1998 S70 starts but won't runs

[precopster]

Did you replace the fuel filter when the pump was replaced?

What symptoms led you to replace the pump? Was there low pressure at the fuel rail? Can you get hold of a fuel pressure guage?

[jderevj]

Did you ever figure out what’s wrong to keep your car running?
I’m having the same problem.
John

[GaryT]

Have been playing around with a lot of things on the car and have some further info. In response to a couple of the questions raised:

1. Naturally aspirated
2. Fuel filter was changed recently anyway so I didn't bother changing it again
3. I replaced the fuel pump as a "just in case" - had a working one from a previous S70 so thought I would give it a go as the symptoms were consistent with last time I had a fuel pump fail.

Got a hold of some injector test lights yesterday. When starting the injectors fire a couple of times and then stop. My thinking at this stage is it would appear the immobiliser function is in some way responsible - for some reason it decides that the key in the ignition isn't the right one so shuts off the injectors. I have taken out the antenna ring around the ignition key and checked connections and stuff and tired jiggling it around when starting the car to see if some of the pins are loose and not contacting properly but no success.

Is there something in the immobiliser circuitry that fails that I need to be looking to replace?

[FLXC90]

Try disconnecting the battery, discharging system, reconnecting, lock then unlock doors in case your alarm relay is acting strangely.

[GaryT]

Yep, did all the disconnect, discharge, lock and unlock stuff.
Installed a new immobiliser antenna ring on the ignition today and no difference.

Is there an immobiliser module somewhere that may need replacing?

[erikv11]

Did you see this post, where one suspect is electrical gremlins?

https://www.matthewsvolvosite.com/forums ... =1&t=67686

How are the cables from the battery? The one to the main fuse box is especially problematic in the x70 cars.

[FLXC90]

oops

[Azik09]

The problem is in immobilizer, and you have poor chances to solve it without diagnostic equipment.
Immo module located on the left side of steering column, but replacement of it will no have any effect until immo module is correctly programmed. Engine control unit, immo and transponder (small chip) inside ignition key are interrelated.
Antenna ring is just a wire coil and need not to be programmed, but I know at least two types of it. They have different resistance and are not interchangeable.
Antenna ring have 4 in-lined pins. Two outer are from illuminating lamp, two inner are from coil. Measure resistance between 2 inner pins of both antennas (old and replaced) and post here.