Good way to clean fuel injectors? Also, DSM pro advice needed --->

[mhuffman]

Is there a better way to clean fuel injectors than to just run fuel system cleaner thru the system? I've already run a good cleaner thru and the problem hasn't gone away.

I am getting a bad misfire above 4k rpm's at full boost, perfect driveability when i'm not WOT. I recently put in NGK plugs and Accel wires so those shouldn't be the problem. I've also done a pressure test and i dont have major leaks. I'm not throwing a CEL, and i get good (25+) gas mileage. 91 FWD turbo... The car spins tires in second gear so its not like its low on power. But it drives terrible at WOT high rpm ever since i did my 2.5" cat and 3" DP.

I'm thinking it's either my ignition coil or one or more of my fuel injectors. Any ideas?

 

[xioca]

I'm not calling you a lier. And I'm pretty sure if I remember correctly that the carb cleaner will drip through the injector by gravity alone, making it seem that it is open.

 

[pur97tsifwd]

you should run seafoam threw it just take out the spark plugs and drop a little in there and let it sit for a while put it in the oil and fuel then put spark plugs back in and start it up then after that run it threw a vacuum line it really does wonders on cars cleans them out i do it every few months makes me feel better about my engine

could be fuel cut also

 

[luv2rallye]

Your not going to get .5 amps from a AA battery though. And according to my fsm the injector resistance is 13-16 ohms at 68*f and the resistor is 5.5-6.5 ohms at 68*f. those together averaged out come out to around 20 ohms at 68*f. Ohms law says that 12v / 20 ohms = .6 amps. That would be the normal current draw to operate the injector. So at 1.5 volts you get 1.5v / say 14 ohms (no resistor) = .10714 amps. to power the injector with. Not likely to work very well. It just might, but it does'nt look like it would very well.

BISHILVR you've got your facts incorrect!
(I was going to let this slide but you are misleading people with too many invalid facts and conclusions.)

1) The injector coil resistance for the 4g63 turbo (1g or 2g) is 2-3 ohms @ 68F!!! Look in a real Mitsu manual and you will see this. I even measured mine and it's 2.3 ohms. Your 13-16 ohm figure is for the 2.0 NT or the 2.4L engine!

2) A 1.5V AA battery can easily put out .5A for many minutes (obviously not for hours of course). I connected a 2 ohm resistor to a new AA (Energizer) battery (which is of course 0.75A draw initially) and after 1 minute, it only dropped 0.09V (to 1.41V which is still a 0.70A draw). Your mentioned 0.5A draw would last much longer with much less voltage drop. A 2-3 ohm injector would only draw 0.5-0.75A max. Now obviously it can't keep the full 1.5V, but you don't need 1.5V to operate the injector since it operates on current not voltage (also see the next item).

3) Injectors don't need their full (or normal or average if you want) current draw to open when they are on the bench where there is no fuel pressure to hinder them and no need to open fast like would be true in a running engine (which is why they drive them with higher currents). I haven't tryed it but I can easily see them opening with only 0.5A on the bench and so have no problem with that article on cleaning. The only time I see them needing higher currents on the bench would be if they're stuck. In fact in one of your own later posts (#20) you state that 0.32A opened the injector!! You just proved that a AA battery will then open them since a AA battery can put out over 1A (see item #2). You obviously in your experiment with the AA battery either didn't have a fresh one, had a stuck injector, it was open and you didn't know it, or you didn't use a stock 4g63T injector.

 

[BISHILVR]

It was a stock injector, I got my info from the factory service manual, and the battery was'nt capable of putting out .5 amps. I tried several and even dead shorted them, they would'nt put out .5 amps. If what you say is true then why would'nt mitsu use a 5 volt source to drive the injectors instead of 12v?

This SURE looks like a factory manual to me?? And if you look over the page you will see that they are testing the TURBO injectors on this page including the injector resistor!

 

[steve]

If what you say is true then why would'nt mitsu use a 5 volt source to drive the injectors instead of 12v?

