Can anyone help? ‘04 facelift MG ZT T 2.5l KV6 Non Start. - Page 8

SD1too · 8th February 2021, 19:22

Quote:

Originally Posted by Timefortea23

TOAF seems to report there are problems with coil packs 1,2,3 & 4 yet they are sparking.

What makes you believe they're sparking?

Simon

Timefortea23 · 8th February 2021, 19:34

Quote:

Originally Posted by SD1too

What makes you believe they're sparking?

Simon

We tested a couple by removing the spark plug, plugging it into the coil pack and resting the threads of the plug against the block to earth it. Then cranked it and we got good spark.

SD1too · 8th February 2021, 20:05

Quote:

Originally Posted by Timefortea23

We tested a couple by removing the spark plug, plugging it into the coil pack and resting the threads of the plug against the block to earth it. Then cranked it and we got good spark.

Excellent.

OK, so you've got a spark and your fuel pump is now running but the engine doesn't fire.

Do you have the "orange" clip fitted to your fuel filter?

Simon

Timefortea23 · 8th February 2021, 20:11

Quote:

Originally Posted by SD1too

Do you have the "orange" clip fitted to your fuel filter?

Yep. We took the fuel filter housing apart and fitted a new fuel filter in at the start of the current issues back in early Jan. It had the orange clip and had not separated. We re fitted the clip after the new filter was installed.

Also we've unhooked the fuel pipe in the engine bay to check and we're now getting a good amount of fuel being pumped up.

SD1too · 9th February 2021, 07:33

First of all Dan I would set the sparking plug gaps to the specified 1.0 mm (currently 0.8 mm).

If there's still no joy then I can think of three possibilities:

Camshaft sensor.
Low fuel pressure.
Further undetected wiring damage.

I think the camshaft sensor is unlikely. The engine originally stopped when running which would not result from this sensor failing. It would also be a remarkable coincidence for two different faults to occur at exactly the same time.

Although you've proved that fuel is being delivered to the injectors, it must be at the correct pressure. You've dismantled the filter which isn't recommended by those that have done it. It's apparently very easy to distort the seal during reassembly and any defect here will affect fuel pressure. This is what I would be checking next. You've probably noticed the Schrader valve with the blue cap nestling at the end of the fuel rail. You should see 3.5 bar (54 psi) of pressure here, any less and you've found the problem.

I hope you have success soon. You deserve it.

Simon

P.happy.T · 3rd April 2021, 14:05

Hi I’m Dan’s Dad & am giving him some help in trying to sort out the troublesome ZT-T V6 190.
Since the last post we have achieved an engine start & run but not satisfactory.

To re-cap we've done the following:-
New Engine Fusebox but we replaced the original as it didn't make a difference.
Repair power lead to fuel pump, the cause of original failure.
Taken faulty inertia switch out of circuit
Fuel Pump & Filter inspected pressure tested at injector rail as 53 psi
Tried running with replacement ECU & Immobiliser set, no change so went back to the originals
T4 diagnosis (This was not able to read the engine speed, so a new crank sensor was recommended)
New Crank Sensor
New TMAP
New Coolant Temp sensor
Tested Cam sensor by substitution from 1.8 K-Series
New Thermostat housing & pipes in the engine’s Vee (not the cause of the fault, but it was leaking and needed replacement & at that point we were still optimistic !!!)

Now the engine will start, but when cold it needs Easy Start squirted into the throttle butterfly. Having driven it approx 15 miles The Engine Fault Light flashes continuously & the car is giving perhaps 40 hp so behaving as in some form of limp mode.
There seems to be very little vacuum in the inlet manifold could the VIS / Plenum arrangement be at fault or could a cam belt have jumped & tooth or more ?

Any suggestions on what to do next please ?
(Don’t want it to go spares or repairs after spending all this time & effort on a reasonable looking car).
Thanks Paul

SD1too · 3rd April 2021, 14:23

Quote:

Originally Posted by P.happy.T

Tested Cam sensor by substitution from 1.8 K-Series

Hello Paul,

Are you running the V6 with a 1.8 K series camshaft position sensor fitted?

Quote:

Originally Posted by P.happy.T

There seems to be very little vacuum in the inlet manifold ...

Have you checked the T connector in the cylinder head breather tubes? The tubes are known to break where they join the connector.

I've also sent you a Private Message Paul.

Simon

P.happy.T · 3rd April 2021, 21:35

Hi Simon,
We had no luck with the 1.8 K Series as its male plug wasn't compatible with the V6's female socket. The original KV6 cam sensor seems to work without Easy Start from a warm engine by using patience & plenty of starte rmotor supported by a new battery.

I'll, take a look at the breathers tomorrow but having recently flushed them through with petrol to get rid of excess oil I didn't notice any faults in the breather pipes & their junctions.
Thanks,
Paul

SD1too · 4th April 2021, 07:58

Quote:

Originally Posted by P.happy.T

The original KV6 cam sensor seems to work without Easy Start from a warm engine by using patience & plenty of starter motor supported by a new battery.

Hi Paul,

You shouldn't need plenty of starter motor and patience though should you.

I'm curious to know why you've renewed the crankshaft, TMAP and coolant temperature sensors but stopped short of the camshaft position sensor which will definitely prevent the engine starting if faulty.

