2G How to diagnose bad Injector?

[clbailey]

Im getting a cylinder misfire and I've been smelling gas alot more than normal so I'm assuming I have a stuck injector. Besides pulling it out what other ways can I check it? I have and know how to use a multimeter.

 

[ramsack]

Then take a shower and put on some deodorant.

Kidding aside, what are you smelling?

 

[BoostedBeaver]

If you are receiving a cell, then you need to read it!!! If you are having a miss in a cylinder, the computer will tell you which one it is.

You can test resistance of the injector by unplugging the connector and using your multimeter. Here is a video where you can find the resistance specs. Instead of measuring through the wire, just unplug the injector plug and prob the two tabs.

http://www.youtube.com/watch?v=lQHl-ikqI2E&list=UUd8JfwGxmRb5P7nMVRzSPng&index=4&feature=plcp

If you would like to clean them, here is a DIY method. It does require an air compressor and a few other tools, but you can clean your injectors on the bench. If not you can either send them off or try some in the tank version.

http://www.youtube.com/watch?v=kzYx30fVi9I&list=UUd8JfwGxmRb5P7nMVRzSPng&index=3&feature=plcp

My video was inspired by this one.

http://www.youtube.com/watch?v=3mnA0cnXckg&feature=channel_video_title

Again if you are receiving a cell, read it and it will make life easier.

Robert

 

[ramsack]

A multimeter is going to tell you nothing about an inductor which intermittently fails. Measuring the resistance of a coil is a nearly useless way to find intermittent problems. You would need to remove the injector and test it as it functions...by pumping fluid to it and pulsing the injector, and see if it works every time. Coil resistance will tell you nothing about how the solenoid inside is functioning.

 

[clbailey]

Its p0301 cylinder one. I already knew that but I'm fairly certain its the injector. Previous owner left a bunch extra in the car when I got it.

 

[BoostedBeaver]

Checking the resistance would just check the coil and prove weather that is good or bad. It is a rather simple test that could be done in the car that is why it is recommended first. The next step would be to clean them to test their functionality. If you have the tools, the cleaner above will do exactly that. With the knowledge of which cylinder, you can focus on that injector for the testing. Hope this helps.

Robert

 

[ramsack]

A resistance or continuity test does not always indicate whether it is bad or not. A coil's winding can be cracked but still have continuity, but as soon as engine vibrations hit it, or heat expands it, things will start going haywire. It can be a quite maddening situation. Cleaning would be the easiest thing to do at this point, and there is no bad in at least keeping injectors clean.

 

[clbailey]

I had to put a new fuel pump when I got the car. When it sat I had to pull the pump again because it sucked up gunk in the tank because the previous owner let the car sit for 3 years without gas in it. I'm willing to bet some stuff got past the pump hat and the filter. I will clean them because it came on randomly I checked it and cleared it then it popped back up a day later.

 

[BoostedBeaver]

A resistance or continuity test does not always indicate whether it is bad or not. A coil's winding can be cracked but still have continuity, but as soon as engine vibrations hit it, or heat expands it, things will start going haywire. It can be a quite maddening situation. Cleaning would be the easiest thing to do at this point, and there is no bad in at least keeping injectors clean.

I was not saying that this is the end all test. I was simply stating that it was an easy check that could be made to point out a problem. If it passes this test further investigation must be done, but if it fails this simple test, you have an answer with the cost of only a few minutes.

Cleaning is a great idea but depending on the OP's situation and tool accumulation, he may not be able to do this himself. I would still check the injector for resistance as it only takes a few moments and you have the tools. I would then do the leak test to insure that you do not have a leaky injector, again this can be done with everyday tools. Then if cleaning is something you would like to consider, you can build a cleaner or send them to a company like FIC for cleaning. Keep us posted on what you find.

Robert

 

[clbailey]

Well I figured out the problem.

Ive been using Mobil 1 since I got the car. Which was 2 oil changes ago. One was as soon as I got the car with seafoam and the other was a few weeks ago. Im getting oil seeping into the plug galley fouling the plug.

Add that with a Walbro 255 without an AFPR yet, and that explains the fuel consumption as well as the smell.