Strange Happenings

[MMGT1]

Have a very strange issue going on. Try to give you a little info here.

Daughter born a couple of weeks ago, went to bring her home from hospital. Car sputters and looses all power(Blown Coil Pack). Replaced all three.
Car seems good. Then car sat for a couple of weeks.(Until a couple of days ago) Drove on highway, and when I got off the highway the car looses idle, sinks to almost stalling, have to keep tapping gas to keep it going. See that 02 readings have dropped to almost nothing. Then, after a few seconds, the car will drive and idle fine????????? This one has me. Then last night drove it again and the 02 readings were dropping and staying down on the highway for a couple of seconds, then kicking back in again. Same issue when exiting the highway.(Stopping)

Anyone had something like this? Let me know if you need a scan of this(I haven had the scanner in the car for a while, but looks like it will be easy to get a scan, but I also don't want to damage the engine) I can get a scan and tune posted if anyone needs.

Paul

[MMGT1]

Just to add, would the MAF delta airflow settings have anything to do with this?

http://www.hptuners.com/forum/attach...5&d=1182112824

This has the tables as they are set now.
Here is the stock one:
http://www.hptuners.com/forum/attach...4&d=1182108509

[Russ K]

I never had the change the Maf Delta Airflow tables from stock. Sounds like the fuel pump is failing.
Tape a fuel pressure gauge to the windshield, and go for a test drive.

Russ Kemp

[MMGT1]

Attachment 10935

Attachment 10936

Here is my tune and scan if you would like to see what I mean. At frame 17637 to 17891 might give you an idea of what's happening?

I'm going to find someone with a fuel gage that I can use to try what you are sugggesting as well Russ. Thanks for your insight.

Paul

[Russ K]

The fuel trims are good, so that rules out a fuel pump problem. But I see the DFCO enabling, as the spark advance drops to 15*,
the fuel trims go to zero, and the O2 mv drop.

Did you make any changes to the Deceleration Enleanment tables?

Russ Kemp

[MMGT1]

DFCO had been adjusted quite a while ago(year or more), but, put them back to stock and drove car today and looks like it might be the problem. Need to drive it a bit to see, but looks good right now. Drove it for about 45min today. Really strange that this would come up now and not a year ago though? IDK...gremlins maybe??hahahaah

I'll get the lap top connected online after school tonight and upload the scan and tune from today for you to peek at.

Thanks Russ,

Paul

[MMGT1]

Just had a brain fart..........do you think the addition of headers might have made this jump to the forefront?