98 3.9 auto

Had idle issues awhile back, replaced the IAC and fixed that issue.

Went to drive the truck yesterday after sitting overnight. Truck started fine, idled fine for about a minute, pulled out, 100 feet down the street truck dies.

Finally started after about (5) minutes of ON/OFF cranking. Drove fine after that. No stalling at all.

The truck did this before I replaced the IAC, but always started right back up.

What do I need to check out ?


TIA

 

see if any codes (use a scan tool) has it only done it once? has it been wet lately? might just be a one time thing from moisture where it shouldn't have been, really hard to say as almost anything could cause it including computer

 

Actually, it did throw a CEL a few days before this happened.

Took it to AutoZone for a code read. Got P0420.... P0420 Code: Catalyst System Efficiency Below Threshold (Bank 1).

My truck does NOT have catalytic converter. I wasn't on the truck when I bought it (6) months ago either. I have no idea when or why a PO removed it. So why the code now ??

I should mention, this truck rarely gets driven very much. It's only really used for hauling stuff around. Maybe 1,000 miles on it the past (6) months. That still wouldn't explain the stalling out issue.

I'm reading threads about fuel pressure issues. I'm wondering if the fuel pressure regulator is on it's last legs. ???

The truck has either 152k or 252k miles on it. Mileage on the Title was screwed up in the past. ?? Either way, the truck runs great otherwise.

 

code is from it being removed (o2 sensor sees something wrong) sitting would allow dirt and water to build up (worst thing that you can do to a vehicle is let it sit)

 

The CEL just came on a few days ago. The converter has been gone long before that. The CEL was not on when I bought the truck (6) months ago.

The truck gets driven at least once a week for at least (10) miles.

How do I verify if the fuel pressure regulator may or may not be an issue ?

 

To test the fuel pressure you can connect a gauge to the fuel rail. It has schraeder fittings for just such a purpose.

 

What PSI range should it be at when idling ?

 

49 psi. It doesn't matter if idling or at speed.

 

this. Mine is usually 43. Really, anything over 40 across all RPM is good.

 

Thanks guys!