V70 2.5 1998 Starts but doesn't run

belg · Post by **belg** » 07 Nov 2016, 10:47

Our volvo does want to run unfortunately. It does start, motor turns, seems to run, and after 2 sec it dies. When you try to give some gas it dies immediately. We do get spark, and there is enough pressure on the fuel rail. We did replace the immobiliser ring, and tried to start with the spare key.

What could it be?

Here is a link to a video where we try to start the vehicle:

Post by **misha** » 07 Nov 2016, 15:31

Bad transponder(chip) in the key?
Immobiliser kicked in....that's for sure.
Does that car have Lpg system installed?

belg · Post by **belg** » 07 Nov 2016, 15:48

We tried the spare key, so it would be strange if both transponder key's are bad.

Yes the car has a LPG system installed.

Post by **misha** » 07 Nov 2016, 17:13

Are you sure that second key is chipped?It could be just a regular spare key for opening door locks.
You're right....there is almost no possibility that both keys are bad.

Then....immobiliser ecu maybe.When car starts and run for 2 seconds then dies it's classic symptom of immobiliser kicking in.
When that happens...is red light in the center of dashboard by the windshield on or blinking?
What alarm system car have....original Volvo guard or aftermarket.
Is that Venturi LPG system.....sequential systems don't need that discharge plate(detonation discharge plate) on air filter housing?!

belg · Post by **belg** » 15 Nov 2016, 10:34

Reinstalling the immobiliser ring seemed to have solved the issue. After a few tries and short runs we have an other problem. Now the motor doesnt start anymore, not even close. Normally when you turn the key in the second position you'll hear the fuel pump giving one pulse to start. Now the pump pulses first 7 times in a row, and then with a pause of a few second between each pulse. When I try to start the car, I here the starter motor turn, but there is no spark.

Does anyone have an idea?

Post by **misha** » 15 Nov 2016, 13:54

Check MAIN fuel injection relay(the grey one) on cooling fan carrier and fuel pump relay.
You didn't answered about LPG system....is it venturi or sequential?

belg · Post by **belg** » 15 Nov 2016, 23:46

It is a Sequential system.

Post by **misha** » 16 Nov 2016, 16:52

Hmmm...WHY you have a detonation flap installed on your airbox?It's not needed on sequential system.
It is needed ONLY on Venturi and Lambda control LPG systems as a precaution measure.

Check those relays i mentioned in mine previous post.

belg · Post by **belg** » 16 Nov 2016, 17:36

I don't know why the detonation flap is installed, it was already there when I bought the car. I checked and jumped the fuel pump relay "103", no problem with that. I'll check the one above the fan.