 3, 2011 Report Posted July 3, 2011 depends on approx coolant temp. if you let it sit overnight, it's a safe assumption that it will be within a few degrees of ambient temp. to get a truly accurate view of how the ECM is seeing it, test it directly at the PCM connector's terminals as well to rule out the wiring between the ECM and the sensor itself. the coolant temp sensor is connected to pins A17 and A31, the A plug is the clear/white one, the wires you'll be playing with are black and yellow, the connector is numbered 1-16 on one half, 17-32 on the other. it MAY have very tiny numbers cast into the plastic as well to help determine which way you're looking at it, but you should be able to figure it out just from knowing the A17 pin(which will be the first pin in one of the rows) is black and the A31 pin (which will be next to the end pin on the same row) is yellow. good luck. Quote
joecutlass Posted July 4, 2011 Author Report Posted July 4, 2011 It was a bad relay. I had a few extras in the glove. Now, im getting a weird idle. It'll start fine, few seconds later, the car will cound like a carburated truck. WTH. any idea on this? I was thinking iac? Quote
joecutlass Posted July 4, 2011 Author Report Posted July 4, 2011 It was a bad relay. I had a few extras in the glove. Now, im getting a weird idle. It'll start fine, few seconds later, the car will cound like a carburated truck. WTH. any idea on this? I was thinking iac? Quote
RobertISaar Posted July 4, 2011 Report Posted July 4, 2011 IAC, PCV, could be a few different things. Quote
joecutlass Posted July 5, 2011 Author Report Posted July 5, 2011 Im going to replace the iac, cts, and hope that works. Should the vacuum hose to the fpr have a fuel smell or no? Quote
RobertISaar Posted July 5, 2011 Report Posted July 5, 2011 vacuum line to the FPR could have a SLIGHT scent of fuel due to proximity, but remove the vacuum line and roll the key forward, maybe even start it without the line on and see if any kind of fuel is coming out of the port, you may have a ruptured diaphragm in the FPR, that would cause very odd fuel pressures and the engine would be sucking in fuel through there as well. Quote
joecutlass Posted July 5, 2011 Author Report Posted July 5, 2011 Im going to replace the iac, cts, and hope that works. Should the vacuum hose to the fpr have a fuel smell or no? Quote
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