thanks

i recently replaced the head gasket on my mgf tf. now it starts and runs for about 2 seconds then stops.. the run period remains constant. can anybody provide any information as to where i should start looking...thanks
 

The engine dying in the arse may not have anything to do with the resent head gasket replacement, you need to determine if you are getting fuel when it cuts out, you also need to determine if you re getting spark when it dies and another possibility is a blocked exhaust.

Welcome to the forum. As Cobber has said it probably doesnt relate directly to the head gasket change. More likely to be a loose connection or something such as the immobiliser even.

Can you give us a bit more to go on. F or TF, what year, what you have already checked ?

Have a look at the fuel pump, as I’ve said before, I have never had a problem with mine although I’ve looked at a fair number of posts to have gain an understanding of the range of problems with their failures.
If left dormant for a time they can find waking up problematic & as the pump relies on fuel passing through to keep it lubricated, being off the road for a while won’t help.
If it runs for a few seconds, that infers an ignition system wanting to get on with the job, however once the initial squirt of fuel is gone & the fuel rail pressure drops & it turns into a Norwegian Blue.
Try again & the pump might have enough puff to build pressure for another go.
Others might have further suggestions.
M

Starting and running for 2 seconds looks like alarm ecu is not speaking with engine ecu.
What system do you have Lucas or Pektron?
As asked previously - do you have F or TF and what yearmof production?
Is your fob square with 2 buttons or oval one?
Can you lock and unlock your car with the remote/fob without a problem?

thank you all for you replies.. i have a 2002 TF. I have replaced the fuel pump and the fuel pressure regulator. I have checked the spark, still sparks, i have checked the fuel pressure 3bar. after starting i spayed some aerostart in to the air inlet. the motor revved well. the locking and alarm work but i am not sure if correctly. is there anywhere i can read on how this system works? the alarm fob has a rounded base

So it starts Ok but when you go to drive it, the damned thing stumbles, burps, farts and dies in the arse yeah?
Sounds like ignition problems, check coils, plugs, HT leads etc. What is the feed voltage to the coils? Check ignition timing and O2 sensor.
If all that is well check to see the cat converter isn't partially blocked.

Whilst It's ell known how much I despise alarm systems, it pains me to admit that I doubt the alarm is your problem, it wouldn't start at all if that was giving you grief.

yeah, thanks.. it only runs for about a second then stops.. there is still spark, and the fuel pressure remains constant.

There maybe spark but it mignt not be strong enough under load.
And the cat convertor may let gas past in small quantities like at Idle but when you go toput larger volumes of gas through it just cant let it pass due to being partially blocked

thanks to all that replied to my post on engine starting but not continuing to run..after a lot of testing I decided to pull out the injectors and test the continuity of the electrics there. when cleaning the contacts I noticed a bent pin . It was pin C from the MAP sensor. I put it back together and now it continues to run.. unbelievable!!

Although I didn't contribute thank you for letting us know the problem was solved and how.
I'm fairly new to MG ownership and read every post trying to get to know them and so it's nice to see a problem come to a happy conclusion!

Connected the solution to the problem...