: Question on Exhasut smoke/Chemical agent repair

05-04-07, 01:11 PM
Long story kinda short. Bought 1996 caddy, 121k miles, after bought, white/blue some out of exhaust. Open oil cap to put in oil, smoke coming out. Take to shop. Replaced fuel filter, replaced spark plugs and wires, cleaned EGR vavle. After driving home, smoke appeard on free with accelerating and decelerating. Also smokes when first start in morning, and still have smoke out of engine when lifting oil cap.

Just brought back to shop. Now they say bad rings(not headgasket because not over heating and no loss of coolant.) They are going to put some chemical in engine, have to remove plugs and wires, cost of 400 more bucks, saying Cadillac says this is fix for bad rings. Any thoughts?????? I just want this damn smoke from exhaust gone. I have almost spent on repairs what I paid for car. Thank you..


05-04-07, 01:47 PM
I just want this damn smoke from exhaust gone. I have almost spent on repairs what I paid for car.

Get used to it. I ended up spending about 3 times as much on repairs as i paid for the car. A little bit of smoke out when you take off the oil fill cap i believe is pretty normal. I' ve never heard of a chemical that can help bad o-rings. You may want to get a 2nd opinion from a diff. shop. Of course i could be completely wrong, but some one will corrct me im sure.

05-04-07, 02:01 PM
Thanks for the respond. I also found this....


The information in the article applies only to the 1996-1999 Cadillac DeVille, Eldorado and Seville.

One of the major reasons for oil consumption is combustion deposits that build up on the pistons and rings and cause them to stick in the piston. Stuck rings cannot effectively wipe the oil off the cylinder walls, and the oil will burn in the combustion process.

To deal with an oil consumption condition, begin by following the guidelines in bulletin 01-06-01-011:
- verify general oil consumption concern
- repair oil leaks
- verify that no specific cylinder(s) is burning oil as defined by
oil on the back side of the intake valves or oil on the spark plug.

Then, if necessary perform a new ring-cleaning procedure. The bulletin for this procedure is expected in February. Technical Assistance has a faxable version of the cleaning procedure that can
be sent out until the bulletin is available.

You will also need the J-45076 induction/evacuation tool, which is available from Kent-Moore.

TIP: This cleaning process is not approved for any other repairs on any other engine families at this time.

TIP: Do not confuse this cleaning process with a repair for the cold start knock noise that some 2000-01 Northstar engines experience. While the new ring-cleaning procedure will also clean the combustion camber deposits, Top Engine cleaner is just as effective for knock
concerns. Follow bulletin 99-06-01-101A for the cold start knock condition.

The multi-step procedure is detailed in the upcoming bulletin. Briefly; you will use the components in the J-45076 tool kit to install Piston and Ring Cleaner 12378549 (88901334 in Canada) through
the spark plug holes into warm cylinders. After a 2-hour soak, you will vacuum the cleaner from the engine and change the oil. Then you will apply Induction Cleaner 12378552 (88901336 in Canada) to the EGR and throttle body using components of the J-45076 tool kit.

Finally you will road test the vehicle for 20 minutes, then change the engine oil again, replace the oil filter and reset the oil life system.

After the ring cleaning process is complete, perform a post oil consumption test. When an oil consumption test is performed, it is critical that the crankcase not be over-filled. Extra oil will be
scavenged out of the crankcase in a short amount of time, giving the impression of a false oil consumption concern.

The crank case capacity of 4.6 L engines for the models years listed is 7-1/2 quarts (7.1L) with a filter change.

An engineering team is studying the other cause of oil consumption on this engine. As recommendations from this group become available, the information will be made available.

The labor operation for this process is J1952 and it provides 3.2 hours. Do not try to short-cut the process. If the cleaning is not done properly, the vehicle may not be repaired.
[end article]

The bulletin they talk about being released in February still hasn't been released from TAC: #A001846D Supplement to 01-06-01-011 4.6L LD8 , L37 ENGINE OIL CONSUMPTION - CYLINDER DIAGNOSIS DTC GUIDE INTAKE LEAK MISFIRE MPG PISTON PLUG A001846D SUPERSEDES A001846C A001846B A001846A A001846.

