Car

Ask a Mechanic Online and Get Answers to Your Car Questions

Ask an Expert,
Get an Answer ASAP!

Car

98 blazer 4.3 miss fire #3cyl.at idle, raise rpm to 1800 stops

Customer Question
missfiring,raise rpm to 2200 starts...
98 blazer 4.3 miss fire #3cyl.at idle, raise rpm to 1800 stops missfiring,raise rpm to 2200 starts missing on #4 cyl.
Submitted: 7 years ago.Category: Car
Show More
Show Less
Ask Your Own Car Question
Answered in 27 minutes by:
6/5/2010
Auto Mechanic: Roadside Jerry, Auto Mechanic replied 7 years ago
Roadside Jerry
Roadside Jerry, Auto Mechanic
Category: Car
Satisfied Customers: 2,948
Experience: Auto Mehanic 39 years,30 with the NYPD Fleet Service Division
Verified

HelloCustomerThere have been many problems with the injector systems on your model vehicle with vortec engines. Here are a couple of the service bulletins that cover that. They would need to either be cleaned with a special cleaner, (the dealer would be the best one to do that)since they have the proper equipment to clean using high pressure .

The best fix,although more expensive would be to convert the system to the new injector style.

 

 

Fuel System - MIL ON/Rough Idle on Start-Up
Notes

File In Section: 06 - Engine/Propulsion System

Bulletin No.: 00-06-04-003B

Date: February, 2003

TECHNICAL

Subject:
Rough Idle After Start, And/Or A Service Engine Soon (SES) Light
(Unstick And Clean Central Sequential Fuel Injection (CSFI) Poppet
Valves or Convert to MFI)

 

Models:
1995-2002 Chevrolet and GMC S/T Models
1996-2002 Chevrolet and GMC C/K, M/L, G, P Models
1996-2001 Oldsmobile Bravada
1999-2000 Cadillac Escalade
with 4.3L, 5.0L or 5.7L Engine (VINS W, X, M, R - RPOs L35, LF6, L30, L31)
Except 2002 VIN X - RPO LU3 Models

 

This bulletin is being revised to update the Warranty Information. Please discard previous copies of Corporate Bulletin Number 00-06-04-003B with warranty chart (Section 06 - Engine). This copy is for Dealers in the state of CALIFORNIA ONLY.

Condition

Some customers may comment on rough idle after start-up, especially if the vehicle has sat overnight. These symptoms may be intermittent. The Service Engine Soon (SES) light may also be illuminated. Current misfire or history misfire codes may be detected with the Tech 2 scan tool.

Cause

A deposit build-up on the CSFI poppet valve ball and/or seat may cause the poppet ball to stick open or closed. In either case, the specific cylinder will be mis-fueled, resulting in a cylinder mis-fire condition.

Correction

A new injector unsticking and cleaning process has proven to be effective in restoring poppet valves to an "as new" condition. CSFI injector replacement should NOT be considered as a correction for this customer concern.

Check the vehicle history to determine if the vehicle is returning for a second fuel system repair for this condition. If the fuel system has been repaired for this condition previously, then inform the customer that an alternate fix is available. A new MFI fuel system has been developed that will back service the CSFI fuel system. The MFI fuel system eliminates the CSFI poppet valve ball and seat. The CSFI fuel system will need to be replaced as a unit. Refer to Central SFI to MFI Conversion instructions in this bulletin.

Notice : Individual CSFI injectors can not be replaced with MFI injectors. The entire CSFI fuel meter body will need to be replaced. The bracket used to retain the injectors in the fuel meter body is different between the CSFI and MFI unit. The unit may not seal if you mix injectors. Severe engine damage could result.

 

Cleaning the CSFI injectors is the preferred repair. The CSFI unit should not be replaced until cleaning has been attempted. If the vehicle should return for the same repair, then the CSFI unit can be replaced with an MFI unit. If the vehicle is out of warranty, the customer should be given the option of which fix to pursue.

Important : "GM of Canada" dealers require District Service Manager approval prior to replacing the CSFI unit with a MFI unit under warranty.

 

The first step of this process is to use the J 41413 Evap Pressure/Purge Station, in conjunction with the J 44466-10 pressure regulator/hose assembly, to provide the required high pressure (150 psi) source to perform the unsticking procedure. The J 39021 fuel injector tester and accessories provide the means to "energize" the injector. Some later model-year vehicles may utilize the Tech 2(R) to "energize" the injectors.

The second step of this process is to run the engine on a solution of 10% Top Engine Cleaner and 90% gasoline. This will effectively clean any deposits from the ball and seats of the poppets. It is very important that the engine fuel system is separated from the vehicle fuel system. Top Engine Cleaner may have detrimental effects on the fuel pump.

