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Finding it difficult to start the engine.

I have checked the following

ECU = changed
Fuel injectors = checked & cleaned
Fuel filter = changed
PCV = changed
Purge solenoid valve = checked it opens & closes
Coil resistance = checked
Spark plugs = changed
Spark plug leads = changed
Cam position sensor = changed for new one
Mass air flow sensor = checked
Throttle position sensor = checked
Injector relay = checked
Idle air control valve = checked resistance
Timing = checked
Fuel pressure regulator = Not checked
Oxygen sensor = Not checked
Clutch switch = Not checked

Not sure what else I can check!!

Any other ideas PLEASE

Fuel pump

Run some jumper leads across from a car with a known good battery.

gslender wrote:Fuel pump

Fuel pump has been tested but don't know if pressure is as per specications.

manga_blue wrote:Run some jumper leads across from a car with a known good battery.

I used a battery which started my other MX

The following 'blackwire' in-fuel tank wiring connection issue began as increasingly hard to start until it would no longer start: viewtopic.php?f=55&t=46425

93_Clubman wrote:The following 'blackwire' in-fuel tank wiring connection issue began as increasingly hard to start until it would no longer start: viewtopic.php?f=55&t=46425

Fuel pump is working using the GRN/F/P jumper wire test and is getting to the injectors because it does fire up eventually. It takes maybe 5 to 10 tries with the ignition key before the car starts.

There is a fairly common issue with either failing fuel pump or wiring to it in NBs where it can have this symptom - it runs fine, but hard to start... eventually it won't start and the pump and/or wires within the tank to the pump fail. If the pump isn't providing enough initial fuel pressure then the injectors will not be injecting the correct fuel at start and it will be difficult to start until pressure builds up.

Try this - turn ignition on/off with a 5 sec wait between on and off. Do that about 5 times and then try to start. If it starts correctly then it is very likely the fuel pump. If not, then move on and check the fuel pump off as being ok.

G

myredmx5 wrote:Fuel pump is working using the GRN/F/P jumper wire test and is getting to the injectors because it does fire up eventually. It takes maybe 5 to 10 tries with the ignition key before the car starts.

The fuel pump in the above example was fine & is still going strong. The problem was with the electrical connector block at the top of the tank (ie at the top of the removable guage/pump assembly), but only visible on the inside.

Initially identified it by testing the top two connectors with a multimeter for continuity from outside the tank - some resistance found, hence the impact on normal starting.

myredmx5 wrote:

manga_blue wrote:Run some jumper leads across from a car with a known good battery.

I used a battery which started my other MX

The coilpacks in an NA8 draw a fair bit of power. I've often had issues in my NA8 when the battery is getting a bit weak that there's enough power there to turn the motor OK but not really enough for the coilpacks to fire well. You really need to test with a bigger or boosted battery.

Have you tried taking a plug out and turning the motor to make sure you've got a solid spark? Ignition problems are much more common than fuel ones with NA8s.

Thanks for your help guys.

It seems to be the fuel pump with a dodgy terminal.

All good now, starts first time.