05-04-07, 05:26 PM
Before you go through all this work and expense, go to the top left of this page. Click on TECHNICAL ARCHIVES and read up on "oil consumption". Try the WOT procedure first.

05-10-07, 11:56 AM
Just got back from the shop, paid another 400 bucks on the caddy. Still has smoke coming from engine when the oil cap is taken off, like something is on fire. Still smokes from exhaust when giving it gas and letting off gas on freeway. mechanic said if this does not work, I probably have bad rings, and nobody will fix that. I have spent as much on this car trying to fix this than I paid for car. Does everyone agree I have bad rings, based on this info. No current codes other than an AC code. Ranger, any thoughts> WOT did not help.

05-10-07, 06:33 PM
Bad rings on a Northstar are pretty rare, but if it is smoking that bad and it is the rings a compression test should reveal it. Was that done? If so, what were the compression readings?

I wonder if the rings are not just carboned so bad that it is going to take a lot of WOT or a decarbon procedure mentioned above.

05-10-07, 09:58 PM
With in the next year a new TSB will be out. The cleaner damages the metal engine parts including the bearings. GM has a new product and will release the new procedure.
I am a Caddy tech

05-10-07, 10:11 PM

05-10-07, 10:21 PM
So, is the General responsible for replacing engines damaged by the piston/ring cleaner that was mandated by the TSB?

05-10-07, 10:31 PM
You'd have to PROVE that your engine was damaged by this procedure. The General is not going to admit to it and I am sure that the new TSB will be written by a lawyer so as to be sure it is not incriminating in any way.

05-10-07, 10:57 PM
Yes, that sounds right.

05-10-07, 11:36 PM
Let me tell you, after opening up the motor on my 98, I can't see the rings being bad. You can still see the milling marks on the cylinder wall and there is NO lip from wear at ALL. It looks like a brand new engine inside. It has 118K on it too.

05-10-07, 11:46 PM
It is not mandated

05-10-07, 11:54 PM
Subject: Higher Than Expected Oil Consumption (Clean Piston Rings) #02-06-01-009C - (10/23/2003)

Models: 1996-2000 Cadillac Concours

1996-2002 Cadillac Eldorado

1996-2003 Cadillac DeVille, Seville

with 4.6L Engine (VINs Y, 9 -- RPOs LD8, L37)


This bulletin is being revised to add parts information. Please discard Corporate Bulletin Number 02-06-01-009B (Section 06 - Engine).


VIN Breakpoints
Model Year
VIN Breakpoint

All Above

Prior to 3U213641

Prior to 3U215818

Some customers may comment on higher than expected oil consumption. The typical customer with this condition comments on consumption in the range of 0.946L (1 qt) of oil used in 1600-2250 km (1000-1400 mi) of operation. The oil consumption rate and possible oil consumption areas, as per Corporate Bulletin #01-06-01-011 dated March, 2001, should be verified prior to performing the ring cleaning procedure below. The standard for acceptable oil economy and the method for determining oil economy are outlined in Corporate Bulletin #01-06-01-011.

The following text is referenced from Corporate Bulletin #01-06-01-011 for your convenience.

Oil Consumption:

The accepted rate of oil consumption for engines used in the vehicles referenced is 0.946L (1 qt) in 3200 km (2000 mi). This rate only applies to personal use vehicles, under warranty, maintained in accordance with the appropriate maintenance schedule, with less than 58,000 km (36,000 mi), or 80,450 km (50,000 mi) for Cadillac, driven at legal speeds in an unloaded (for trucks) condition.

Although there are several reasons for less than expected oil economy described in Corporate Bulletin #01-06-01-011, one area not covered is reduced sealing ability of the rings. Through normal usage, combustion chamber deposits may build up to the point that the movement of the rings could become restricted and prevent the rings from wiping all of the oil off the cylinder walls and allowing it to be burned in the combustion process.