Simon

P.happy.T · 4th April 2021, 16:46

Hi Simon,
We replaced the crank sensor because we had a T4 man bring his diagnostics to the stricken car, he said he couldn't 'get a signal from the crank.
We replaced the TMAP as another person had "Haynes Professional' software that suggested we would get 4 K ohms on one pair of terminals & 1 ohm on the other pair, we couldn't read that on the original so tried a new one with no success & very similar resistance readings to the original.
We replaced the coolant temperature sensor as the company that sold us the coolant pipes recommended this be changed at the same time.

We have not changed the cam sensor yet as the car does just about start but is virtually undriveable. Also The T4 guy said he could read it.

From the symptoms I've described do you think we should fit a new cam sensor ? Would that cause the poor starting & "limp mode" type performance ?

I don't have my own code reader & haven't been impressed with the information I have received from them to date anyway .

We are pretty dispondent with the ZT-T situation given that we repaired the broken pump feed wire months ago !

9th February 2021, 07:33	#75
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,345 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	First of all Dan I would set the sparking plug gaps to the specified 1.0 mm (currently 0.8 mm). If there's still no joy then I can think of three possibilities: Camshaft sensor. Low fuel pressure. Further undetected wiring damage. I think the camshaft sensor is unlikely. The engine originally stopped when running which would not result from this sensor failing. It would also be a remarkable coincidence for two different faults to occur at exactly the same time. Although you've proved that fuel is being delivered to the injectors, it must be at the correct pressure. You've dismantled the filter which isn't recommended by those that have done it. It's apparently very easy to distort the seal during reassembly and any defect here will affect fuel pressure. This is what I would be checking next. You've probably noticed the Schrader valve with the blue cap nestling at the end of the fuel rail. You should see 3.5 bar (54 psi) of pressure here, any less and you've found the problem. I hope you have success soon. You deserve it. Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

3rd April 2021, 14:05	#76
P.happy.T Newbie MG ZT-T Join Date: Jan 2021 Location: Leicester Posts: 25 Thanks: 0 Thanked 6 Times in 1 Post	Hi I’m Dan’s Dad & am giving him some help in trying to sort out the troublesome ZT-T V6 190. Since the last post we have achieved an engine start & run but not satisfactory. To re-cap we've done the following:- New Engine Fusebox but we replaced the original as it didn't make a difference. Repair power lead to fuel pump, the cause of original failure. Taken faulty inertia switch out of circuit Fuel Pump & Filter inspected pressure tested at injector rail as 53 psi Tried running with replacement ECU & Immobiliser set, no change so went back to the originals T4 diagnosis (This was not able to read the engine speed, so a new crank sensor was recommended) New Crank Sensor New TMAP New Coolant Temp sensor Tested Cam sensor by substitution from 1.8 K-Series New Thermostat housing & pipes in the engine’s Vee (not the cause of the fault, but it was leaking and needed replacement & at that point we were still optimistic !!!) Now the engine will start, but when cold it needs Easy Start squirted into the throttle butterfly. Having driven it approx 15 miles The Engine Fault Light flashes continuously & the car is giving perhaps 40 hp so behaving as in some form of limp mode. There seems to be very little vacuum in the inlet manifold could the VIS / Plenum arrangement be at fault or could a cam belt have jumped & tooth or more ? Any suggestions on what to do next please ? (Don’t want it to go spares or repairs after spending all this time & effort on a reasonable looking car). Thanks Paul

3rd April 2021, 21:35	#78
P.happy.T Newbie MG ZT-T Join Date: Jan 2021 Location: Leicester Posts: 25 Thanks: 0 Thanked 6 Times in 1 Post	Hi Simon, We had no luck with the 1.8 K Series as its male plug wasn't compatible with the V6's female socket. The original KV6 cam sensor seems to work without Easy Start from a warm engine by using patience & plenty of starte rmotor supported by a new battery. I'll, take a look at the breathers tomorrow but having recently flushed them through with petrol to get rid of excess oil I didn't notice any faults in the breather pipes & their junctions. Thanks, Paul

4th April 2021, 16:46	#80
P.happy.T Newbie MG ZT-T Join Date: Jan 2021 Location: Leicester Posts: 25 Thanks: 0 Thanked 6 Times in 1 Post	Hi Simon, We replaced the crank sensor because we had a T4 man bring his diagnostics to the stricken car, he said he couldn't 'get a signal from the crank. We replaced the TMAP as another person had "Haynes Professional' software that suggested we would get 4 K ohms on one pair of terminals & 1 ohm on the other pair, we couldn't read that on the original so tried a new one with no success & very similar resistance readings to the original. We replaced the coolant temperature sensor as the company that sold us the coolant pipes recommended this be changed at the same time. We have not changed the cam sensor yet as the car does just about start but is virtually undriveable. Also The T4 guy said he could read it. From the symptoms I've described do you think we should fit a new cam sensor ? Would that cause the poor starting & "limp mode" type performance ? I don't have my own code reader & haven't been impressed with the information I have received from them to date anyway . We are pretty dispondent with the ZT-T situation given that we repaired the broken pump feed wire months ago !