Long cranking on start issue on v6

minimutly · 29th November 2018, 21:35

As the title says, my 190 sometimes cranks for - oh, I don't know, 7 to 10 seconds before s l o w l y catching and coming up to idle speed. Only does it when cold. It's happened gradually, first noticed it last year, I thought it might have been an lpg solenoid leaking, but now I'm not so sure.
I've started giving it some throttle in case it might be the idle motor, the jurie's still out on that. Other than the starting issue it runs fine on petrol and lpg, no loss of power, missfiring etc.
Any one seen this?

Comfortably Numb · 29th November 2018, 21:54

Possibly the temperature sender. This tells the ECM if the engine needs choke (extra fuel to start and for cold running). If it isn't sending a signal, the ECM thinks the engine is warm (default), so supplies a lean mixture, - engine very difficult to start from cold. I had this on a Polo - got worse as the weather got colder. VW indie did diagnostic check twice, each time said it was throttle body, which I changed, and no better. Ran it past my Honda- trained spares guy - he handed me a sender and said "Try that". 5minute job on Polo - started perfectly ever after £13.00 incl Vat. Much better than burning out your starter, and killing your battery.

T-Cut · 30th November 2018, 09:50

The primary clue to loss of the temperature sensor signal at ignition on is the immediate operation of the radiator fan at high speed. If your poor starting is accompanied by a roaring fan, you have the answer.

Just for peace of mind, does the fuel filter have the orange clip installed?

TC

minimutly · 1st December 2018, 16:59

Hmmm, thanks both. I had wondered about the temp sender, and I can check that easily enough. I will also do a check to see if the fan runs on startup (I haven't heard it, but then I might not).
No orange clip fitted, i did check the filtr some years ago and it hadn't moved. I can't see being filter seperation since it runs well on petrol and lpg

T-Cut · 1st December 2018, 17:29

Quote:

Originally Posted by minimutly

No orange clip fitted. I did check the filter some years ago and it hadn't moved.

If the engine starting gets worse over time, I think you should revisit that. Fuel Filter Syndrome can be quite insidious in the beginning and not at all obvious. Hope you figure out the problem.

TC

minimutly · 24th March 2019, 22:12

Thread revival here - gave up looking for such an intermittent problem. However, ithas been getting worse, now even does it warm - say after sitting 20 mins.
So I put a pressure gauge on the schrader valve today - switched on, 45 psi. Cranked it, the pressure dropped by 5psi or so as it cranked, then it fired. Back up to 45psi. I couldn't make it give me the slow starting issues, so fingers crossed it doesn't fail me sometime soon.
It really does feel like poor fuel pressure though, or even, maybe like it ha s retarded timing, since when it does fire up it just slowly gains rpm, rather than bursting into life...

vitesse · 25th March 2019, 04:22

Similar to my daughter's car - solution to her's is here: https://the75andztclub.co.uk/forum/s...=286990&page=3

Regards

minimutly · 25th March 2019, 20:31

Quote:

Originally Posted by vitesse

Similar to my daughter's car - solution to her's is here: https://the75andztclub.co.uk/forum/s...=286990&page=3

Regards

Well yes the symptoms might be there, but as I said I measured the fuel pressure and it's fine - well, it was fine yesterday, and yesterday it wasn't doing the cranking forever thing.
Jury is still out until something definite comes to light.

minimutly · 1st September 2019, 09:09

Slow starting got worse and worse, getting to the point it allways happened.
I noticed it didn't do it when out of lpg- massive clue here?
Anyway, some info - lpg fitted 120k miles ago, BRC professional kit, good quallity stuff. Also, now and again had a stumble on gas, which never used to happen.
So my diagnosis - leaking gas injector, filling the inlet manifold with lpg, petrol and lpg way too rich, no start.
So yesterday I fitted a new set of injectors - £350 quid..
We'll see.

minimutly · 10th December 2019, 17:39

A set of injectors and starter motor later aaannnd,
Booga, still the same. However, a quick question posted on the lpg forum got me an answer I wasn't seeing - failed vaporiser diaphragm.
So I changed the diaphragm and bobs my uncle.
Welcome back sweet MG.

