|
| Search | Car Forums | Gallery | Articles | Helper | Air Dried Beef Dog Food | IgorSushko.com | Corporate |
|
|||||||
| Engineering/ Technical Ask technical questions about cars. Do you know how a car engine works? |
 |
 Show Printable Version | 
Subscribe to this Thread
|
|
|
Thread Tools |
|
#1
04-24-2010, 01:23 PM
|
|||
|
|||
|
car only starts sometimes
My friend has a 1999 ford ranger with a 4 cyl. About a month ago i went to help him with his truck not starting.It kept turning over but just wasnt firing. we kept cranking it and he even pumped the gas to see if it was getting fuel. Next We shot starting fluid into the throttle body and it fired right up.
For the next week it ran fine and then all of a sudden it wouldnt start again. A week later he went to start it and it fired up again with starting fluid. It then died again a week later. It doesnt die while driving or anything, only when you try to start it, it wont start. Is this a fuel pump problem? Im going to help him replace it but he wants to make sure that that is acually the problem before he spends the money on it. Thanks 
|
|
#2
04-24-2010, 01:44 PM
|
||||
|
||||
|
Re: car only starts sometimes
You should find a fuel pressure gauge and attach it to the fuel injector rail. If the fuel pressure is low, first would be to replace the fuel filter if that hasn't been replaced recently. Next would be to suspect the fuel pump once you confirm it is getting full battery voltage for the 2 seconds after the key is turned to the Run position.
-Rod
|
|
#4
04-24-2010, 04:41 PM
|
|||
|
|||
|
Re: car only starts sometimes
Ford usually uses a schrader valve on the fuel rail. Looks like a valve stem cap. The guage should hook right up to it. Fuel pressure gauges are usually dedicated to fuel pressure only.
|
|
#5
04-24-2010, 06:27 PM
|
|||
|
|||
|
Re: car only starts sometimes
ok. Thanks. I know i have a vacuum gauge that says it does fuel pressure as well but if its a valve it doesnt seem like it would work for that.
Thanks again
|
|
#7
04-24-2010, 09:08 PM
|
||||
|
||||
|
Re: car only starts sometimes
Quote:
__________________
1989 Caprice Classic Wagon, Olds 307 ,SMI Q-Jet, 200R4 w/Shift kit, Flowmaster 50, Hotchkiss sway bars, KYB Shocks. Jet Chip, 1989 Mustang LX 5.0 5sp convertible 1992 Camry LE 2.2 1996 Suzuki RMX250 I'm a victim of circumstance [ 
|
|
#8
04-25-2010, 09:19 AM
|
|||
|
|||
|
Re: car only starts sometimes
Not exactly sure on a ranger without looking but id say it should be 45-50psi regulated and 50-60 unregulated. If the gauge has a bleed hose, you should be able to get it to fill a 20oz soda bottle in about 20-30 seconds without any affect on the way the engine runs. Pressure should hold for quite a while before dropping off any more than 5psi.
|
|
#11
04-26-2010, 02:40 PM
|
|||
|
|||
|
Re: car only starts sometimes
ok. just did the test on it and it only gets about an ounce in about 30 seconds when i bleed out the fuel and it makes the pressure go right to 0. Im assuming that it is for sure the fuel pump. It runs at 64lbs while running and runs that constantly. when i rev the engine the fuel pressure doesnt respond at all.
Just want to make sure that you guys can confirm that it is the fuel pump. Thanks in advance for the help. david
|
|
#12
04-26-2010, 10:51 PM
|
||||
|
||||
|
Re: car only starts sometimes
I'd start by changing the fuel filter. Did you try a KOEO fuel pressure check? With the engine and key off, connect the fuel pressure gauge. Turn the key to the Run position and see what the pressure goes to. Verify that the fuel pressure jumps to spec range and remains there for at least several seconds. If it doesn't get to spec pressure or drops quickly there is a problem. Low pressure with a new fuel filter would suggest a weak fuel pump, pressure that drops quickly would suggest a leak or stuck fuel injector.
-Rod
|
|
#13
04-27-2010, 01:19 AM
|
|||
|
|||
|
Re: car only starts sometimes
i did replace the fuel filter and ran again and had the same results. I loaned the tool and i belive when i turned the key to on it held the pressure the whole time and after the car was off.
thanx
|
|
#14
04-27-2010, 07:33 AM
|
||||
|
||||
|
Re: car only starts sometimes
Has your friend noticed a trend such as it starts fine when the tank is full of fuel, but as the level gets to 1/4 or so it has more trouble starting reliably? Unfortunately you're really going to want to also make pressure measurements when the truck won't start to see what you get then. Your measurements so far don't point to fuel pump, but it doesn't sound like you were probably having any trouble currently either.
-Rod
|
|
#15
04-27-2010, 11:32 AM
|
|||
|
|||
|
Re: car only starts sometimes
he didnt say anything about fuel levels but at the same time too, i know he doesnt pay attention to those details. I know when I went to start it, it was a half of a tank of gas and on a level surface. Thats a good point though that i should try it when its not working right. I got it started and drove it to my house and has been fine since.
What does it sound like to you if not the fuel pump?
|
|
|
POST REPLY TO THIS THREAD |
 |
|
|