You claim to have a EE degree, why do you think they don't run the injectors off some other voltage source than battery.

Like luv2rallye, I measure about 2.3 ohms DC resistance for my 450 injectors. The NA injectors are high impedance in the 12+ ohm range.

I'll go back again and see what it takes to open the injector but I remember doing it with a couple of standard cells to see if it would for testing.

Steve

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[BISHILVR]

I remember doing it with a couple of standard cells to see if it would for testing.

A couple of standard cells was'nt part of this question. A single AA battery is supposed to open the injector. According to your 2.3 ohm claim for your injectors, the AA battery would have to put out 653ma or .65 amps. to operate the injector. At 2 ohms the AA battery would have to put out around .75 amps to operate the injector. The question I posed was a uhmm, rhetorical question. Maybe you should get some sleep

 

[steve]

A couple of standard cells was'nt part of this question. A single AA battery is supposed to open the injector. According to your 2.3 ohm claim for your injectors, the AA battery would have to put out 653ma or .65 amps. to operate the injector. At 2 ohms the AA battery would have to put out around .75 amps to operate the injector. The question I posed was a uhmm, rhetorical question. Maybe you should get some sleep

Yes, that's the way the numbers come out but there is also the effective series resistance of the battery to take into account which may be part of what your trying to get at. And there is the emperical data. I just grabbed a fresh duracell AA and a blue top 450. Open circuit voltage is 1.6v. Not having 4+ hands I didn't measure voltage under load but I did measure the current draw of 430mA from a single AA opening the injector. You can deduce what the loaded voltage should be.

I had a column of cleaner above the inlet but no real pressure and under power it passed through the injector while it didn't leak with the battery disconnected. I think that proves xioca statement. A single Nicad or Ni-MH cell could deliver higher currents than the Alkaline Duracel

There are much better ways to power the injectors for cleaning but it did work.

Steve

 

[luv2rallye]

The attached image in post #32 does not look like it's from a real Mitsubishi factory manual. Mitsu manuals aren't layed out like that with the OK inside a circle and the column on the right. And it obviously has the wrong value listed for the turbo injector resistance (they mistakenly used the NT value). The image in post #33 is from a Mitsu factory manual.

 

[BISHILVR]

The attached image in post #32 does not look like it's from a real Mitsubishi factory manual. Mitsu manuals aren't layed out like that with the OK inside a circle and the column on the right. And it obviously has the wrong value listed for the turbo injector resistance (they mistakenly used the NT value). The image in post #33 is from a Mitsu factory manual.

Trust me dude, its a factory manual, I will take a pic if it makes you feel better. Look at the page number at the top, who else numbers their books like that?

The image in post 33 has been photoshopped or otherwise tampered with! Look at the ohms symbol's. Nice try though, off you go.

 

[PieEyedPiper]

The image in post 33 has been photoshopped or otherwise tampered with! Look at the ohms symbol's. Nice try though, off you go.

You don't think it was possibley just printed like that? Have you ever read a newspaper?
I see no reason for anyone here to try and fool you.

 

[steve]

The image in post 33 has been photoshopped or otherwise tampered with! Look at the ohms symbol's. Nice try though, off you go.

Just grab a Manual CD and look for yourself.

It was in fact photoshopped since that's the easiest way for me to cut and paste an image from the pdf into a image for posting. The artifacts your whining about are from the original scanning process used in making the manual CD.

I wasn't about to grab my original manual and scan the page just to prove your clueless. You keep doing that ok by yourself.

I really can't believe you don't know that the turbo cars use low impedance injectors and your either misusing your manual or it's in error.

Steve

 

[jumpfroggy]

I know I'm just piping in here, but does it really matter what theory and what ohms are behind all this? The real question is: does it work, and is it worth doing. We have a person claiming that it worked for them (hooked up battery, that opened it up, and the carb cleaner flowed through the injector).

So the real jist should be this: who else has tried it, and what were your results? Anything else is interesting, but maybe not as useful.

 

[1gcrazy]

Wow, THATS annoying....

