Technical Doblo starting issues

[Jas121sim]

Hi all,

I'm new to this forum and fairly new to the world of fiat. I have a Fiat Doblo Diesel multijet 1.3 that refuses to start on me and I was wondering whether anyone was able to assist.

It initially cut out whilst sitting in traffic last Sunday and wouldn't start. During the day it was occasionally hesitating whilst accelerating. I recovered it home and have replaced the following parts:

Cam shaft sensor
Crank shaft sensor
(Starter motor replaced approximately 2 weeks before the car died).

I got the car to start from a tow start and drove it for around 5 miles with no problems or dead spots. I got it back home and it wouldn't start from stationary.

When we measured the voltage across the battery it was 12.5V however it dropped to around 8V whilst the engine was cranking. So we carried out the followImg tests:

We've carried out a voltage drop test on the starter and it lost less 0.2v on both the positive and negative sides while the engine was cranking.

We've disconnected the alternator and tried starting it.

We've also checked the glow plugs and measured 12.5 v across them and have tried jump starting the car and it refuses to start still.

We're now at a loss as to what could be preventing it from starting and we'd be grateful if anyone were able to shed some light Ono this? Apologies that it's a lengthy message I just wanted to get in everything we've tried.

I look forward to hearing from you soon.

All the best,

Jas121sim

 

[varesecrazy]

Hi,
the tow starting could be a clue..does it now refuse to fire when towstarted..??

the injection relies on HIGH pressured to work..if it cranks slowly- then you get reduced pressure - so tow starting can make the difference.

use SEARCH in "advanced" to search the Panda 1.3 posts - there is FAR MORE info over in that section,
Charlie

 

[Jas121sim]

Hi Charlie,

Thanks for your response. It starts from a tow start every time and it seems to be cranking fine.

When cranking the car feels like it's just about to fire.

I'll have another look in the punto forums to see if I can see a post with similar symptoms.

Thanks and all the best,

Jason

 

[varesecrazy]

Hi Charlie,

Thanks for your response. It starts from a tow start every time and it seems to be cranking fine.

When cranking the car feels like it's just about to fire.

I'll have another look in the punto forums to see if I can see a post with similar symptoms.

Thanks and all the best,

Jason

PANDA..,

you can use software to read the fuel rail pressure,
I suspect it's LOW when cranking on the starter.

as an aside,
there was a LONG thread where somebody's panda MJ ,
got tricky to start.. the diesel tank was full of gunk..aparently in can live / grow in Diesel.

just a thought - they did LOADS of diagnostics before dropping the tank.
https://www.fiatforum.com/panda/418078-1-3-diesel-refusing-start-4.html
so thread may give useful pointers.

 

[Tazzy7]

I had a similar problem caused by the heater relay box. Although it appeared to be working it was getting voltage in but not sending it out the other way.

Attaching a head light bulb to the mechanism to see if power was being received was how they tested it. After replacing the box and a couple of tweaks it starts fine.

My problem was the first start in the morning or when the car had been left for 6+ hours. After initially jump starting it the car would start fine all day until it was left.

Problem is now gone so if u still have the problem ask your local garage to test the heater relay box. Hope this helps

 

[varesecrazy]

Jas121sim

 

[Jas121sim]

Hi Varesecrazy and Tazzy7 Ill have a check of the heater box relay. I took it in to a garage and was told that it's low compression and that it's either the head gasket, the piston rings or a valve unseated. However, his "compression test" consisted of him putting his hand over the air intake and said it should be sucking his hand in and that there was no suction so I doubt his judgement.

I had a friend look at it and although he's not sure what the problem is he said he highly doubts it being an issue with either of the above.

I'm suspecting either an electrical fault or a fault with the EGR valve. When it does try to start there's a gulping noise coming from this area.

Is it possible that the EGR is stuck open and is stopping the engine from starting?

All the best,

Jason

 

[burrowsdeano]

If your anywhere near southampton I could take a look for you. Think I've seen just about everything that causes these to not start