99 Boneville SSEI "Engine Misfire" , please help if you can

[erinhardesty]

Please help....
My 99 Pontiac Boneville is misfiring, constant. The diagnostic report says "Miscellanous Misfire, Engine Misfire". Spells like gas, really bad. I spend $45, every few days to fill it up and drive only 5 miles to work. I try and excell and it will not go! I step on it, the rpms go all the way up but the car will not excell. Then all of a sudden, it will catch ( I dont know proper term), and I will be flying.
I have recently had spark plugs changed, wires, iginition coil, filters cleaned, catalyst converter replaced, Mass Air Flo Sensor.
The Machanic recently said it was cylinders #2 and #4 that were having the issue.
I them took it to an Exhaust shop and had the Catalyst Converter replaced.
After replaced, for one trip to work.. it ran better than it ever has. Then that evening the problems started to re-occur.
It is running worse than ever, I dont think its safe to be driving it.
I have spent a ton of money on the problem and have yet to had a solution.
If anyone has experienced this or heard of this or solved this, your input would be so very much appreciated?

Thank you

Erin

[willwren]

Please have the car scanned (most auto parts stores do this for free) and report all the codes back to us. Also give us a history of the maintenance performed on the car in the last year.

Please also inspect your oil after a short drive. Pull the dipstick, and describe the consistency and color. Pull the oil fill cap and describe what the oil inside looks like.
Look at your coolant and tell us what color it is.

[erinhardesty]

Will do, I am actually going to call the Pontiac Dealership now to see if I can get in for a diagnostic within the next day or two.

I will definatley take provide the info you have inquiried..

I am so stoked to have come across this website, for my car has been stressin me out for almost a year now.

You guys are a blessing. Thanks, will update shortly.

[harofreak00]

Dealership diagnostic = $100+
Parts store diagnostic = FREE

[erinhardesty]

I am taking my car tomorrow early morning to the pontiac dealership and will post the results once I get to my office.


This has now become exciting! You guys are the best!

My dad originally put new wires on a few months back, when he changed the starter and MAFS. The mechanic who recently looked at it changed the wires, he said they were crossed (however, he mistakenly mixed up some wires when trying to clean the fuel injectors, and same storey on a vehicle of my co-workers).. so I will make sure to have the dealership check them. Spark plug wires? or ignition coil?

thanks again,
E

[willwren]

You have 3 ignition coils, not one. And don't take it to the dealership. Take it to a parts store (NAPA, Autozone, etc) and have it scanned for FREE.

Write the codes down and report them back here.

[erinhardesty]

I was just researching online and came across another member who had an issue recently with a 98 boneville with the engine power, bad gas smell, like it was unused and he provided graphs and so forth.
The outcome I did not see but he was going to check the fuel regulator and was instructed to change the o2 sensor. I will post my codes in the morning however his storey sounds extremely similar. Exept I just had the CAT replaced. Maybe it's bad.
??? Anyone familiar with that post? I wish I had more details but as soon as I hit post a reply I was brought to main log in screen and lost the info. I believe some of you were helping him. Well off to bed.

[willwren]

Let's stick to your codes and your issue. That's where we'll start, and take it in a logical manner from there.