Bulletin #03-06-04-041 published on 08/26/2003.
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Poor Engine Performance - Misfire, Rough Idle, Service Engine Soon/Check Engine Light Illuminated, DTC P0300 Set (Inspect DIstributor Ignition (DI) System Components and Replace As Necessary) #03-06-04-041 - (08/26/2003)
Poor Engine Performance -- Misfire, Rough Idle, Service Engine Soon/Check Engine Light Illuminated, DTC P0300 Set (Inspect Distributor Ignition (DI) System Components and Replace As Necessary)
2001-2003 Chevrolet Astro, Blazer, Express, S-10, Silverado
2001-2003 GMC Jimmy, Safari, Savana, Sierra, Sonoma
2001 Oldsmobile Bravada
with 4.3L, 5.0L or 5.7L Gas Engine (VINs W, X, M, R -- RPOs L35, LU3, L30, L31)
Condition
Some customers may comment on poor engine performance and the Service Engine Soon/Check Engine light being illuminated. Upon investigation, the technician may find DTC P0300 set.
Cause
This condition may be due to high levels of internal corrosion in the distributor, causing spark to go to the wrong cylinder. This corrosion is attributed to a lack of air flow internal to the cap caused by the EIP screens being clogged with debris.
Correction
Inspect the internal components of the Distributor Ignition System using the procedure listed below. A new distributor base has been released for service with improved airflow screens.
Inspect the distributor cap. You may notice a white residue on the cap walls. For higher mileage occurrences, the interior of the cap may have changed to medium brown in color.
Inspect the distributor rotor. You may notice the presence of black streaks on the plastic surface. More typical evidence would be visible green spots on the copper surface of the rotor segment.
Inspect the distributor base. You may notice high levels of surface rust on the distributor shaft or surface contamination on the sensor hold down screws.
Inspect the distributor EIP screen. The screens should be free of any debris and the mesh should be visibly porous.
All of these inspection can be done on-vehicle. If there is evidence of this internal corrosion, replace the affected component. Refer to the appropriate procedure in the Engine Controls sub-section of the applicable Service Manual.
In addition, it has been determined on the Sierra and Silverado applications with the 4.3L engine that the A/C accumulator line is routed directly above the distributor area and condensation from that line can aggravate the corrosion condition. For these vehicles, install the foam sleeve, P/N 15190971, to the A/C line. Cut a slit in the sleeve and secure to the line using tie-straps.
Parts Information
Part Number
Description
10452458
Cap, Distributor (V6)
10452457
Rotor, Distributor (V6 and V8)
93441559
Distributor (V6)
10452459
Cap, Distributor (V8)
93441558
Distributor (V8)
15190971
