The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support RTM Racing
Please Support ExtremePSI

When does fuelpump whine?

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

nek

10+ Year Contributor
832
9
Apr 17, 2009
Pittsburgh, Pennsylvania
Long story short. Last night I was driving. Car stalled and wouldn't start. Cranked fine but wouldn't start. Sounds the same as when you pull the engine fuse to relieve fuel pressure. The problem is my afpr still said I had like 40psi. For some reason I still think its fuel. My question is when does the walbro whine. Should it whine in the "on" position or only when the car is started? This is in my 2gt.
 
The fuel pump will only kick on when the engine is turning over. And pulling the engine fuse isn't going to relieve fuel pressure, you have a mechanical regulator...
 
I meant when I was installing my afpr. Pulled the engine fuse and cranked the engine on the stock regulator to relieve the fuel rail pressure. The two noises were the same. Can the fp be bad and the afpr still read fuel pressure?

Not possible for a fuel pump to quit an build fuel pressure at the same time. Now the pump motor could run but not pump fuel but it will jus whine with no fuel pumping.

Pull the fuel line to the afpr an see whats coming out. The fp can pump air if its suckin air on the in side of the pump but it wont build 40psi by a long shot
 
If you lost all your oil and the car shut off you need more than just an oil pan. Unfortunately a car will run with no oil until the lack of oil causes catastrophic failure. I'm surprised the engine turns over to be honest but you certainly have major engine damage.

Or if you still have oil in it then the no start problem is likely unrelated.
 
Having an AFPR loosely implies =>aftermarket fuel pump => Bigger injectors => link (or other tuning software)

You could use link to enable the fuel pump and listen for whine and check fuel pressure at the gauge. Or jump the fuel pump relay. Solve the questionable fuel delivery part of the equation, leaving spark and air... (and timing).

Also, gas is constantly recirculated from under the hood (heated up) and released to the tank. Depending on how your EVAP setup is you might be holding some positive pressure in the tank. Unscrew the gas cap to be sure (this may not cause the pressure to read high though on a AFPR). Mine certainly fall back down to 0 psi within a reasonable time (fuel lab)
 
I hit a big brick in the road and it was big enough for my car to lift up onto two wheels. I drove another mile. Ate dinner. Drove a couple hundred feet to a movie theater. Watched the movie. And on the way home, my car just stalled while driving half a mile out. It then started right back up. Drive anther 100 ft and it stalled and wouldn't start. Towed it home. Still cranks. Afpr went from 20 ( from siting overnight) to 40psi from crank. Tested all spark plugs good. The same thing happened to my dads truck earlier in the day. He was just low on oil but he added more and it started right back up. His truck stalled and cranked with no turn over. Added oil and it was good to go.
And my oil pan took a big dent and it put a hole right under the drain bolt.
 
If adding oil fixed your problem then all the surfaces that require oil to lubricate will be badly scored. How much oil did you have to add? Was it 100% empty?

Do a compression test and see if the motor has regular compression. If it does, maybe you didn't run completely out of oil and the stalling is due to another problem.
 
I hit a big brick in the road and it was big enough for my car to lift up onto two wheels. I drove another mile. Ate dinner. Drove a couple hundred feet to a movie theater. Watched the movie. And on the way home, my car just stalled while driving half a mile out. It then started right back up. Drive anther 100 ft and it stalled and wouldn't start.......

And my oil pan took a big dent and it put a hole right under the drain bolt.

You didn't notice a huge puddle of oil under your car from a hole in your oil pan? If I ever ran over something that caused the front wheels to come off the ground, the first thing I would do is pull over and look under the car.
 
When I get home I am going to do a compression check. Im starting to think that I melted the internals while driving it so my compression will read terrible.
I should have stopped, it was during the northeast snow storm, and I was on a date so looking under my low ass car was something that really didnt go through my head. I probably wouldnt have seen it anyways because of how dark it was and the roads were shit.
If the compression tests good, and the engine isnt seized, then something must have come loose or broke while driving it. Thats best case scenario and might have saved my engine.
Its hard to research because at no point was my engine ever seized. Every post I look at talks about the engine locking up but very little talks about the internals wearing down so quickly.
 
When I get home I am going to do a compression check. Im starting to think that I melted the internals while driving it so my compression will read terrible.
I should have stopped, it was during the northeast snow storm, and I was on a date so looking under my low ass car was something that really didnt go through my head. I probably wouldnt have seen it anyways because of how dark it was and the roads were shit.
If the compression tests good, and the engine isnt seized, then something must have come loose or broke while driving it. Thats best case scenario and might have saved my engine.
Its hard to research because at no point was my engine ever seized. Every post I look at talks about the engine locking up but very little talks about the internals wearing down so quickly.

Unfortunately just because the engine didn't seize does NOT mean it's still healthy. If you had little to no oil in the pan chances are there is a ton of bearing material all over. After bearing material makes its way through the engine it won't be long until the oil pump, turbo, cam journals, other bearings, etc. take a poop.
 
Monitoring oil pressure saves engines. Get a decent aftermarket oil pressure gauge and mount it where you'll see it often.

I have one -_-
When I started to notice my engine issue, I paid too much attention to the wideband.

Did your engine over heat during your night?

No, the engine didnt even have time to heat up once I left the movies.
 
Yes a good one my aftermarket one saved my engine when my oil return broke I had to nurse it home stopping grabbing putting oil in her from Jackson to kalamazoo, whew what a ride. The oem one is junk.
 
It didn't sound like your engine would have had time to warm up but I was just wondering. Like stated before, do a compression test and see what numbers you get. If that checks out fine, I would also maybe get some cheap oil and do an oil change after idling for a while (or look in the pan when replacing it) and see how much metal your oil has in it and that can tell you what kind of life your engine has too. I've heard stories of people going a couple days without oil in their engine before it seizes. I wouldn't start tearing it apart unless you have really low compression numbers or hear a knock. In the mean time, just save up for an engine rebuild in case the motor is bad.
 
^Yeah, Im still mixed. Basically even if its bad compression, I dont think thats enough of an issue that the engine wont even stumble to start. I currently cant get it to run so idling is still an issue. I need to test the compression and if its bad then the motors trash. If its good then I need to look into getting a new oilpan and putting in some hours this weekend to replace it.
Something tells me that because it doesnt even stumble or anything, Im beginning to wonder if its a cam / crank sensor or some other sensor that wont let it start.
The fact that I have spark and fuel with absolutely nothing besides the engine cranking should be able to give someone an idea of why it wont turn over. Even bad compression wouldnt do that I wouldnt think?
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top