QuestionQUESTION: Hi Mark..this morning I went out to my car and for the first time it would not start right away...after about 15 mins. it fired and died..I kept trying and managed to get to run but it runs like crap...can't drive it..no check engine light so I have no codes to check...my thoughts are the fuel pump but since I'm hearing impaired I can't hear it...my wife who has good hearing couldn't hear anything either....AMM was replaced 1 year ago car has 208000 miles on it.. Help?
ANSWER: Sorry Michael, no silver bullet on this one. Start by checking for a massive air or vacuum leak. Especially the turbo plumbing. Then go to basics like spark and fuel testing. Lastly, check to see if the timing belt slipped/jumped. Let me know what you find and I will try to help more.
Happy New Year!
Mark
---------- FOLLOW-UP ----------
QUESTION: After I got your answer I went out and checked the computer and found code 113....mean anything?...
Answer Michael, here you go: The powertrain control module (PCM) monitors the temperature of the air entering the engine. The PCM supplies a 5 volt reference voltage to the Intake Air Temperature (IAT) sensor. The IAT is a thermistor that varies resistance based on temperature. As the temperature increases, resistance decreases. Low temperature results in a high signal voltage. When the PCM sees a signal voltage higher than 5 volts, it sets this P0113 check engine light code.
A code P0113 may mean that one or more of the following has happened:
Internally failed IAT sensor
Faulty connection at IAT sensor
Open in IAT ground circuit or signal circuit
Short to voltage in IAT signal circuit or reference circuit
IAT harness and/or wiring routed too close to high-voltage wiring (e.g. alternator, spark plug cables, etc.)
Faulty PCM (less likely but not impossible)
First, if you have access to a scan tool, is there an IAT reading? If the IAT reading is logical then the problem is likely intermittent. If the reading is less than -30 degrees, unplug the connector. Install a jumper wire between the harness connector signal and ground circuits. The IAT temperature reading on the scan tool should be maxed out at the high end. For example it should be 280 degrees Farenheit or higher. If it is, the wiring is okay, and it may have been the connection. If it isn't install the jumper wire between the IAT signal circuit and the chassis ground. If now the IAT reading on the scan tool is maxed out then check for an open in the IAT ground circuit. If you get no reading at all on the scan tool, it's likely that the sensor signal is open or the 5 volt reference is missing. Check using a DVOM (digital volt ohm meter) for a 5 volt reference. If it's there, then unplug the connector at the PCM and check for continuity on the IAT signal circuit between the PCM connector and the IAT connector.
Was that more information than you wanted? VBG
Happy New Year!
Mark
