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Standard Motor Products FJ503 Fuel Injector

  • Based on 546 reviews
Condition: New
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Availability: Only 6 left in stock, order soon!
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Arrives Thursday, May 7
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Features

  • Country Of Origin : China
  • The Package Height Of The Product Is 3.37 Inches
  • The Package Length Of The Product Is 2.0 Inches
  • The Package Width Of The Product Is 1.43 Inches

Description

Standard Motor Products FJ503 Fuel Injector

Manufacturer: ‎Standard


Brand: ‎Standard Motor Products


Model: ‎Fuel Injector


Item Weight: ‎1 pounds


Product Dimensions: ‎11 x 12 x 8 inches


Item model number: ‎FJ503


Exterior: ‎aluminum,stainless-steel


Manufacturer Part Number: ‎FJ503


OEM Part Number: ‎FJ503


Date First Available: October 10, 2007


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, May 7

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Top Amazon Reviews


  • These work great and fit just like OEM
I just installed this on my 2001 Chevy S10 Blazer. The stock 22 year old spider injectors finally started leaking, and it was hard to start the car. So, this Standard Motor Product injectors fit just like OEM. I did not have to modify anything or come up with clever ideas to make it work. Also, the car now starts very quickly and it runs buttery smooth. Also, the car now gets much better gas mileage. While I was doing this, I also swapped out the lower intake gaskets with some metal Mahle gaskets. This whole project took me about 6 hours. Very easy, it’s just a lot of connectors to remove and a lot of stuff to move out of the way. Highly recommend these injectors! Update: I installed these on my truck July 2023, and now it’s Dec 2024. It’s been over a year, and I’m very happy to say that these injectors are still working great after over a year! Highly recommend! ... show more
Reviewed in the United States on July 27, 2023 by SRTRANDY

  • Easiest difficult job ever.
Worked as intended. I did this job with the help of Youtube. I was freaking out the whole time. READ the instructions sheet. The "legs" are stiff so heating them up might help them bend easier. Use motor oil as lubricant, NOT silicone, you WILL need to rotate the connectors at the top of the injector to get the plenum back on. You DO NOT need a new bracket. For god sakes don't be a shmuck, don't buy a new bracket. I didn't buy one and the car's running now. How did I diagnose the problem and thus chose to buy this part? I would turn the engine over buy it wouldn't start, there would be white smoke from the throttle body when I opened it with my hand, and there was a gasoline odor in the air. Fuel pressure was present at the valve near the top back of the plenum. Need tips for doing the job? Use motor oil as o ring lube, read the instruction sheet, and use paper towels to block off the intake ports, if anything falls in there you're going to have a terrible and long day. Buy replacement gaskets too. ... show more
Reviewed in the United States on February 27, 2015 by Adrian

  • nice unit, great deal
Installed on a 1998 GMC sonoma 4.3 w code v6 SLE pickup. Very nice unit with fantastic instructions. Does not come with upper intake cover gasket like another reviewer stated. They must be thinking of the o ring around the fuel inlet that sticks through the cover. I reused my old one which should be the case for most people. But if you want to be sure, pick one up. It also does not come with the mounting bracket for inside the intake manifold but fits the stock one no problem. Instructions make it a breeze to put in place of the old unit and it works great. My truck now runs as smooth as when it was new. Amazon has an amazing price on this piece and I am very happy with purchase. ... show more
Reviewed in the United States on April 20, 2011 by M Costa

  • perfect replacement for my 2004 4.3 vortec
i said install was easy,guess it depends on your level of ability,mine was in a chevy astro van and still i wouldnt say difficult,but i work on everything i own anyway,thought it would come with a new bracket,didnt,but it fit my original anyway,only weird part was trying to fold the legs of it to fit the bracket for injectors on 3 and 5,afraid i would break it but it works if you take your time and read the instructions and or watch a you tube video,replace the injector plenum gasket also if its original because it will not be reusable,if your unfamiliar with what your doing,mark each injector with the cylinder # to insure you put it in the right hole before you click them in as to avoid damaging them they are hard to get back out! ... show more
Reviewed in the United States on November 17, 2019 by tipoblanco

  • Do NOT buy it perduces too low of pressure
Bought for a replacement for a 2001 S10 with the 4.3l motor. I also replaced some fuel lines, as well as the fuel filter. The truck kept stalling while driving, especially on the highway, with no warning at all. So at 65 MPH the truck shuts off. Being disabled I am limited to doing physical repairs. I also had some O2 sensor issues so I ended up storing the truck in a storage unit for about 2 years thinking the O2’s had something to do with it. So only about 100 miles on the motor after installing the spider and had to park it because of the pressure issue. At the time of installing this spider, my old fuel pressure tester showed 44-49psi output. I figured that was fine. I did not have the factory GM service manuals at that time. (got them on Ebay later) With very little income I bought fuel testers and even a fuel gauge to mount on the dash the following years. The gauge showed the same as the new fuel testers. This spider injector puts out 52psi, at BEST. The motor REQUIRES 63 PSI per the specs from GM (at the schrader valve). The only way to get up to 50psi is to turn the key 3 separate times to prime the system before starting. It will go: 1st turn 44psi, 2nd turn 47 psi, 3rd turn 50psi readings. When driving pressure increases slightly to 52psi. At 65mph and in overdrive it reads 49psi on the highway, well below the specs from GM. So the motor just shuts off when driving like you turned the key off. No sputter or any warning, just complete shut off. VERY DANGEROUS. So you have to coast to a stop on the shoulder of the highway and then restart the truck. Sometimes taking more than a half dozen tries to get it to fire up again. I then found this specific amazon part mentioned on forums and people having the same issues of stalling or even no start conditions. The pressure regulator appears to be the issues. People that replace the regulator then have pressures in the high 50 to 60 PSI range. Now that I have got GM service manuals and learned about this system (I’m used to pre 1980’s carb systems), it is too late to return it. COMPLETE WASTE OF MONEY. So I have to tear back into the motor to replace the regulator just to see if this spider will actually put out the required 63 PSI output. So new gaskets and regulator just to make this thing work. DO NOT BUY this junk spider. If you do, look up your PSI requirement and test it the moment you install this junk spider. I guarantee you it will not put out enough pressure if your system needs higher than 50psi. ... show more
Reviewed in the United States on December 23, 2022 by Kriss L

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