A new ring cleaning process has been developed to restore the function of the rings. Once the possible oil consumption areas in Corporate Bulletin #01-06-01-011 have been eliminated, this cleaning process should be performed. If the oil economy has not improved to 0.946L (1 qt) in 3200 km (2000 mi) after cleaning, it may be necessary to replace the piston rings. Be sure to install the second compression ring notch side down. If the vehicle is a 2000 to 2003 with an oil consumption concern with less than 25,000 miles on the vehicle, then skip the cleaning process and install the new rings.

Important: It is critical in this cleaning process that the piston and ring cleaner remain in the cylinders for a minimum of two hours to fully clean the components. The cleaner solution must be removed before three hours. Additional soak time does not increase the effectiveness of this process. If solution with the dissolved deposits remains in the cylinder too long, it will soak back into the rings and cause them to stick again. If this happens, the oil economy will be reduced even further.

An oil economy test should be performed after the cleaning process is completed. Before starting this test, the full oil level on the dip stick should be noted and shown to the customer. The correct oil fill is 7.1 L (7 qts) with a filter. The dipstick should not be read for at least 15 minutes after the engine has been shut off for an accurate reading. Typically, the oil level shown on the dipstick is in the second or third section above the add mark. If the indicated oil level is at the MAX mark, there is approximately 0.47 L ( qt) too much in the system and it will be scavenged by the PCV system quickly. When performing this test, the most accurate results may be obtained by having the customer drive the vehicle until the CHECK OIL LEVEL message appears and then returning the vehicle to the dealership to determine the oil economy. No damage will be done to the engine by operating it until the Check Engine Oil Level message is displayed. There is 4.7 L (5 qts) of oil still in the system.

Field feedback has indicated that vehicles that have been operating at a high consumption rate (0.946L (1 quart) of oil in 1600 km (1000 mi) or less) for greater than 32,000 km (20,000 mi) may need a second application of the piston and ring cleaner to adequately clean the rings. If a second application of piston and ring cleaner is necessary, it can be done immediately after vacuuming out the first application.

Cleaning Procedure
Place the vehicle gear range selector in Park.
Start the engine. Raise the engine speed to 2000 RPM.
Warm the engine coolant temperature to a minimum of 93 C (200 F).
Shut the engine off.
Remove the ignition coils and module for access when using the evacuation tool.
Remove the spark plugs and ensure that none of the pistons are at TDC.
Install the induction hose manifold, J 45076-24, (4 hoses) into the front bank of spark plug holes. Press each hose into the spark plug opening to retain the hose.
Important: Remove the original hose from the canister and install the hose provided in the J 45076 kit.

Connect the CPFI canister, J 35800, to the induction manifold.
Pour the first can of Piston and Ring Cleaner, P/N 12378549 (in Canada, P/N 88901334), included in kit P/N 12378545 (in Canada, P/N 88901333) into the canister, J 35800-A.
Pressurize the canister to 103 kPa (15 psi).
Important: If the hose pops out while inducing cleaner into the cylinder, simply reinsert the hose back into the hole.

Open the valve on the canister hose to induce the first can of Piston and Ring Cleaner into the front bank of cylinders.
Depressurize the canister (use the pressure regulator to release pressure, then close the canister valve) and remove it from the 4 hose manifold.
Move the 4 hose manifold to the rear bank of cylinders.
Pour the second can of Piston and Ring Cleaner into the canister and reconnect the canister to the manifold.
Pressurize the canister to 103 kPa (15 psi).
Open the valve on the canister hose to induce second can of Piston and Ring Cleaner into the back bank of cylinders.
When the canister is empty, depressurize it (use the pressure regulator to release the pressure, then close the canister valve) and disconnect the canister, J 5800-A, from the manifold. Remove the induction hose manifold assembly from the engine.
Important: The piston and ring cleaner solution must remain in the cylinder for a minimum of two hours. If the solution is removed in less than two hours, the cleaning process will not be 100% effective and may not correct the condition. Additionally, do not allow the cleaning solution to remain in the engine more than three hours. If the dissolved solution is left in the cylinders more than three hours, it will soak back into the rings and cause the rings to stick again.

