2.9L & 3.0L V6 Tech General discussion of 2.9L and 3.0L V6 Ford Ranger engines.

Sluggish starting, zero fuel pressure, but it does start

Old 08-09-2018
Thread Starter
Join Date: Mar 2016
Location: Spicewood
Posts: 31
Sluggish starting, zero fuel pressure, but it does start

2003 Mazda B3000
3.0 L V6
289,000 miles

About a week ago it started taking longer to start. It would start, but would have to turn over eight or ten times. It takes longer for it to start cold than warm. Once it starts, it seems to run pretty much like normal. I have good acceleration when I need it. As good as this engine offers. :)

I had the battery tested and it showed good. I went to test the fuel pressure. I rented two different fuel pressure test kits and both showed pure zero pressure. Not just low pressure, but zero. Is that even possible, if it will start? I pressed my knife tip into the Schrader valve and some fuel came out. And on the second test, some fuel leaked while putting the Schrader adapter on, so it should have had fuel to register the pressure on. How is it registering at zero?

Assuming the zero reading is accurate, what is the most likely cause?

The gas pedal also seems to feel different. Kind of sluggish or spongy, but that may just be in my head since I'm paying more attention every time I start it.

Thanks for any input and advice.

Edit: I replaced the fuel filter less than a year ago.

Last edited by jrandallc; 08-09-2018 at 06:04 PM.
Old 08-09-2018
wydopnthrtl's Avatar
iTrader: (2)
Join Date: Dec 2005
Location: Ohio
Posts: 2,486
You need to get an accurate fuel pressure measurement.

If it were 0psi it wouldn't run.

With that many miles I'd start by changing the fuel filter.
Old 08-10-2018
RF Veteran
iTrader: (1)
Join Date: Jan 2014
Location: Vancouver, BC
Posts: 12,752
Test the pressure gauge on a tire, they use the same type of valve, a schrader valve

You are correct 0 psi would be a no start, but some pressure gauges won't show pressure under 5psi or even 10psi

1998 and up Rangers use 50-60psi fuel pressure, tire holds 30psi, so fuel should squirt out quite a few feet if you press on schrader valve's pin, be careful when doing that
And the system should HOLD fuel pressure for MONTHS, so even after a few weeks of being off you should still see 30+ fuel pressure

It reads like fuel pump is the issue, can you hear it run when you turn on the key?
It only runs for 2 seconds, but it does this EACH TIME you turn key from off to on, so repeat this on and off until you confirm pump is running each time
Fuel Pump Relay in engine fuse box can start to fail, so doesn't close each time key is turned on, rare failure but not non-existent failure

There are a few failure modes for fuel pumps
Motor simply quits working, so 0 psi and no sound when key is turned on
Broken lift line in the tank, fuel squirts out the broken line back into the tank so no fuel is lost but it lowers pressure at the engine, the larger the break the lower the pressure
Pump failure, motor turns, but the pump section can't pump much fuel, impeller issue usually, this can start to show up at high demand, like a dirty fuel filter, i.e. trunk runs fine on flat road at 50MPH, but looses power at 65mph or when going up hill at higher speed, caused by limited fuel delivery, weak fuel pump, and it will get steadily worse over time

Dirty "sock" in the tank, there is a pre-filter in the gas tank for the fuel pump, usually takes 30+ years for these to be an issue, but............depends on what "stuff" found its way into the gas tank, lol.

"Gas" pedal doesn't add gas anymore like on a carb engine, on fuel injection it is an "air" pedal, if you pump the "air" pedal you are adding more air not gasoline.
Not sure why it would feel spongy, could be TPS(throttle position sensor) is broken, this couldn't effect fuel pressure, but would cause hesitation on acceleration

Last edited by RonD; 08-10-2018 at 10:07 AM.
Related Topics
Thread Starter
Last Post
General Ford Ranger Discussion
12-06-2013 02:28 PM
Green Ranger
4.0L OHV & SOHC V6 Tech
10-02-2010 10:20 AM
Wheels & Tires Semi-Tech
01-20-2009 12:01 AM
Auto Detailing 101
02-13-2007 05:01 AM

Thread Tools
Search this Thread
Quick Reply: Sluggish starting, zero fuel pressure, but it does start

Contact Us - Sitemap - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.