Help - running rough, new plugs, wires, cap and rotor

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99Yuk

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scottg918514

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Other things to check:

1. clean throttle body
2. Maybe seafoam gas and engine (vaccum line)
3. Maybe weezing, not getting enough air.

If you're check engine light was on, there should have been a code registered on your computer. Autozone should have told you the code and its meaning.
 
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gulleyman

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Other things to check:

1. clean throttle body
2. Maybe seafoam gas and engine (vaccum line)
3. Maybe weezing, not getting enough air.

If you're check engine light was on, there should have been a code registered on your computer. Autozone should have told you the code and its meaning.

Thanks scottg918514, was gonna try the Seafoam. Before I did the tune up there was a misfire code, they told me I probably needed to change the plugs, wires, cap and rotor. Didn't solve the problem though...

So what gives??? What do we really want to be ordering?
I couldn't make any sense out of it either. One of these is less than $300 though. I sent an email to their customer service department to try and sort it out. They said I needed GM PART # 93441235, $313.46....wonder what the difference is?
Anyone else have a better, or more cost effective idea?
 
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SunlitComet

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This may help.
They were revised for californians. Attachment with file name that ends in 942 is for bottom bulletin.



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.

Parts Information



Cleaning Procedure Parts



CSFI to MFI Conversion Parts



Parts are currently available from GMSPO.

Warranty Information
Important : Some California vehicles may be covered by Special Policy 99066E if built with California Emissions RPO YF5. If the vehicle is covered by the special policy, then that warranty information should be used.

For vehicles repaired under warranty, use information contained in Special Policy 99066E.



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

And Another:

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 claims for such system checks). Any additional 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.

PARTS INFORMATION
 
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gulleyman

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Wow, I think that about sums it up...
Thanks sunlitcomet:waytogo:, now let's figure out if GMpartsdirect is the best place to buy the MFI and we've got this licked:rockit:

:fish_h4h:Come on guys, I know this is something that a BUNCH of us have had or will have to replace.:fish_h4h:
 

Mcoffey24

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I also had a misfire problem that I was fighting for about a year. I replaced 3 injectors before I finally got a new spider in MFI. Never had a problem since.
I was able to get mine from Autozone for $300 but it was on a company discount.
 

SunlitComet

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I will be getting mine from kragen for less then $373 w/tax.

Includes spider and new bracket made by BWD and felpro gasket set.

add 113 for delphi parts(oem).

or you can try http://www.gmpartsgiant.com/

A dealership in Ca. with good prices and ships.

$352 for the v8 module which is cheaper then kragens oem price.

just verify part number applicability.

On second thought I am going to use giant instead for oem parts.
 
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gulleyman

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Oookay, so the new MFI is in place and it's STILL running rough :Frustrated:
So I have them checking the distributor now too, haven't heard back from them yet. Guess I'll start going through the list scottg918514 gave me. Anyone else got some insight on this one? Need all the help I can get...
 

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