Newbie to working on mine. Is this P0301 over my head?
#1
12-31-2009, 10:20 AM
Newbie to working on mine. Is this P0301 over my head?
So I did my research now that I've fixed a few simple sensor things on my wife's Altima (including having to diagnose/fix me leaving a paper towel in the airbox being sucked onto the throttle valve.)
Anyway, dug in the forums, found the code and the symptom that triggers it and the solution. FINALLY! 2 years ago an awesome tech at the dealer said what it was known to be and the cost. Didn't have the money and have lived with it ever since. Now that your forum has pinned it down for me again, I want it fixed. Is this a job I could trust to a simple mechanic local? It sounds WAY too complex for me. Read this from the code database of your site and you tell me:
https://blazerforum.com/forum/diagnostic-trouble-codes-dtcs-49/p030x-explained-x%3D0-1-2-3-4-5-6-a-35153/
Thanks,
Butch in Asheville
Anyway, dug in the forums, found the code and the symptom that triggers it and the solution. FINALLY! 2 years ago an awesome tech at the dealer said what it was known to be and the cost. Didn't have the money and have lived with it ever since. Now that your forum has pinned it down for me again, I want it fixed. Is this a job I could trust to a simple mechanic local? It sounds WAY too complex for me. Read this from the code database of your site and you tell me:
https://blazerforum.com/forum/diagnostic-trouble-codes-dtcs-49/p030x-explained-x%3D0-1-2-3-4-5-6-a-35153/
Subject: SES Light and P0300 When Towing , Cruising Uphill or on Hard Acceleration - 4.3 5.0 5.7 accelerate cruise cylinderhead RPO L30 L31 L35 LF6 LU3. DTC P0300 P0301 P0302 P0303 P0304 P0305 P0306 P0307 P0308 PIP3081 - (07/23/2004)
Models: (96-02 Chevrolet Astro) and (96-02 GMC Safari) and (96-00 Old Body Style Chevrolet Suburban) and (96-00 Old Body Style Chevrolet Tahoe) and (96-02 Chevrolet Express) and (96-00 GMC Yukon) and (96-00 Chevrolet Old Body Style C/K Truck) and (96-00 GMC Old Body Style C/K Truck) and (96-02 GMC Savana) and (96-99 P32 Cab and Chassis) and (96-02 Chevrolet S-10) and (99-02 Chevrolet Silverado with 4.3L V-6 Engines (96-02 GMC Sonoma) and (96-02 GMC Sierra with 4.3L V-6 Engines).
The following diagnosis might be helpful if the vehicle exhibits the symptom described.
Condition/Concern:
The vehicle may exhibit a SES Light due to a P0300 and misfire. If the misfire is related to the information below, it will typically happen while cruising uphill, pulling a trailer or on hard acceleration and then stop misfiring shortly after returning to an idle. Typically, cylinders 3,4,5 or 6 will be the ones to experience this.
Recommendation/Instructions:
If the P0300 diagnostics did not isolate a concern, the following may help:
Remove the valve cover, valve springs and valve seals on the effected cylinder or cylinders. A small wire tie or rubber bands can be placed in the valve stem keeper groove to prevent the valve from falling into the cylinder. Rotate the valve while moving it up and down in the guide to see if it binds. If a binding valve is found, remove both cylinder heads and use either of the following methods to increase the stem to guide clearance:
* Send the head out to a machine shop and advise them to increase the valve stem to guide clearance to 0.002 inch per guide.
* Hone the guide with a 9 mm hone, such as Snap On BCG249, until a clearance of 0.002 inch is obtained. This will usually take about 4 strokes of the hone.
Reassemble the cylinder heads using new valve seals.
Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
__________________
Models: (96-02 Chevrolet Astro) and (96-02 GMC Safari) and (96-00 Old Body Style Chevrolet Suburban) and (96-00 Old Body Style Chevrolet Tahoe) and (96-02 Chevrolet Express) and (96-00 GMC Yukon) and (96-00 Chevrolet Old Body Style C/K Truck) and (96-00 GMC Old Body Style C/K Truck) and (96-02 GMC Savana) and (96-99 P32 Cab and Chassis) and (96-02 Chevrolet S-10) and (99-02 Chevrolet Silverado with 4.3L V-6 Engines (96-02 GMC Sonoma) and (96-02 GMC Sierra with 4.3L V-6 Engines).
The following diagnosis might be helpful if the vehicle exhibits the symptom described.
Condition/Concern:
The vehicle may exhibit a SES Light due to a P0300 and misfire. If the misfire is related to the information below, it will typically happen while cruising uphill, pulling a trailer or on hard acceleration and then stop misfiring shortly after returning to an idle. Typically, cylinders 3,4,5 or 6 will be the ones to experience this.
Recommendation/Instructions:
If the P0300 diagnostics did not isolate a concern, the following may help:
Remove the valve cover, valve springs and valve seals on the effected cylinder or cylinders. A small wire tie or rubber bands can be placed in the valve stem keeper groove to prevent the valve from falling into the cylinder. Rotate the valve while moving it up and down in the guide to see if it binds. If a binding valve is found, remove both cylinder heads and use either of the following methods to increase the stem to guide clearance:
* Send the head out to a machine shop and advise them to increase the valve stem to guide clearance to 0.002 inch per guide.
* Hone the guide with a 9 mm hone, such as Snap On BCG249, until a clearance of 0.002 inch is obtained. This will usually take about 4 strokes of the hone.
Reassemble the cylinder heads using new valve seals.
Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
__________________
Butch in Asheville
#2
12-31-2009, 10:30 AM
While that could be an issue, that scenario is quite rare. Have you performed a compression and leak down test on the cylinders? This will allow you to assess the health of the #1 cylinder as compared with the rest.
One other scenario is a faulty or stuck poppet nozzle on the #1 cylinder. This is a bit more common than a sticking valve.
What have you tried thus far to remedy the problem?
One other scenario is a faulty or stuck poppet nozzle on the #1 cylinder. This is a bit more common than a sticking valve.
What have you tried thus far to remedy the problem?
#3
01-01-2010, 01:09 PM
While that could be an issue, that scenario is quite rare. Have you performed a compression and leak down test on the cylinders? This will allow you to assess the health of the #1 cylinder as compared with the rest.
One other scenario is a faulty or stuck poppet nozzle on the #1 cylinder. This is a bit more common than a sticking valve.
What have you tried thus far to remedy the problem?
One other scenario is a faulty or stuck poppet nozzle on the #1 cylinder. This is a bit more common than a sticking valve.
What have you tried thus far to remedy the problem?
Didn't find those mentioned but I called a local mechanic who said he needed to do the leak down test first before going into the scenario I posted. And if you can post a link to info about a stuck poppet nozzle, I would appreciate it. I'm now learning that even if I can't work on my car, if I research before walking in the door, it even helps the mechanic.
Thanks so much for mentioning that.
Thread
Thread Starter
Forum
Replies
Last Post
KyFritz02Xtrm
Paint, Body, & Interior
0
09-26-2009 12:48 PM
