1997 V70 EU immobilizer test, no start

oldvolvos · Post by **oldvolvos** » 02 Dec 2020, 07:01

OK, I'll continue this thread then.
I have now removed the fuel rail and put a small cup under each injector, and run the engine for like 15s. The amount of fuel in each cup looked to be similar. I had an idea one or two of the injectors were faulty and sprayed too much gas, but this does not seem to be the case. Also, none of the sparkplugs I have removed at various stages of this investigation has been wet.
Still, the car runs if the fuel pump is only on intermittently. I am thinking there is a fault with a sensor for the fuel pressure or something like that, which shuts down the fuel injection completely. Then again, I can't understand how this would work. Too much fuel I would understand, but how could something be built to shut down totally?
But as there is no fuel on the plugs, and the engine stalls in the very split second when it starts, it does look like a total shutdown.

I have loosened the connections to the injectors and sprayed them with electronic lubricant, and when I had them loose previously they looked like they were all squirting.
Previously, I said the engine did not react to starting gas, but if I do the thing with taking out the relay, it does.
I disconnected one of the vacuum hoses, and the engine still ran when I did the relay trick.

I have ordered an ODB reader, so in a few days I can get the error codes.

Meanwhile, any ideas would be appreciated.
cheers

Post by **abscate** » 02 Dec 2020, 10:24

Retitled to reflect troubleshooting

oldvolvos · Post by **oldvolvos** » 07 Dec 2020, 09:34

So, I got my error code reader (an iCarsoft i906) and read the codes. Apart from misfiring on all cylinders, which I already knew, it gave me this; P0172 system too rich Bank 1, P0103 Mass or volume air flow A circuit high. Apparently, this indicates some kind of fault with one of the sensors for air flow.

Now comes the funny part; I erased the codes and started the car. It ran perfectly for 30s and then I turned it off. I had sort of expected something like this, because I read somewhere that erasing the codes might sometimes also erase the problem, at least temporarily. Tomorrow I will do a test run and see what its like when the engine is hot, and read the codes again.

Post by **misha** » 07 Dec 2020, 11:54

For immo box and all other modules in the car you will need a volvo scan tool at least vol-fcr.

That universal scan tool you bought will read engine codes only.

Try to start the car with MAF sensor disconnected(disconnect it's connector) and see will it run without it.

oldvolvos · Post by **oldvolvos** » 10 Dec 2020, 01:28

Final (?) post on this subject.
I bought a used MAF (from a SAAB) and now the car runs. If I encounter any further problems on longer runs, I will post about that on this thread. Also, its time for the annual inspection, and it will be interesting to see whether CO2 levels etc are OK.
Apparently, the car could be started with the faulty MAF when it was cold, but as I always pre-heat the engine I did not notice this important information.
So, a very simple problem, which could have been solved in five minutes if I had had the code reader when I started. Well, at least I have learned a lot.
Thanks everyone who posted answers.
cheers

Post by **misha** » 10 Dec 2020, 03:00

If you want to solve problem properly...you will need
Bosch 0 280 217 107 MAF sensor.
Buy a used one at least.
The one u use from a Saab may be working now but your fuel trims will not be correct for your car and engine performance will be reduced and soon...you will be chasing your tail again.

Post by **abscate** » 10 Dec 2020, 03:02

Serbian Huskies love chasing their tails...good morning Misha!