 

 

 

Campaign - Fuel Injector Sticking Closed
Notes

File In Section: 06-Engine Emissions

Bulletin No.: 99066F

Date: March, 2003

SPECIAL POLICY

SUBJECT:
99066F - SPECIAL POLICY ADJUSTMENT - SEQUENTIAL CENTRAL PORT
FUEL INJECTION (SCPI) FAILURES IN CALIFORNIA ONLY (YF5
EMISSION EQUIPPED)

 

MODELS:
CERTAIN 1996, 1997, 1998, 1999, 2000, 2001, 2002 S/T, M/L, C/K, G,
P, W4/NPR TRUCKS AND 2003 NPR TRUCKS EQUIPPED WITH 4.3L
(RPO L35 - VIN CODE W OR RPO LF6 - VIN CODE X), 5.0L (RPO L30
- VIN CODE M) OR 5.7L (RPO L31 - VIN CODE R) ENGINE AND
CALIFORNIA EMISSION EQUIPPED (RPO YF5)

 

This bulletin is being revised to add the 2002 and 2003 model years to the SCPI Special Policy on certain S/T, M/L, C/K, G, P and W4/NPR truck models. Please discard Special Policy Bulletin Number 99066E, dated February, 2003.

CONDITION

Some customers of 1996, 1997, 1998, 1999, 2000, 2001, 2002 model year S/T, M/L, C/K, G, P, W4/NPR trucks and 2003 NPR trucks, that are registered in California, equipped with 4.3L (RPO L35 and VIN Code W, or RPO LF6 and VIN Code X), 5.0L (RPO L30 and VIN Code M) or 5.7L (RPO L31 and VIN Code R) engine, and California emissions (RPO YF5), may experience a "Service Engine Soon" light, misfire, rough idle or hard start due to a deposit build-up on the Sequential Central Port Fuel Injector (SCPI) poppet valve(s). The deposit build-up may cause injector poppets to stick closed. Certain fuels have been found to interact with the SCPI system to cause the deposits.

SPECIAL POLICY ADJUSTMENT

This special policy covers the SCPI failure condition described above for a period of ten (10) years or 200,000 miles, whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership.

The repairs will be made at no charge to the owner. This special policy applies ONLY to repairs requiring SCPI system servicing, injector cleaning and/or MFI assembly replacement of the SCPI system. The customer should not be charged for performing a system check when it is determined that the SCPI system is not the cause of a customer complaint (labor operation T5532 is provided to submit /laims for such system checks). Atepadditional necessary diagnosis and repairs that are not related to the SCPI condition are not covered by this special policy. The customer should be informed that any further service that is not covered by new vehicle warranty will not be covered by this policy.

VEHICLES INVOLVED

Involved are certain 1996,1997,1998,1999, 2000, 2001, 2002 S/T, M/L, C/K, G, P, W4/NPR and 2003 NPR model vehicles, registered in California, equipped with 4.3L (RPO L35 - VIN Code W, or RPO LF6 - VIN Code X), 5.0L (RPO L30 - VIN Code M) or 5.7L (RPO L31 - VIN Code R) engine; and California emissions (RPO YF5). This Special Policy covers all vehicles within these model years, with these engine and emissions RPO's.

Ask Your Own Car Question
Ask Roadside Jerry Your Own Question
Roadside Jerry
Roadside Jerry
Roadside Jerry, Auto Mechanic
Category: Car
Satisfied Customers: 2,948
2,948 Satisfied Customers
Experience: Auto Mehanic 39 years,30 with the NYPD Fleet Service Division

Roadside Jerry is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry.

Stephanie PElm City, NC

used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future.

David L.Richmond, TX

9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much.

PhilMarysville, CA

Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible.

CharlesWalnut Creek, CA

As a single woman, I really appreciate an excellent and affordable opinion.
Thank you Geordie, I will not hesitate to contact justanswer in the future!

SueCharleston, WV

Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff.

JimCastleberry, FL

The nearest Volvo dealer is 160 miles away. Best $15 bucks I have spent in a long time!

Paul MCorpus Christi, TX

< Previous | Next >

Meet the Experts:

Chris (aka-Moose)

Chris (aka-Moose)

Technician

1,243 satisfied customers

16 years of experience

Ted G.

Ted G.

ASE Certified Technician

1,724 satisfied customers

20 years auto repair experience, ASE Master Tech, Mechanical Failure consultant, Expert Witness

George H.

George H.

ASE Certified Technician

1,537 satisfied customers

ASE Master Tech 15+ yrs, AAS Automotive Technology, Factory trained Asian specialist

GM Tech (Cam)

GM Tech (Cam)

Auto Service Tech

669 satisfied customers

GM Grand Master Technician 2007. 14 years experience.

