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Checking fuel pressure
pekwah1 - 6/5/25 at 06:08 AM

Hi guys,

Having recently taken delivery of my striker, I just have one main issue to fix.
On higher RPM the car stutters and feels like a fuelling issue.
Engine is a 2.0 blacktop zetec on standard ECU.

I have a low pressure pump gravity feed from the tank, which feeds a swirl pot, and then goes to a high pressure pump, which then feeds into the factory fuel rail.

How would you go about testing the fuel?
My current thoughts:

1. Take the hose off from the HP pump and time it into a container to get the flow rate
2. Buy a fuel pressure gauge and connect that in after the HP pump

Thanks
Andy

JAG - 6/5/25 at 06:58 AM

I don't think you need to measure fuel pressure - and it will be very diffcult and expensive to measure fuel pressure at maximum RPM with the engine under load.

You'd need to have a pressure sensor that can log readings while the car is being used OR you would need to put the car on a rolling road. Both do-able but costly.

I'd start by calculating the fuel flow rate needed by your engine at maximum RPM.

Then I'd measure the fuel flow rate of the set up you have. Both high and low pressure pumps need to flow enough fuel. The method you mention should be OK.

If the flow rate of the high and low pressure pumps is less than your engine needs at maximum RPM then you'll have a fuel pressure issue.

JAG - 6/5/25 at 09:58 AM

There are on-line calculators to tell you how much fuel your engine will consume....

Raceworks.com.au

OR

deatschwerks.com

pekwah1 - 6/5/25 at 10:01 AM

Thanks Justin,

I’ll see what kind of flow I’m getting, I have got a fuel pressure tester to use as well, I know I can’t really use it under loads but might give me some idea…

coyoteboy - 6/5/25 at 11:53 AM

Not got a wideband on it?

pekwah1 - 6/5/25 at 05:41 PM

No wideband….

Think I’ve found the issue(s) though… mixture of blocked filters and badly placed pumps / fuel hoses…
Systematically going through and sorting and hopefully as simple as that

bi22le - 12/5/25 at 07:53 PM

quote:
Originally posted by pekwah1
No wideband….

Think I’ve found the issue(s) though… mixture of blocked filters and badly placed pumps / fuel hoses…
Systematically going through and sorting and hopefully as simple as that


Standard 2nd hand kit car job. I had to do the same. Good practice to change the fuel filter, its often forgotten. I was well chuffed when I dug out my filter and HP pump to find out they were both decent Sytec ones. Meant I didnt have to fork out for new ones.

Glad to hear you are back on the scene with a striker. Fancy a track day!!?

pekwah1 - 12/5/25 at 08:37 PM

Actually no I was wrong, still got the problem.
So far have changed sparks, leads and coil.
Flushed all fuel lines, tested HP pressure, cleaned injectors.
Removed intake manifold and remounted with new gasket.

Still sounds like it’s firing on 3 cyls when under load, I have no idea what the problem is.

ECU doesn’t give any error codes

coyoteboy - 13/5/25 at 01:27 PM

Checked the TPS output (at the ECU input pins)?

pekwah1 - 13/5/25 at 04:13 PM

I haven’t but will check that out thanks

pekwah1 - 15/5/25 at 04:08 PM

Well I’ve checked out the TPS.
Turns out I did have a broken wire.
Have re-crimped and sorted but didn’t make any difference.

Then checked the wiring and decided I had the positive/earth the wrong way round so switched these and still made no difference.

I’ve got earth on A
Signal on B
5v on C

With throttle closed signal is just under 1v, on WOT it’s just under 5v so feels like TPS is ok.
Also have continuity at the ECU.

So I’m thinking it’s nothing to do with the TPS, any thoughts welcomed