1999 Subaru Legacy 2.2L AT Wagon

2.5L block, 2.2L single port heads with correct MLS HG for block

Delta 1500 grind

KN filter on the stock cold air intake

 

Problem: Starts OK then stalls after 3 seconds

 

Recent maintenance:

• New battery
• Replaced plugs & wires with new NGK
• New coil pack
• New fuel filter
• New alternator
• I cleaned the MAF with MAF cleaner. Then the problem started

Car had been running good on the road; some minor stumbling between 1000-1200 rpm

 

Problem troubleshooting; What I've tried so far:

1. No CEL
2. Disconnected MAF; would not run
3. New MAF sensor; reset ECM by disconnecting battery for 30 minutes; no luck
4. Disconnected MAF; would not run
5. Disconnected battery over night; no luck
6. Swapped out fuel pump with known good spare
7. Visually checked for vacuum leaks; not that many hoses
8. No CEL

Next:

1. IACV?
2. ECM?  22611 AD66B DY7 80

Edited May 11, 20169 yr by noslliw1

Loose hose on the intake tube. The big one for the IAC usually gets overlooked because it looks like its in the right spot.

 

The hoses from the valve covers that attach on the back/bottom of the tube need to be connected at both ends, and the one next to the PCV hose.

Thanks for the suggestion.

 

On this car (1999)  there is no hose or connection for a hose on the intake tube. There are three that go right into the air box: 2 from the valve covers, and 1 from the big vertical hose that also connects to the PCV. I'm at a complete loss. Starts perfect, then stalls in about 3 seconds.

Sounds like its either getting un-metered air (air leak into intake tube between the MAF and throttle body), or MAF wiring could be damaged,

Or fuel pressure is dropping off after it starts.

 

Check the tube for any cracks, especially between the ripples where it flexes.

If it has the resonator tube that sticks off the side, check where that connects to the main tube. Have seen them break there.

Edited May 15, 20169 yr by Fairtax4me

I wonder if the ECU is shutting down the fuel system for some reason or the security system is involved.

sure there's no hose for the IAC?

 

 

any progress on this?