T5 refusing to start :(

[Al115]

Have I missed something here, why are we talking about injectors and fuel pump relays when the chap has fuel but no spark?

[Al115]

AFAIK (limited) you could also check the crank sensor as a dodgy one might prevent the ECU from sending signals to spark. Another cause that I have had in the past albeit on a different Volvo engine. At least sensors are easy enough to check out with a multimeter or swap for known good one... would be an easy / cheap fix.

[850t5]

Is there a spark to the distributor cap?

I have no idea but I would think not as from the ignition coil to the plugs have been replaced. Surely if the spark made it to the dizzy cap it would make it to the plugs as its all new??...

The injector relay can stop the spark?

[850t5]

AFAIK (limited) you could also check the crank sensor as a dodgy one might prevent the ECU from sending signals to spark. Another cause that I have had in the past albeit on a different Volvo engine. At least sensors are easy enough to check out with a multimeter or swap for known good one... would be an easy / cheap fix.

Someone said it could be the crank sensor Would the cam sensor cut the spark if it was faulty?

I'll play with both and see what happens Thanks

[96T5Andy]

I. Had same fault sand no bananas answer correct. Check relay. Kills spark ass well as injector.

[96T5Andy]

Al you can have fuel at rail without injectors Firing can You not?

[nobananas]

To rule out that relay completely, disconnect it then bridge together the two fattest wires or read the diagram off the side of the relay and bridge the two wires that correspond to the pin numbers linked to the switch symbol.

[Al115]

Al you can have fuel at rail without injectors Firing can You not?

Certainly. Noid light would confirm the injectors or not... I have a set but I'm a long way away to lend them!

[850t5]

I've ordered a cam and crank sensor and until they arrive I'll check the rest of it over I fitted a MBC about 2 weeks before it died.. could that have knackered my injectors? I'm off to check the relay above the rad

Thanks to everyone so far.. you've helped no end

[Al115]

Mate if you PM me I will loan you my set of noid lights for you to test your injector pulse with. That way you will know if fuel is getting to the engine (it's highly unlikely that 5 injectors have failed, more likely that they are not getting a pulse, IF you are lacking fuel).

Or can't you just crank the engine and then whip a plug out and see if it smells fuelly in there?

[Flatout Phil]

I have been looking at the Feb 2010 issue of Volvo Driver (VOC) p37 and the 850 registrar describes a very similar problem at great length. The solution was 'the electrical portion of the ignition switch'. Jod Spiro describes what sounds like exactly the same process of trying this and that, but this solved it for him. Interestingly, he had swapped out the switch because the old one was worn causing the ABS light to come on because the internal ball-bearing had failed.

Worth a try.

[850t5]

Mate if you PM me I will loan you my set of noid lights for you to test your injector pulse with. That way you will know if fuel is getting to the engine (it's highly unlikely that 5 injectors have failed, more likely that they are not getting a pulse, IF you are lacking fuel).

Or can't you just crank the engine and then whip a plug out and see if it smells fuelly in there?

Thanks for the kind offer I'll eliminate the other avenues first but might call on your generous offer if it doesn't work out

Cheers

[AndysR]

I have no idea but I would think not as from the ignition coil to the plugs have been replaced. Surely if the spark made it to the dizzy cap it would make it to the plugs as its all new??...

The injector relay can stop the spark?

I was thinking more along the line that if the spark has reached the dissy then maybe the carbon centre ignition coil button could have broken and may not be putting the spark across to the rotor arm. Do you have a spark to the cap when cranking? If you not sure, remove the coil lead from the cap place a screw driver inside the coil and rest it close to a suitable earthing point then look for a spark whilst someone else is cranking the engine just be careful not to get a shock while your checking.

I was under the impression that the injector relay was the switch that activated the injectors and the coil pack once you start cranking provided it gets a signal to tell it the engine is turning over/running. Which is why I was going in the direction I was with the fuel at injector query rather than rail...

[850t5]

I have been looking at the Feb 2010 issue of Volvo Driver (VOC) p37 and the 850 registrar describes a very similar problem at great length. The solution was 'the electrical portion of the ignition switch'. Jod Spiro describes what sounds like exactly the same process of trying this and that, but this solved it for him. Interestingly, he had swapped out the switch because the old one was worn causing the ABS light to come on because the internal ball-bearing had failed.

Worth a try.

Thanks mate I'll give that a try too.

By the time I'm finished ill have a new t5

[Flatout Phil]

Just came across this thread in the HOW TO section:
http://www.vpcuk.org/forums/showthread.php?t=15085
You never know...

[850t5]

Just came across this thread in the HOW TO section:
http://www.vpcuk.org/forums/showthread.php?t=15085
You never know...

Thanks That's very handy to have

It says about the flywheel sensor? Is that the crank sensor or is it one I've not heard of yet?

I'm still learning about these cars but they are friendly to work with so far

[MoleT-5R]

There's also a relay tucked under the radiator top panel on the right, the wiring often rots as it goes into the connector, this kills the feed to the cam sensor (well it did on mine !) and kills the spark.

Interestingly did anyone know that you can't start an 850 with the cam sensor unplugged but it will continue to run if you unplug it whilst it's running ? (okay not that interesting !)

As mentioned here this relay is the main relay and as they say it will stop you getting a spark, I have had this problem myself and discovered that one of the two thin wires going to the relay, had corroded through and broke off, fixed it and it fired up straight away, then whilst tidying the wiring up i moved the other thin wire and the car died again. Thus this was then fixed and shes going beautifully, pitty it only took me a year a half to solve this!!!!!!

[Al115]

It says about the flywheel sensor? Is that the crank sensor or is it one I've not heard of yet?

Yes it is the crank sensor.

[nottsgreent5]

i had a faulty starter kill the spark on a mates t5 prob sounds a bit strange but changed the starter and all was fine again think it must of been pulling to many amps could be worth a try

[850t5]

Cracked it

I took the crank sensor off to find this...



I put a new one in and it fired up straight away Idk if it's because the car has been standing for a few months but the engine was ticking really loud :/ Like tappets but louder...

I'll give her a proper service and check it all over Fingers crossed

Thanks for all for the pointers, it's been a very educational journey lol