Mechanics

SEBRING STARTS AND DIES

1997 All Other Makes All Other Models

I have a 1997 Chrsyler Sebring Convertible, 2.5L V6, 144,064 miles, that starts, revs to about 3000 RPM, and dies, here's what's been done to it;

First the car had no spark, no fuel, no nothing,
Connected scanner, no communication with the computers, read 'CCD Buss Inactive' checked the buss wires, had 2.49 on the +, 2.51 on the -, checked the connections, found a dirty connection on the heater mode door, cleaned that, and could communicate with all but the engine computer

Read the pins on the computer, the 5v feed to the TPS, MAP, and A/C switch read to ground, found the MAP sensor was shorted, replaced it, disconnected the battery for 10 minutes to reset the computer, but the computer wouldn't come back on.

Replaced the PCM, which had been a 1259AG with a 1259AI out of a wrecked 1997 convertible with the 2.5L engine, the PCM allowed me to program my car's VIN into it, whether that was because it had been out of service for so long, or what, I don't know.

Car started, but would rev high, then die, checked the fuel pressure, that was low, replaced the fuel pump, pressure is good, but car revved and died, car starts, scanner shows it's going to about 2900 RPM, then the fuel is shut off, IAC goes from 135 to 0, looked for an air leak, car would start with the intake blocked, so there was air getting in somewhere, had a friend start the car with the intake blocked, sprayed starting fluid under the plenum (I'd checked all the vacuum hoses by this time) car would continue to run as long as I sprayed fluid under the plenum on the passengers side of the engine, replaced the plenum gasket, no change, so I replaced the intake manifold gaskets, also replaced the plugs while I had the plenum off. Car still went to 2900 RPM and the computer shuts off the fuel, but, the car will no longer start with the intake blocked off, which is something. Rechecked all the vacuum lines, replaced the IAC, no change, disconnected the EGR tube from the plenum, blocked that, no change. Reran all the function tests with the scanner, everything is working, I blocked off the intake port for the IAC (outboard of the throttle plate) and the car doesn't rev up now, but it still dies, read pin 74 off the computer which supplies 12v to the Fuel Pump Relay, and it shows 12v with the key on, but goes to 0 when the car starts.

My understanding is that the computer gets the 12v from the auto shut down relay, at least that's what the wiring diagram looks like, the ASD tests ok, do I have another bad computer?

I realize I still have a problem with the IAC ports, but I need keep fuel flowing to deal with that.


This car has had the closest thing to the automotive equivalent of a nervous breakdown I've seen lately, it's got me totally frustrated, the car sounds fine during the brief time it runs, so I'm not getting into the timing belt yet.

Anyone had this problem, or have any ideas, I'm stumped

Randy
Avatar
Rogueinla
November 8, 2006.



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