New thread for the L67 Engine fires Issue
There is a rash of these that have happened and would like to see a discussion/comments for newer members. I'll start with the resulting carnage.

Ha there been any word on what is causing these fires? I can tell there was a engine cover on there. I personally never liked the idea of a plastic cover on top of a hot engine. That'* why mine is sitting up on the shelf.

I don't recall all the details except something about oil dripping onto a hot manifold and igniting. There was apparently an investigation and GM launched a recall on a specific group of cars they believed to be at risk. There was much discussion amongst 3.8L Supercharged owners about GM'* exclusion of some cars in the recall. Apparently had nothing to do with the engine cover from what I understand.

I saw somewhere else that the engine cover acted as a heat trap that caused a nylon fuel line that ran near the supercharger to heat beyond its rated temperature range and start sparying fuel onto the hot engine

I have never heard this, not to say it isn't true but I know there was some "speculation" amongst people that this may be the case. I've never heard or seen any recall to this effect.

This is what I'm talking about...

Pontiac and Buick Recall: 207,542 have potential engine fire fears : Product Reviews Net

I have seen a recall addressing this issue.

Alot of speculation for sure, some pointd to the grounding and fuse blocks because the passenger side seems to be affected. I looked up and found the recall Darcy, seems we have the "official" answer. Alot of good info so I'm going to post it here. For some reason the Bonneville wasnt included but we have seen our share of them fried.


Subject: Upcoming Safety Recall 07035
Potential Under hood Fire - 3.8 L Supercharged
Engine

Models: 1997-2003 Buick Regal GS
1997-2003 Pontiac Grand Prix GTP
With 3.8 L V6 Supercharged Engine (VIN1 –
RPO L67) LISTED BELOW

To: All Buick and Pontiac Dealers

Attention: Service Manager, Parts Manager, and
Warranty Administrator

Based on information from the National Highway Traffic Safety Administration (NHTSA) website, the media may report that General Motors will be announcing a safety recall involving certain 1997-2003 model year Buick Regal GS and Pontiac Grand Prix GTP vehicles equipped with a 3.8 L supercharged engine (VIN 1 – RPO L67).

These vehicles may experience an under hood fire. The fires may be caused by drops of engine oil being deposited on the exhaust manifold through hard braking. If the manifold is hot enough and the oil runs below the heat shield, it may ignite into a small flame in and in some instances the fire may spread to the plastic spark plug wire channel. Most cases have occurred five to ten minutes after the vehicle has been turned off.

If a fire occurs, it may cascade through the engine compartment causing vehicle damage and in some cases, the fire may spread to structures where the vehicle was parked.

A total of 207,542 U.*. vehicles are involved. We are currently working with our suppliers to obtain parts required to launch a safety recall in the near future. However, in the interim, a customer advisory letter (see attached) is being sent to all customers of record to inform them of this situation. This letter will also provide three important precautions the customer should take: 1) Do not park the vehicle in a garage, car port or other structure. 2) If a burning odor is detected, the customer should take their vehicle to a dealer for inspection. 3) Customers should use premium fuel (91 octane or higher) as recommended in their vehicle owner'* manual. The customer letter will be mailed on March 13, 2008.

If a customer comes in with this letter or is otherwise concerned about this condition, please use Technical Service Bulletin 08-06-04-019 to service their vehicle. Please note that there are two T labor operations listed. Warranty claims should be submitted using the specific T labor operation depending on the source of the gasket (GM or aftermarket) you install in the vehicle. The use of the two T labor operations may allow GM different options when the recall is officially released. The Technical Service Bulletin 08-06-04-019 is available in SI on March 12, 2008 and is attached for your convenience.

After the repair is complete, the customer will be ableto park their car in their garage, car port or other structure.

A Frequently Asked Question and Answer document has been developed for your reference. This FAQ will help answer any customer concerns. Please see the attached Dealer FAQ'*.