Allow the chemical to remain in the engine cylinders a minimum of two hours.
Important: While evacuating the cleaning solution from each cylinder, manipulate the hose around the circumference of the cylinder to ensure all fluid is removed.

After the two hour soak period, connect the evacuation pump assembly, J 45076-2, to shop air and evacuate the piston and ring cleaner solution from each cylinder through the spark plug hole.
Properly dispose of used cleaning solution by putting it into waste oil.
Important: If a second application of piston and ring cleaner is necessary (see Correction above), repeat Steps 7 through 20.

Change the engine oil. The filter will be changed after the road test.
Add 6.6 L (7 qts) of oil and inspect for visible oil leaks.
Place shop rags over all plug holes and intermittently bump over engine to ensure no hydraulic lock is present.
Crank the engine continuously for 20 seconds.
Remove the rags and reinstall the spark plugs.
Reinstall the ignition coil module.
Remove the mass air flow (MAF) sensor and the air cleaner for access to the throttle body.
Use the aerosol Throttle Body Cleaner, P/N 12378550 (in Canada, P/N 88901335), included in kit P/N 12378545 (in Canada, P/N 88901333) and manually clean the throttle body and the idle air control (IAC).
Remove the exhaust gas recirculation (EGR) valve.
Install EGR Cleaner adapter J 45076-45 and throttle body cleaner adapter. For 1996-1999 models use the J 45076-46 throttle body adapter. For 2000-2003 models use the J 45076-55 throttle body adapter. The J 45076-55 is held in place by the air intake duct.
Remove the position crankcase ventilation (PCV) valve. Inspect for proper operation and clean or replace as necessary.
Connect vehicle exhaust pipes to shop ventilation system.
Pour induction cleaner, P/N 12378552 (in Canada, P/N 88901336), included in kit P/N 12378545 (in Canada, P/N 88901333 ) into the CPFI canister, J 35800-A, and connect the canister to the EGR Cleaner Adapter and Throttle Body Cleaner Adapter, J 46076-46.
Pressurize the canister to 138 kPa (20 psi).
Start the engine. Connect the Tech 2 and raise the engine RPM to 1100 RPM with Tech 2 at F3- RPM Output.
Open the valve on the canister to induce the induction cleaner through the MAF and the EGR Adapter. Regulate the air pressure to obtain a good fan pattern of the solution into the throttle body, but not so much that the fluid overflows out of the throttle body.
When the canister has been emptied (use the pressure regulator to release pressure then close the canister valve), exit the Tech 2 F-3 function to reduce the engine RPM to normal idle speed.
Turn the ignition to Off.
Remove the EGR Cleaner Adapter and the Throttle Body Cleaner Adapter, J 45076-45 and J 45076-46.
Reinstall the EGR valve, MAF Sensor and air cleaner.
Use the Tech 2 to clear any DTCs set during the cleaning procedure. Disconnect Tech 2.
Notice: Start the vehicle and gradually increase the RPM to 2000 RPM in park. Engine damage could result from any fluid left on top of the piston if RPM is increased too quickly.

Maintain the RPM at 2000 for 1-3 minutes. Then promptly road test the vehicle for a minimum of 20 minutes in the third gear range. Include several short, wide open throttle bursts.
After the road test, allow the engine to idle for one minute with the A/C off and the gear selector in the PARK position.
Connect the Tech 2 and inspect and clear any codes from the road test. An EGR pintle code may set from debris binding the valve. Clean the EGR valve, if necessary.
Turn the ignition to Off. Disconnect the Tech 2.
Change the engine oil and filter.
Verify the oil level.
Reset the Engine Oil Life monitor.
Important: It is not necessary to deglaze the cylinder walls when installing the new rings. The new rings can be installed in the cylinder bore as they are. The bores should be inspected for any cracks or damage before reassembly.

