Subject: | No Start, Hard Start, Or Rough Idle After Start (Clean CPI Poppet
Valves) |
Models: | 1992-1995 Chevrolet and GMC M/L, S/T Models |
| 1992-1995 Oldsmobile Bravada |
| with 4.3 L Engine (VIN W -- RPO L35) |
Condition
Some customers may comment on no start, hard start, rough idle after
start, surge, or other driveability concerns related to the fuel system (clean
CPI Poppet nozzles).
Cause
Under certain conditions, fuel elements may deposit on the poppet balls,
seats, or pintles, which can cause the poppet balls to stick in either an
open or closed position.
Correction
Follow the Strategy-Based diagnostics for your customer's specific driveability
concern. If diagnosis leads to sticking poppet nozzles, this cleaning procedure
should be performed prior to replacement of the CPI injector.
CPI Injector Cleaning Procedure
- Loosen the fuel filler cap to relieve vapor pressure in the fuel
tank.
- Raise the vehicle on a hoist.
- Locate the underbody fuel line (1) junction
point:
• | For S/T and L-van, it is along the left frame rail at approximately
mid-vehicle. |
• | For M-van, it is behind the left-front wheel housing. |
Caution: Considerable fuel leakage may occur. Make sure that protective eyewear
is worn, and that suitable fuel containment measures are taken.
- Loosen and disconnect both the pressure and return lines at their junction
points. The fittings towards the front of the vehicle (both pressure and return)
have "male" fittings, and the fittings towards the rear of the vehicle have
"female" fittings.
- Install the J 44466-2 (1) (this
hose has two 90 degree male fittings and no service port) to the "fuel
tank" side of the fuel pressure and return lines. Installation of this hose
eliminates the need to electrically disable the fuel pump and allows fuel
to recirculate to the fuel tank.
Important: This cleaning procedure and service tools separate the fuel tank and
pump from the cleaning process. Do not allow the Top Engine Cleaner solution
to reach the fuel tank and/or pump. Top Engine Cleaner solution may cause
a failure of the fuel pump.
- Install the J 44466-1 (3) (this hose has two female fittings
and a service port) to the "engine side" of the fuel pressure and return lines.
Installation of this hose creates a "loop" through the hose and the engine
side of the fuel system.
- Obtain the J 35800-A (2). Make
sure the valve at the bottom of the canister (3) is closed.
- Remove the canister top and add 24 ml (0.8 fl.oz.) Top
Engine Cleaner, GM P/N 1050002 (Canada P/N 992872), to
the canister.
- Fill the remainder of the canister with regular unleaded gasoline
and install the canister top.
- Suspend J 35800-A from a convenient location under the
vehicle.
- Connect the hose from J 35800-A to the service port on
the J 44466-1.
- Open the valve (3) at the bottom of J 35800-A.
- Connect a "shop air" source to the fitting at the top of J 35800-A
and adjust the regulator (1) to 75 psi.
- Lower the vehicle to a convenient height and start the vehicle.
It may be necessary to re-adjust the J 35800-A pressure regulator to
maintain 75 psi.
- Let the vehicle run at idle until the canister is empty and the
vehicle stalls.
- Turn OFF the vehicle ignition switch.
- Raise the vehicle.
- Remove the shop air supply from J 35800-A.
- Depressurize J 35800-A.
- Disconnect J 35800-A from J 44466-1.
- Remove J 44466-1 and J 44466-2 from the vehicle
fuel lines.
- Re-connect the vehicle fuel lines.
- Lower the vehicle.
- Add one (1) ounce of Port Fuel Injector Cleaner, GM P/N 12345104
(Canada GM P/N 10953467), to the vehicle's fuel tank for each gallon
of gasoline estimated to be in the tank. Instruct the customer to add the
remainder of the bottle of Port Fuel Injector Cleaner to the vehicle's fuel
tank at the next fill-up.
- Tighten the fuel tank filler cap.
- Start the engine and check for fuel leaks.
- Clear any Powertrain DTC codes as required.
- Advise the customer to change brands of fuel.
Parts Information
Part Number
| Description
|
1050002
| Top Engine Cleaner
(U.S.)
|
992872
| Top Engine
Cleaner (Canada)
|
12345104
| Port Fuel Injector Cleaner
|
10953467
| Port Fuel Injector Cleaner (Canada)
|
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
| Description
| Labor Time
|
J5645
| Injector, Fuel - Clean
| 0.8
|