GMVIS information will not be available for this recall until the recall bulletin is released to dealers
************************************************** ***************************************

POTENTIAL QUESTIONS AND ANSWERS
Q1: What vehicles are involved?
A1: All 1997-2003 model year Pontiac Grand Prix GTP and Buick Regal GS vehicles equipped with the 3.8-liter L67 supercharged engine. A total of 207,542 U.*. vehicles are involved.
Q2: What is the condition?
A2: These vehicles may experience an under hood fire. We believe the fire may be caused by drops of engine oil being deposited on the exhaust manifold through hard braking. If the manifold is hot enough and the oil runs below the heat shield, it may ignite into a small flame and in some instances the fire may spread to the plastic spark plug wire channel. Most cases have occurred five to 10 minutes after the vehicle has been turned off.
Q3: What are the consequences of this condition?
A3: Fire may cascade through the engine compartment causing vehicle damage. In some cases, the fire has spread to structures where the vehicles were parked.
Q4: How was this condition discovered?
A4: The National Highway Traffic Safety Administration opened a preliminary evaluation in January 2007 based on 21 customer complaints alleging engine compartment fires after their vehicles were turned off. GM began an extensive investigation.

Q5: Why didn’t GM know about this?
A5: The rate of occurrence was very low, about one in 1,000 vehicles.

Q6: Have there been any injuries or deaths resulting from this condition?
A6: We are aware of five minor injuries and one moderate injury. No fatalities.

Q7: How many fires have there been?
A7: We are aware of 267 fires to date.

Q8: What about property damage?
A8: We are aware of 17 fires involving structure damage.

Q9: What is GM doing to correct this condition?
A9: Due to parts availability, corrective action will occur in two stages. First, a "customer advisory letter" is being sent to each involved customer of record. This letter will explain the situation and provide precautionary measures that a customer can take until their vehicle is repaired. The letter will be mailed on March 13, 2008.
The second stage will be the release of Safety Recall Bulletin #07035 to all Pontiac and Buick dealers. This will occur once an adequate supply of recall parts is available. At that time, all involved customers of record will be notified via a second letter to bring their vehicle in for the required repair.



Q10: If I have one of these vehicles, is it safe to drive?
A10: Yes. Very few of the fires (about 20 percent of the reported cases) have occurred while the vehicle’* engine was running. The rate of occurrence is also very low, about one in 1,000 vehicles.

Q11: Is there anything I can do to prevent a fire after the vehicle is turned off?
A11: No.We believe the fires may be caused by drops of engine oil being deposited on the exhaust manifold through hard braking. For now we are urging customers to avoid parking their vehicles in a garage, car port or other structure and to use premium fuel (91 octane or higher) in their vehicles, as recommended in their owner’* manual. If you smell any kind of burning odor, have the vehicle inspected by a dealership service department.

Q12: The customer advisory letter mentions oil getting on the manifold during hard braking. Is there a problem with the brake system?
A12: No.

Q13: The customer advisory letter mentions premium fuel. Why is this important?
A13: Because the vehicle was designed to run on 91-octane fuel, using lower-octane fuel increases under hood temperatures during operation.

Q14: Are the 1997-2003 Pontiac Bonneville, Buick Park Avenue and Riviera, and Oldsmobile LSS involved or any vehicles with 3.8L engines without superchargers involved?
A14: No, they are not part of this field action.