If the post oil consumption test results for a 2000 to 2003 vehicle indicate the oil economy is still less than 0.946L (1 qt) in 3200 km (2000 mi) on vehicles still in the warranty period, then the piston rings should be replaced. The new part number for the piston rings is 89017413. Be sure to install the second compression ring notch side down. Rings with the increased tension and other improvements are now available for the 1996 to 1999 vehicles. That ring package is P/N 89017431.

Important: There is a new head bolt torque angle specification that should be used when installing the head bolts. The new spec is 175 degrees total torque angle (the previous specification was 190 total degrees). The 15 degree reduction should be subtracted from the final pass. The final pass would be 45 degrees instead of 60 degrees. This new specification will reduce the possibility of head bolt thread damage and localized stresses, but still provide the necessary clamp load.

Parts Information
Part Number




Kit, Engine Cleaner

12378549 (U.S.)

88901334 (Canada)
Piston and Ring Cleaner (for second application)
1 (if req'd)

Gasket, EGR Mounting

Valve, PCV
1 as req'd

Piston Ring Kit 2000 to 2003 Model Years
8 as req'd

Piston Ring Kit 1996 to 1999 Model Years
8 as req'd

Parts are currently available from GMSPO.

oil build up cause KNOCK
Subject: Engine Cold/Knock/Tick Noise (Replace Pistons) #03-06-01-025 - (09/02/2003)

Models: 2000-2002 Cadillac Eldorado

2000-2003 Cadillac DeVille, Seville

with 4.6L Engine (VINs Y, 9 -- RPOs LD8, L37)


Built Prior to the Following VIN Breakpoints:

VIN Breakpoint



Important: Implementation of this service bulletin by "GM of Canada" dealers requires prior District Service Manager approval.

Some customers may comment about a tick/knock noise, sometimes described as an upper engine ticking noise or a deep low knock that sounds similar to a main bearing knock. This noise is more often heard during engine start up after a long cold soak condition and may or may not diminish as the engine reaches normal operating temperature. The knock may appear to be the loudest at the exhaust manifolds on either side or both. This noise does not change when disconnecting spark plug wires, or individually disabling the fuel injectors. As a general rule, the source of this noise cannot be determined.

The source of this noise may be carbon deposits in the engine combustion chambers.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Install service piston, P/N 89017438, with rings, P/N 89017413. Follow installation instructions in the Service Manual.

Parts Information
Part Number

Piston, Service (includes pins and clips)

Rings, Piston

Bolts, Cylinder Head

05-11-07, 12:06 AM
Subject: Knocking Noises Or Excessive Oil Consumption - keywords carbon cold piston valve zmax #PIP3951 - (10/19/2006)

Models: 1996-2003 Cadillac Concours, Seville, Deville, Eldorado

with LD8 or L37 4.6L V8 engine.


The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Some customers may comment of a knocking noise from the engine, especially after sitting overnight, or of excess oil consumption.

The cause may be excess carbon build-up on the engine pistons. For vehicles NOT covered under the new vehicle warranty, before attempting other repairs, a product called zMax may be of benefit in improving these conditions. Follow the directions on the package when using zMax. Engines with heavy carbon deposits may benefit from more than one treatment with zMax. Treatment with zMax at each oil change may also be of benefit. The zMax website (www.zmax.com) has a locator for retailers selling zMax. We believe these sources and their products to be reliable. There may be additional manufacturers of such products. General Motors does not endorse, indicate any preference for or assume any responsibility for the products or equipment from these firms or for any such items which may be available from other sources.

Please follow this diagnostic or repair 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.

05-14-07, 07:19 AM
Ranger. I tried another WOT, and this time had smoke even coming in through the vents, and the oil light came on. I just had the oil changed. I am at a loss.

05-14-07, 04:05 PM
Smoke indicates that the oil is burning somewhere and the oil light means low pressure. Combined, maybe an external oil leak? See where the smoke is coming from. Check the oil cooler lines & oil filter adapter

11-08-10, 06:00 PM
see this post (and the discussion that prompted it) for some more info about that PIP and zMax