Ryannew2scoob

Hi all. Basically I've got the same problem I had a few months back. I have a my98 UK turbo impreza. Today I went out, turned the key and realised I didn't hear the fuel pump prime. Sure enough the car just turns over but won't start. I had the problem 4 or 5 months ago whilst at asda and ended up getting the AA out. They came to the conclusion it was the fuel pump so I changed it the next day but it made no difference. I ended up trying the spare key and it fired straight up. Obviously it points to a faulty key but now it's happened again only a few months later. Does anyone have any idea what could be causing this to happen? Cheers Ryan

Yamarashi

If you still have the standard Sigma alarm unit fitted it could well be the Sigma circuit board failing and disabling the fuel pump.

Ryannew2scoob

Well I've just been out to it and this time it started fine. What could be wrong with it? Has anybody else had a similar problem?

Yamarashi

Does it have the Sigma alarm fitted?

If so then the Sigma circuit boards have common issues and especially the fuel pump immobiliser relay that is fitted to the alarm boards.

It is quite likely this is in its intermittent stage of working and failing before it finally fails.

If you dont have a Sigma fitted forget all the above but I would still check whichever brand immobiliser you have for any faults.

Ukautograss

Immobiliser is cutting the power to the pump .

GreasyMustardTiger

Had the same problem with my '98 turbo. Was getting 12v at the connection for the pump outside the tank so presumed pump failure. Replaced it, and had the same intermittent problem.

If you pull the pump from the top of the tank there will be another electrical connector, make sure it is making good contact. Mine was ever so slightly loose. (My memory is hazy as to what the contact looked like but you should spot it). Nipped up the contacts and it's been absolutely fine ever since.
Apologies if I haven't described this very well!