Q15: Who will pay for the repairs?
A15: Repairs will be made free of charge to customers.
Q16: I heard that there were under hood fires in Chevrolet Tahoe’*. Is this the same issue?
A16: No. NHTSA opened a preliminary evaluation in February based on two customer complaints of under hood fires in 2007 model year Tahoe’*. We are cooperating with the agency but we have found no trend suggesting a recurring problem. The Tahoes and GMC Yukons being investigated are of a different architecture and were produced much later than the Pontiac Grand Prix GTP and Buick Regal GS.
Q17: Until Safety Recall Bulletin #07035 is released, what can dealers do to satisfy customers who may express a concern, or request an immediate repair?
A17: Until GM parts are available for this recall and Safety Recall Bulletin #07035 is released, GM has provided dealers with Technical Service Bulletin #08-06-04- 019.The bulletin provides repair instructions for those customers who have an immediate concern with their 1997-2003 model year Pontiac Grand Prix or Buick Regal vehicle equipped with the 3.8-liter L67 supercharged engine.
Q18: When will the GM Vehicle Inquiry System (GMVIS) be loaded?
A18: Involved VINs can not be loaded to GMVIS until Safety Recall Bulletin #07035 is released.
Q19: After completing Technical Service Bulletin #08-06-04-019, is it safe for customers to utilize parking structures?
A19: Yes.
Q20: If the parts required to perform Technical Service Bulletin #08-06-04-019are in short supply, can aftermarket parts be used to complete the repair?
A20: GM approved parts are preferred, however, for the immediate repair outlined in Technical Service Bulletin #08-06-04-019, locally obtained aftermarket parts may be used. Dealers should be sure to submit a warranty claim with the correct "T" labor operation when using aftermarket gaskets. Specific details are provided in the technical service bulletin.
Q21: If a customer had the front engine rocker cover gasket recently replaced on their 1997-2003 model year Pontiac Grand Prix or Buick Regal vehicle equipped with the 3.8-liter L67 supercharged engine, should dealers replace the front rocker cover gasket again?
A21: If the front rocker cover gasket was replaced by a General Motors dealer using GM Part #24503937, then the gasket does not need to be replaced again. The technician should complete the technical service bulletin repair by removing the spark plug channel retainer and install the spark plug retainers as outlined in the procedure. If the customer paid for the gasket replacement, there will be reimbursement instructions provided when the recall is released.
Q22: Why does the procedure only call for the replacement of the front engine rocker cover gasket and not both?
A22: GM’* investigation has not shown a need to replace the rear gasket.
Q23: An owner of an involved vehicle has concerns and requested immediate assistance. Upon inspection it is noted during the replacement of the front rocker cover gasket that the rear engine rocker cover gasket shows signs of oil seepage - should the rear gasket be replaced as well?
A23: Replacement of the rear engine rocker cover gasket is not part of the service bulletin repair procedure. Customers may wish to have the rear cover gasket repaired as part of customer paid vehicle maintenance.
Q24: Why aren’t 1997-2003 model year Pontiac Grand Prix and Buick Regal vehicles with the L36 non-supercharged engine involved in this safety recall?
A24: GM’* Investigation has shown that the supercharged engine has unique operating characteristics not present with the L36 non-supercharged engine. Specifically, the L67 supercharged engine has a significantly higher normal under hood operating temperature.
Q25: Why are two "T" labor operations listed in Technical Service Bulletin #08-06-04- 019?
A25: As detailed in the technical service bulletin, warranty claims should be submitted using the specific "T" labor operation depending on the source of the gasket used by the dealership. The use of the two "T" labor operations allows GM different options when Safety Recall Bulletin #07035 is released. __________________

Well my two cents worth....oil would need to be heated between the low end for synthetic blends at 390F to 500F for oils like Amsoil before the oil ignited. It'* not impossible to ignite oil, its just stubborn and needs the maximum heat and the right open flame ignition source to do so.

I've investigated many auto fires over my career and engine compartment fires are usually caused by a main fuse fault, gasoline delivery system failure or mechanical failure that result in back pressure/fire and then subsequent ignition of insulation, air filters and plastic pieces. Of course there have been those attributed to arson.

Inusrance Industries Investigators and most municipal fire investigators have decided to not investigate for cause of auto fires, but to rule out fires as arson.

Whether an electrical problem is the case or not, I don't recall there ever being an "official" acknowledgement of this (as far as the fuse block or ground). I visited a lot of forums and read a lot of peoples theories. I guess my problem with this type of discussion is that too many people believe they are professional investigators who have it all figured out. Members on some forums were making rather far fetched claims as to what caused these fires.

At the end of the day, I don't believe there are very many people who truly have all the facts available, nor the education as investigators to really know what they're talking about. IMO, there is way too much speculation in forums amongst amateurs (of which I also rank myself). I believe that instead of spreading questionable opinions and fear, that we let the proper investigations take place and derive the true cause of some of these problems.

Until I see evidence that the recall doesn't solve this problem, I'll sleep satisfied that the problem has been found.

Do manifold temps under a heat shield reaches those temps. The former admins here were, in their usual "we know all" way insisting it was electrical. But I really fail to see that scenario. An electrical block on the fender frying to a crispy ashes doesnt seem like it would trigger a fuel ignition. Maybe there is a combination of issues at work here?

I have a hard to believing it'* electrical only. There needs to be some other fuel at play, leaking oil or fuel. A electrical started fire should blow a fuse, unless someone using a over sized fuse. I'm leaving towards leaking oil of gas, then a ground arch from the spark plug wires. Another great argument to keep your engine bay clean.