Hi Gang, I'm Back!

I was getting a misfire on cylinder 6 (computer code) so did the usual . . . changed plugs, wires, checked all the coils, have a good spark, etc. with no results. So, I went the next step and bought 6 re-manufactured injectors from AutoParts.com. Still no better.

Had the dealer look at it and they believed the injectors were still bad because they were getting misfires, particularly in 5 and 6. 5 was so bad they said the injector stuck open and flooded the cylinder, i'm skeptical that this might have been gas and coolant, not just fuel pumped into the cylinder.

I'm also skeptical and don't believe that the 6 new injectors were as bad as the injectors I replaced with 120,000 miles on the car. What about a leaky head gasket or something in the upper intake?

I also thought about a vaccum leak but I would have thought this would be across more cylinders.

Thanks Lance

97 Pont Bonne
No Supercharger :(

Do a compression test on each cylinder.

Also, check your oil for contanimation from coolant. If coolant is in the oil, get the oil drained ASAP.

For a possible upper intake failure. You want to check your coolant levels in both overflow and radiator.

Are those plug wires possibly touching the O2 sensor wires? That will give you a misfire quick.

What type of plugs and wires on are on the car, how old etc?

What he said.

Just to be a broken record...check these things ASAP!!

Let us know what you find.

Unbelievable. #6 wire was right against the O2 sensor. Pulled it away and runs like a dream.

Why is there such interference that causes the misfires throughout the engine. This sure seems like bad planning to lay out two conflicting devices so close.

Hopefully this holds up and I won't be back (on this post anyway!).

Thanks, Lance

Glad it worked out for you

Even though you have resolved your current problem, as an L36 owner, you need to keep a close watch on your coolant level and read this Techinfo article: http://www.bonnevilleclub.com/forum/...e=article&k=38

Glad it was an easy one.

Well, the problem showed up again briefly this morning, started missing as soon as I pulled out of the driveway. I turned it off and disconnected the battery for 5 minutes thinking it might be an electrical "weird" thing. On restart, it has worked flawlessly again with the check engine light on the next two trips until it reset itself.

I bought an engine scanner and have some freeze data. Please chime in if you have any thoughts/revelations.

Code: P0300 Multiple Misfires
Fuel Sys1 - CL, Using HO2S
Fuel Sys2 - N/A
Calc Load % - 3.5
Coolant (F) - 208
ST FTRM1 (%) - 9.3
LT FTRM1(%) - 16.3
MAP (in.hg) - 19.8
Eng RPM - 753
Veh Speed (MPH) - 3 (really flying huh?)
MAF - (lb/min) - 0.826
ABSLT TPS(%) - 0.0

I'm still wondering if I have a vacuum leak in the manifold. The Manifold Absolute Pressure (MAP above) shows 19.8, but I don't know what a nominal value for this is? Still figuring out what all this new data means.

I plan to keep the scanner in the car to get all the data I can handle.

Thanks in advance for your thoughts, Lance