29th November 2018, 21:35	#1
minimutly Posted a thing or two mg zt Join Date: Mar 2014 Location: cardigan Posts: 1,087 Thanks: 28 Thanked 187 Times in 158 Posts	Long cranking on start issue on v6 As the title says, my 190 sometimes cranks for - oh, I don't know, 7 to 10 seconds before s l o w l y catching and coming up to idle speed. Only does it when cold. It's happened gradually, first noticed it last year, I thought it might have been an lpg solenoid leaking, but now I'm not so sure. I've started giving it some throttle in case it might be the idle motor, the jurie's still out on that. Other than the starting issue it runs fine on petrol and lpg, no loss of power, missfiring etc. Any one seen this?

29th November 2018, 21:54	#2
Comfortably Numb Posted a thing or two Rover 75 Saloon Join Date: Dec 2017 Location: Penrith Posts: 1,336 Thanks: 165 Thanked 303 Times in 241 Posts	Possibly the temperature sender. This tells the ECM if the engine needs choke (extra fuel to start and for cold running). If it isn't sending a signal, the ECM thinks the engine is warm (default), so supplies a lean mixture, - engine very difficult to start from cold. I had this on a Polo - got worse as the weather got colder. VW indie did diagnostic check twice, each time said it was throttle body, which I changed, and no better. Ran it past my Honda- trained spares guy - he handed me a sender and said "Try that". 5minute job on Polo - started perfectly ever after £13.00 incl Vat. Much better than burning out your starter, and killing your battery.

30th November 2018, 09:50	#3
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	The primary clue to loss of the temperature sensor signal at ignition on is the immediate operation of the radiator fan at high speed. If your poor starting is accompanied by a roaring fan, you have the answer. Just for peace of mind, does the fuel filter have the orange clip installed? TC

1st December 2018, 16:59	#4
minimutly Posted a thing or two mg zt Join Date: Mar 2014 Location: cardigan Posts: 1,087 Thanks: 28 Thanked 187 Times in 158 Posts	Hmmm, thanks both. I had wondered about the temp sender, and I can check that easily enough. I will also do a check to see if the fan runs on startup (I haven't heard it, but then I might not). No orange clip fitted, i did check the filtr some years ago and it hadn't moved. I can't see being filter seperation since it runs well on petrol and lpg

24th March 2019, 22:12	#6
minimutly Posted a thing or two mg zt Join Date: Mar 2014 Location: cardigan Posts: 1,087 Thanks: 28 Thanked 187 Times in 158 Posts	Thread revival here - gave up looking for such an intermittent problem. However, ithas been getting worse, now even does it warm - say after sitting 20 mins. So I put a pressure gauge on the schrader valve today - switched on, 45 psi. Cranked it, the pressure dropped by 5psi or so as it cranked, then it fired. Back up to 45psi. I couldn't make it give me the slow starting issues, so fingers crossed it doesn't fail me sometime soon. It really does feel like poor fuel pressure though, or even, maybe like it ha s retarded timing, since when it does fire up it just slowly gains rpm, rather than bursting into life...

25th March 2019, 04:22	#7
vitesse I really should get out more....... Rover 75 Saloon Join Date: Jul 2011 Location: Gävle Posts: 2,534 Thanks: 395 Thanked 823 Times in 652 Posts	Similar to my daughter's car - solution to her's is here: https://the75andztclub.co.uk/forum/s...=286990&page=3 Regards

1st September 2019, 09:09	#9
minimutly Posted a thing or two mg zt Join Date: Mar 2014 Location: cardigan Posts: 1,087 Thanks: 28 Thanked 187 Times in 158 Posts	Slow starting got worse and worse, getting to the point it allways happened. I noticed it didn't do it when out of lpg- massive clue here? Anyway, some info - lpg fitted 120k miles ago, BRC professional kit, good quallity stuff. Also, now and again had a stumble on gas, which never used to happen. So my diagnosis - leaking gas injector, filling the inlet manifold with lpg, petrol and lpg way too rich, no start. So yesterday I fitted a new set of injectors - £350 quid.. We'll see.

10th December 2019, 17:39	#10
minimutly Posted a thing or two mg zt Join Date: Mar 2014 Location: cardigan Posts: 1,087 Thanks: 28 Thanked 187 Times in 158 Posts	A set of injectors and starter motor later aaannnd, Booga, still the same. However, a quick question posted on the lpg forum got me an answer I wasn't seeing - failed vaporiser diaphragm. So I changed the diaphragm and bobs my uncle. Welcome back sweet MG.