Just for the record....I'VE DONE THIS AND IT WORKS. Not like it would matter anyways because...well nevermind. I'll let the wisemen battle this one out...

 

[luv2rallye]

Trust me dude, its a factory manual, I will take a pic if it makes you feel better. Look at the page number at the top, who else numbers their books like that?

Not Mitsubishi! Mitsu uses a group number, sometimes followed by a single letter, followed by a dash, followed by the page number within the group. Like 13A-252, or 14-79, but not 14MI-167. And it would never have an obvious spec error like injector resistance. I believe your manual is some aftermarket one like Chilton's, AllData, Mitchells, etc and your FSM probably stands for Field Service Manual not Factory Service Manual. What year is it for and what exactly does it say on the cover?

I have attached an actual scanned in (not photoshopped) pages of this injector check from my 1999 Mitsubishi Eclipse Service Manual which I bought right from the Mitsubishi dealer (cost $120) when I bought my Eclipse.

But as jumpfroggy says "does it work" is the real point and I believe both Steve and I have proven it does. (All the ohm stuff was to point out your injector resistance error and to prove an AA battery will work both mathmatically (ohms law) and with empirical evidence (injector tests with AA battery) as already done by at least 3 people now).

 

[xioca]

Hell dude this is ridiculous, I'm going to make a little video clip of it tomorrow just so it can be proved it works... and isn't photoshopped.

 

[1gcrazy]

Hell dude this is ridiculous, I'm going to make a little video clip of it tomorrow just so it can be proved it works... and isn't photoshopped.

Please do. If you dont I will...

 

[Dream On]

This is crazy. Why would people sit there and photoshop all of this stuff? Just to prove you wrong? In your scan of the FSM, I don't see anything about them testing turbo injectors. I think it's just for the NT's, which would explain the difference.

 

[BISHILVR]

Here is the REAL service manual that the info came from:

 

[BISHILVR]

This is crazy. Why would people sit there and photoshop all of this stuff? Just to prove you wrong? In your scan of the FSM, I don't see anything about them testing turbo injectors. I think it's just for the NT's, which would explain the difference.

Its pretty obvious that its not, they dont even make a non turbo only book that I know of.

 

[mhuffman]

could be fuel cut also

I still have the problem even after regapping the plugs. I used third gear about 4/5 throttle until 6k rpms and has no problems, but when i did WOT i had a complete, abrupt power cutout. Is this fuel cut? If so, why am i getting it?

 

[oldman]

If you truly have a FSM, your 93' edition is wrong, misprint, or it's a knock off (a poor one at that). Post your chapter 14 index.

Regardless, your information is wrong, my FSM matches steve's perfectly, question is, why is your DSM different from everybody elses.

I still have the problem even after regapping the plugs. I used third gear about 4/5 throttle until 6k rpms and has no problems, but when i did WOT i had a complete, abrupt power cutout. Is this fuel cut? If so, why am i getting it?

looks like everyone forgot about you!!! Let's start from the begining.

I've also done a pressure test and i dont have major leaks.

Tell me about your leak test.

1. Where did you put the tester?

2. What are you using to pump air into the intake tract?

3. If compressor, what psi did you set the compressor regulator to?

4. What was the maximum psi shown on your boost gauge during the leak test?

5. How long did it take for it to bleed down to zero after you stop pumping?

6. Tell us about the minor leaks.

 

[BISHILVR]

Nice try but it came right off the shelf at the dealerhips library, better than the public version seconds that everyone else buys.

 

[oldman]

Like I already said, either it's a knock off, or a mis-print, I don't know what you're arguing about, the debate is over, now stay on topic or move on.

 

[BISHILVR]

Well its definately a real manual I know that. Why do they call you Oldman if your only in your 20's? Just curious.

 

[oldman]

Well its definately a real manual I know that. Why do they call you Oldman if your only in your 20's? Just curious.

Sorry, I don't dance, maybe steve will. I'm here to help bring the thread back on topic, any more off topic posts will be deleted and warned.