rotor and cap

[kasketcarrier]

 

truck quit running while driving,took to chevy dealer,they replaced fuel filter and rotor-136 miles later truck wont start,dealer replaced plug wires ,battery,rotor&cap-120 miles later won,t start--dealer said rotor & cap ruined again they don,t know cause,replaced rotor & cap---1 day and 10 miles truck won,t start,waiting for dealer to pick truck up again says he has no idea wat is causing problem---can anyone help?

[malibu795]

what type of truck year model. when u say wont start, u mean it will roll the engine over and no spark right? check the igniton wires that go to the igniton coil for grounding ie bare parts or frayed part or losse connection on the wire(s). how can a cap& rotor wear out that fast....it has to ruin the element on the rotor and cap....they check the ignition coil?? what bout the ecm it behaving properly??

[kasketcarrier]

what type of truck year model.  when u say wont start, u mean it will roll the engine over and no spark right? check the igniton wires that go to the igniton coil for grounding ie bare parts or frayed part or losse connection on the wire(s). how can a cap& rotor wear out that fast....it has to ruin the element on the rotor and cap....they check the ignition coil?? what bout the ecm it behaving properly??

 

<{POST_SNAPBACK}>

 

 

[kasketcarrier]

it is a 1998 1/2 ton c/k work truck 6-cyl. you may be right,they SENT a tech. to my house tonight.he removed the ignition coil and said be back tomorrow morn.

[GM-Tech]

This is a known issue on the 4.3L, which I assume you have? It's not that the cap/rotor wears out, it becomes corroded from moisure build up. First it starts to misfire, then backfire and finally won't even start.

 

There are two screens in vent holes in the base of the distributor housing that have to be removed to allow better venting.

 

Also, on the 4.3 silverado's, an A/C hose runs right across the top of the distributor cap. Condensation from the hose dripping on the cap doesn't help. Go to Home Depot and buy a section of the foam pipe insulation they sell. Put a piece around the A/C line (make sure the slit is on top) long enough extend well beyond the distributor cap and tie wrap it in place.

 

I'm surprised your dealer doesn't know about this problem. Maybe we see it more frequently here in south florida where A/C is used year 'round and the temps and humidity are more favorable for this problem. There's a TSB on this problem. Tell your dealer to look for it.

 

Here, I'll save you the trouble of trying to get them to look for it. Give them this if you have a 4.3.

 

----------------------------

 

Poor Engine Performance-Misfire, Rough Idle, Stalls, Engine Cranks but Does Not Run, SES/Check Engine Light On, DTC P0300 Set (Inspect Distributor Ignition(DI) System Components, Replace as Necessary) #05-06-04-007 - (Jan 28, 2005)

 

2001-2003 Chevrolet Silverado Models

 

2001-2003 GMC Sierra Models

 

with 4.3L Gas Engine (VINs W, X -- RPOs L35, LU3)

 

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 misfire, rough idle, stall and Engine Cranks But Does Not Run. This corrosion is attributed to a lack of airflow internal to the cap caused by the vent screens being clogged with debris.

 

Correction

Important: 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.

 

Remove the vent screens and inspect the internal components of the Distributor Ignition System using the procedure listed below. If the distributor base has to be replaced, the vent screens will also have to be removed on the new distributor. 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.

 

Important: All of these inspections can be done on-vehicle.

 

 

1. 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.

2. 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.

3. 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.

 

 

 

4. Inspect the distributor vent screens (1). If the vent screens are present, remove them by using a plastic-handled, long blade awl or pick (2). Insert into the airflow vent screens and pop them out. Refer to the figure for removal procedure. If the vent screens have been removed from the base of the distributor, then check the airflow inlets for being clogged with debris.

Parts Information

Part Number

Description

 

10452458

Cap, Distributor

 

10452457

Rotor, Distributor

 

93441559

Distributor

 

15190971

Foam Sleeve

 

 

Parts are currently available from GMSPO.

 

Warranty Information

For vehicles repaired under warranty, use:

 

Labor Operation

Description

Labor Time

 

J7706

Cap, Distributor - Replace

0.5 hr*

 

Add:

Diagnosis Time

0.0-0.3 hr

 

J7707

Rotor, Distributor - Replace

0.5 hr*

 

Add:

Diagnosis Time

0.0-0.3 hr

 

J7708

Distributor Assembly - Replace

0.6 hr*

 

Add:

Diagnosis Time

0.0-0.3 hr

 

*Time includes removal of distributor vent screens and installation of foam sleeve.

 

 

 

 

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

 

 

© Copyright General Motors Corporation. All Rights Reserved.

[kasketcarrier]

the dealer sent technician out to my home on fri. he brought new ignition coil and installed it and a new set of plugs for free. truck started right up.today,sat.,truck started up so i hope that is the end of problem.thanks to malibu andgm tech for responding to my problem

[GM-Tech]

the dealer sent technician out to my home on fri. he brought new ignition coil and installed it and a new set of plugs for free. truck started right up.

 

That reminds me, we've seen quite a few with the pink power wire to the ignition coil broken inside the insulation right at the coil connector. When you move the wire, you can actually see it spark through the insulation if it's dark.

 

So, if your problem reappears, check that wire. Pull on it firmly but don't yank. If it's fractured inside the insulation, the wire will stretch right at the coil connector.