Starting Problem Fixed, but do I have a fuel pressure problem? - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Pauly2 · 01-14-2005, 23:51

Hey all

I had a starting problem where the starter would kick over for about 5 to 10 seconds before starting. I found that if I turned the key to on a few times before starting it would reduce the problem. Given that, I decided to plug in a fuel pressure gauge to find out what was going on.

Finally got around to plugging the gauge in today, and I found my problem. When I turned the car off after running it, I would lose all fuel pressure. So, with the fuel pump running, I went about clamping off the fuel line between the pump and the rail to see if the pump was maintaining back pressure. Found that it was. Meanwhile, the hose going from the clamp to the fuel rail had no pressure in it. So then I switched the pump back on and moved my clamp to the return line. The pressure on the gauge skyrocketed, I stopped the fuel pump, and decided that the regulator must be faulty. So I undid the clamp off the line, and hang on a second, the line is keeping pressure now! Started the car, stopped the car, line maintains pressure after being switched off. My starting problem is solved (or so far it seems to be!)

I think that the pressure put into the system by clamping the line freed something up, perhaps in the regulator. Any of you guys have any theories??

Second question. Now that I have the fuel pressure gauge installed I know what pressure I am running. My baby is an EL Fairmont Ghia, so the specs say that at idle I should be getting 250 kPa. In fact, I am only getting about 213 kPa

Car drives fine. Would there be any benefit in getting a new regulator so that I am running pressure back within specs?

Thanks everyone.

shano6 · 01-15-2005, 15:11

Yes it sounds like the reg is faulty. If the reg diaphragm/spring is sticking, by clamping the return line and increasing fuel pressure, this can temporarily free up the reg. Also replace your fuel filter if you haven't already done so. If you know someone with a spare old reg floating around, you could try this to make sure before buying a new one.

Pauly2 · 01-17-2005, 00:20

Thanks Shano. As it turns out you are right. The old starting problem came back (was only temporary as you said), and I have retested and am 99% sure it is the regulator. I'm getting a new one this week and will hopefully get a chance to install it this weekend. Should hopefully fix the overall low pressure problem too.

Seeya

shano6 · 01-18-2005, 02:34

You've probably been a bit unlucky, as I haven't had many Fords in general with regulator problems......Anyway, hopefully all's well again - compared to before it'll feel like you've just fitted a bigger cam! By the way, how many k's are up on the car?

Pauly2 · 01-21-2005, 19:37

Well - fitted a new regulator today. Starting problem gone. Still running at the same lower than spec pressure as before though - not sure why that would be

Did a fuel flow test and it is flowing a lot better than specs say it should, so I think I'll just leave it now.

By the way Shano, it has 136000 kms on the clock.

shano6 · 01-23-2005, 03:05

Maybe the actual gauge is not really accurate. If you can get hold of another gauge you could compare readings, but if it's running 100% I wouldn't be bothered.........

Pauly2 · 01-24-2005, 00:34

Thanks Shano. Was talking with a mate of mine yesterday and he said kind of the same thing - he said that the cheaper pressure gauges can be pretty inaccurate even from new.

Hearing this, and knowing that the new reg is holding exactly the same pressure on the gauge as the old one was at idle, I figure it is too much of a coincidence that both regulators would be out of spec exactly the same amount.

Tell you what - its damn good having the starting problem fixed

Thanks for your help.