Questionhow to fix this error code
AnswerHi Manny,
There are many possibilities for a multiple cylinder misfire. Here is one you might consider:
DATE: Aug. 17, 2001
This bulletin is supplied as technical information only and is not an authorization for repair. No part of this publication may be reproduced, stored in a retreival system,
or transmitted, in any form or by any means, electronic, mechanical, photocopying, or otherwise, without written permission of DaimlerChrysler Corporation.
SUBJECT:
Rough Idle, Hard Start, Start & Stall
OVERVIEW:
This bulletin involves installing a revised EGR valve.
MODELS:
1995 - 2000 (JA) Breeze/Cirrus/Stratus
1996 - 2000 (JX) Sebring Convertible
NOTE: THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 2.5L ENGINE.
SYMPTOM/CONDITION:
Vehicle may intermittently exhibit any of the following conditions:
• Rough engine idle.
• Hard start or long crank after hot soak.
• Start and stall when started with cold engine.
• Diagnostic Trouble Code (DTC) P0300, Multiple Cylinder Mis-fire.
DIAGNOSIS:
Using the Diagnostic Scan Tool (DRB III®) with the appropriate Diagnostic Procedures,
verify all engine/transmission systems are functioning as designed. If other DTC’s are
present, record them on the repair order and repair as necessary before proceeding
further with this bulletin. If the condition(s) can be duplicated or is described by
the customer, it may be caused by the EGR valve being stuck partially open. To
confirm whether or not the valve is stuck partially open:
1. If the condition(s) can be duplicated, then block off the EGR passageway to the
intake manifold. If the condition(s) disappear, but will reappear when the EGR
passageway is re-opened, perform the Repair Procedure.
2. If the condition(s) cannot be duplicated, but are described by the
customer, perform the Repair procedure.
PARTS REQUIRED:
Qty. Part No. Description
1 04287646AC Valve, EGR
REPAIR PROCEDURE:
The other possibilities are more numerous:
The codes are based upon the detection of minor missing which causes subtle differences in the rpm as each cylinder fires to produce its rotational input (crankshaft speed sensor is the detector involved). The Chrysler troubleshooting manual lists the possible causes as:
secondary ignition wires, puel pump or fuel filter, injector harness connectors, ignition coil circuit, spark plugs, mechanical engine problem, contaminated fuel, water in fuel, PCM grounds, Injectors, Restricted exhaust, intake restriction, PCM, evap system, EGR system, Air gap at high rpm's, damaged sensor trigger wheel. That is quite a list!
The approach suggested is to check all electrical connectors and wiring, then do the tests in the following order:
secondary ignition
fuel delivery
engine vacuum
PCM power and ground connections
engine mechanical
The first one uses an engine analyzer scope to look at the high voltage pattern, then spray water on the cables to see if it changes. The possible repairs: individual spark plugs, coil or cable replacement
The second one involves pressure measurement and from there a variety of possible solutions
The third involves reading the intake manifold vacuum to see if it is steady at between 13 and 22 inches of HG. and if not the suspects depend upon the pattern shown by the gauge.
The PCM involves checking various wires at the PCM plugs
The last involves engine compression testing and a variety of other mechanical checks.
So I guess that beginning with the ignition wires makes sense unless you have a scope and the experience/knowledge at interpreting the patterns. You might try looking at the wires in the dark with the engine idling, then also spray some water mist on them to see in either case if you see arcing which would be a sign that the wires' insulation is breaking down. Then measure the coil resistances. If it passes that, then focus on the fuel filter and pump.
Those 'exhaust' my ideas.
Roland