Amedee

Amedee

Former ASE Master Tech

2,520 satisfied customers

ASE certified tech advanced level specialist. Wisconsin certified emissions state inspector

Jerry

Jerry

Master Mechanic

2,181 satisfied customers

ASE master, 30+ years. All makes and models. Trouble shooter, shop forman, service manager

Richard

Richard

ASE Certified Technician

1,000 satisfied customers

12 years Ford Lincoln/Mercury Jaguar dealership as a technician and shop foreman reparing all makes

< Previous | Next >

Related Car Questions
I'm wondering if Exxon Synergy gas will hurt or harm my 2008
I'm wondering if Exxon Synergy gas will hurt or harm my 2008 Prius. … read more
K. Wiggins
K. Wiggins
ASE Certified Technician
Associate Degree
3,000 satisfied customers
I need to know the type of transmission is in a 2006 Dodge
I need to know the type of transmission is in a 2006 Dodge Caravan (3.3L) and also how many speeds there are: VIN # 1D4GP25R36B646548. Thank you.… read more
Edward
Edward
Professional at Justanswer.com
Associate Degree
3,175 satisfied customers
I have a 1995 C280 and there is no braking on the passenger
I have a 1995 C280 and there is no braking on the passenger side front wheel. … read more
Expert
Expert
15 satisfied customers
My truck is sputtering but only when I'm under load like
My truck is sputtering but only when I'm under load like during acceleration, I am throwing no codes so I'm not sure how to proceed … read more
vwtech0405
vwtech0405
VW Technician
Associate Degree
9,666 satisfied customers
My cadillac is a 2008 cts 3.6. It is cranking but not
My cadillac is a 2008 cts 3.6. It is cranking but not starting … read more
David Craig
David Craig
OWNER/MECHANIC
Associates
4,396 satisfied customers
I am installing a back up camera. want to wire to the back
I am installing a back up camera. want to wire to the back up light. which color is the backup light and where is best place to ground? … read more
Todd M
Todd M
Owner
ASE Certification
1,484 satisfied customers
A problem with the heater. When the truck is idling no
When the truck is idling no matter what the engine temp gauge shows the heater only blows cold air as soon as RPM is up like driving down the road above 1000 to 1500 RPM the heater works like a blast furnace no problem … read more
Steve
Steve
Master\u0027s Degree
954 satisfied customers
I have a 2002 chevy carla SS, 3800 engine, with a check
Second opinion] I have a 2002 chevy monte carla SS, 3800 engine, with a check engine light problem. Code showed 02 sencers. Changed both, cleared codes and drove it. After driving a little ways, check… read more
Matt
Matt
Engineer
Bachelor\u0027s Degree
5 satisfied customers
I purchased a Helix column STCOL2 will the Ididit wheel
i purchased a Helix column STCOL2 will the Ididit wheel #201463081590 fit this column … read more
AutoDoc
AutoDoc
Shop Owner
Bachelor\u0027s Degree
390 satisfied customers
2000 kia sportage runs at idle its 4x4 se 2.o engine
2000 kia sportage runs at idle its 4x4 se 2.o engine sluggish up hill no power ,put in new fuel filter tps no chonge … read more
JOHN aka Eauto
JOHN aka Eauto
self employed
High School or GED
10,348 satisfied customers
The new cv shafts for my Pulsar N16 1.8 litre automatic
The new cv shafts for my Pulsar N16 1.8 litre automatic turned out to be for a manual transmission. Have now fitted the correct shaft on the driver side. Is the passenger side shaft the same for both … read more
Jay
Jay
Shop Forman / Lead Tech
Vocational, Technical or Trade Scho
20,878 satisfied customers
Have a 2014 Range Rover sport with jag/Rover 3.0 6
Have a 2014 Range Rover sport with jag/Rover 3.0 6 cylindrical gas supercharge motor. Replacing my timing chains and have no spec showing the setting for the chains. Can someone please provide diagram… read more
Eric
Eric
Retired
N/A
31,322 satisfied customers
Does the dashboard have to be replaced on a 2017 Maserati
does the dashboard have to be replaced on a 2017 Maserati Levante after passenger air bag deploys? … read more
Expert
Expert
15 satisfied customers
2007 Envoy won't shift out of neutral. Actually the shift
2007 Envoy won't shift out of neutral. Actually the shift indicator says it is in drive or reverse, but the wheels spin freely (will roll down a hill). … read more
Steve
Steve
Master\u0027s Degree
954 satisfied customers
Misfiring. 92 gmc dually like 120, 000. 3500. It gave me a
misfiring JA: How many miles are on the car? Is it a steady misfire? Or random? Customer: 92 gmc dually like 120, 000 JA: What is the model of your '92 GMC? Customer: 3500 JA: Are you fixing your 3500… read more
rpmdiag
rpmdiag
High school
7,271 satisfied customers
Codes indicate misfire cylinder 3 and o2 sensor. When this
Codes indicate misfire cylinder 3 and o2 sensor. When this started a few weeks ago, since we have 150k on 2011 Odyssey I decided to replace plugs and all coil packs. It misses at 1000-1500 rpms in hig… read more
Steve
Steve
Master\u0027s Degree
954 satisfied customers
I have a 2011 ford ranger 3.0 litre. I started it mondaqy
hi i have a 2011 ford ranger 3.0 litre. I started it mondaqy morning and it ran for a few seconds and stopped. It turned over ok but not start sounded like fuel so i pumped the primer 3 or 4 times and… read more
Chad Farhat
Chad Farhat
Owner
Associate Degree
4,410 satisfied customers
My traction control light that comes on when you start the
My traction control light that comes on when you start the car will go off and as I am driving, it comes on and stays on. I bought this car in 2011 and it was a brand new 2012 Nissan Altima. In all of… read more
jim
jim
Vocational, Technical or Trade Scho
1,317 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x