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Standard Motor Products FJ503 Fuel Injector

  • Based on 534 reviews
Condition: New
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Availability: In Stock.
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Arrives Nov 11 – Nov 12
Order within 10 hours and 9 minutes
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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

Material: Stainless Steel


Brand: Standard Motor Products


Item dimensions L x W x H: 8 x 11 x 12 inches


Exterior Finish: aluminum,stainless-steel


Global Trade Identification Number: 87


Manufacturer: Standard


UPC:


Material: ‎Stainless Steel


Brand: ‎Standard Motor Products


Item dimensions L x W x H: ‎8 x 11 x 12 inches


Exterior Finish: ‎aluminum,stainless-steel


Global Trade Identification Number: ‎87


Manufacturer: ‎Standard


UPC: ‎091769780487


Model: ‎Fuel Injector


Item Weight: ‎1 pounds


Product Dimensions: ‎8 x 11 x 12 inches


Item model number: ‎FJ503


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: Nov 11 – Nov 12

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Fixed my misfire
I put it on a 2001 Silverado 4.3 l. It works well. Diagnosis: I had a p0303 error code with a very noticeable miss. It felt very much like a weak spark, and was definitely running rich, so I switched wires, the plug, and then a cap and rotor swap. I had a fouled wet plug, and got a consistently strong spark. Nothing screamed fuel injection, and I never definitively nailed it down to injection, but had read the factory system does break down with time. After a compression test showed good numbers, I decided that the injection was most likely the issue, and was willing to commit the time and money to replacing it. Since I was spending the money and effort anyway, I wanted to upgrade to mpfi, and chose this system because the reviews were mostly positive. It's a big enough job, and yes the lines are stiff and tricky to route. I used the stock mounting bracket, and the job had no surprises besides one of the plastic caps came off and it was pretty tricky to reseat the injector in it. I didn't replace any gaskets and don't seen to have any air leaks. So far, I've ran about 3 tanks of gas through it and am happy. I was hoping for improved fuel mileage but didn't get it. I did get a very smooth running engine though. I even thought the engine died a few times at stops because its so smooth and quiet compared to the old system. ... show more
Reviewed in the United States on January 18, 2022 by Wakatomika Hermit

  • 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! ... show more
Reviewed in the United States on July 27, 2023 by SRTRANDY

  • Works well in a 1997 Gmc Safari 4.3
Working well in a 97 safari. Install is straight forward following instructions. Be sure to lube the injector ends with engine oil or assembly lube. Also top gasket before putting upper intake cover on manifold. Be sure the unit is fully into the upper intake cover before bolting down. I had to pull mine up a little to seat it properly into upper cover(gently clamp a pair of needle nose vise grips to the plastic ring of unit and the gently pry unit up with a screwdriver to assure its up all the way in the upper cover). Follow the video standard has and you won't have problems with routing the tubes in the intake. Van started right up and runs smooth. About a 16 hour job with removing lower intake on these vans. Clean everything as you go and take your time. ... show more
Reviewed in the United States on June 11, 2023 by Fast Eddie Fast Eddie

  • 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

  • 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 Amazon Customer

  • Worked as intended
No concerns, worked as expected installed easily and is a quality part
Reviewed in the United States on November 18, 2023 by Matthew P.

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