2001 V70 Crank no Start

01_Nautic_V70 · Post by **01_Nautic_V70** » 08 Dec 2019, 21:37

Disconnect the MAF. Does the engine run in limp home mode?

Oka · Post by **Oka** » 08 Dec 2019, 22:45

01_Nautic_V70 wrote: ↑08 Dec 2019, 21:37 Disconnect the MAF. Does the engine run in limp home mode?

Just disconnected the battery and pulled down the CEM to check the fuel pump relay, so, I can't do that test now.

01_Nautic_V70 · Post by **01_Nautic_V70** » 09 Dec 2019, 06:07

For me, this was the clue. I knew I was getting spark, knew it was getting fuel, so it had to be air. That things changed when MAF was disconnected was the pointer on where to look.

DanelleNavarro · Post by **DanelleNavarro** » 16 Aug 2020, 19:24

I'm having crank no start issues also however if it is the fuel pump why does my car start with a jump. I tried listening for the fuel pump noise and I didn't hear anything my friend also get tried to hear the fuel pump noise and didn't hear anything another friend same thing nothing we put the battery jumper cables to it and it started right up we don't understand how that is possible if the fuel pump is broken

01_Nautic_V70 · Post by **01_Nautic_V70** » 16 Aug 2020, 20:13

Sounds like you are getting fuel, are you getting spark? Air?

DanelleNavarro · Post by **DanelleNavarro** » 17 Aug 2020, 02:49

Not sure about the spark will check in the morning and what do you mean by air?

01_Nautic_V70 · Post by **01_Nautic_V70** » 17 Aug 2020, 06:02

Air is regulated by the electronic throttle module based on what the ECM tells it to do. The ECM looks at the mass air flow sensor to figure out how much air is going in. If you unplug the MAF (located just downstream of the air filter box) the car should go into a limp home mode where it uses its best guess for how much air is going in instead of the measured amount. If so, the car would start though it may idle rough.

DanelleNavarro · Post by **DanelleNavarro** » 19 Aug 2020, 16:09

Ok...I'll give that a try I also have changed my coil harness wires, the oil filter, and change the oil. I unplugged the relay for the fuel pump and swapped it out for the fog light relay but that didn't do anything the car will still start on a jump though. That's where my confusion begins. Because if it's the fuel pump would it still start on a jump? Also there is good fuel pressure on the fuel rail. However I have a problem with my number 2 cylinder misfiring constantly. Would that have anything to do with my problem starting the car?

Post by **abscate** » 19 Aug 2020, 19:41

What’s the measured fuel pressure at the rail? You can’t do this visually

Post by **chrism** » 20 Aug 2020, 08:56

DanelleNavarro wrote: ↑16 Aug 2020, 19:24 we put the battery jumper cables to it and it started right up

Sounds to me like a case of not enough battery power, after cranking the starter, to adequately power the fuel and/or ignition system(s).
If you haven’t done it already, try cleaning the battery terminals. After you do that and reconnect the cables put a volt meter across the battery terminals and see how much the voltage drops when cranking the starter. Your problem might be as simple as dirty battery terminals or a weak battery.

2001 V70 Crank no Start

Re: 2001 V70 Crank no Start