Hi All,

This is my first post on this forum and I am hoping someone can help me out. I have a 99 Diamante with 115k miles and had no issues with this car in the past 7 years until now. The car started running very rough and I noticed a lot of smoke coming from the exhause that smelled very heavy of gas. I anticipated that it was probably a fuel injector stuck open. I took it in to a Firestone shop to have it diagnosed and they found that two of the back injectors are bad. They ohm'd them all out and 4 were within spec which I think is about 17 ohms, and 2 were between 40-50 ohms. They wanted $2000 to fix it which is absolutely ridicoulous and I figured I would try it myslef. They wanted $300 a piece just for each injector (I found remanufactured ones on ebay for $35!). So I have a few questions:

1) Does their diagnosis make sense that the two that ohm'd high are shot and need to be replaced? Or can they just be cleaned/reconditioned some how?
2) I know I have to take off the plenum to get to these back injectors but since I have never replaced fuel injectors before, is there a standard procedure to follow when removing the old injectors and installing the new ones. Do I need any special tools for removing/installing the injectors? How do they come out? Is there anything special I have to do after the new ones are in?
3) The guy at Firestone said it is possible that since both injectors were stuck open and dumping fuel into the engine that there could be some other residual damage after the injectors are replaced How likely is that? I do plan on replacing the spark plugs and changing the oil at a minimum. Anything else I may need to replace due to this?

Thanks,
Nick

 

injectors sticking open on diamantes is kinda common. It is NOT due to an electronic failure, though. They merely stick. Fuel type seems to be of major influence on this.

the only other likely damage (depending on how long youve driven it) would be a melted/ruined catalytic converter on that bank.

 

Thanks for the response Manybrews. So after I pull the injectors, is there a way to get them "unstuck".

I'm guessing that I probably drove 1-2 miles with the injectors stuck open (tons of smoke poring out of the exhaust when I drove it). Regarding potential damage to the catalytic converter, how would I know (what would the symptoms be).

 

I'm in major need of some help. To follow-up on my previous post, I replaced the back 3 injectors with remanufactured units, changed the plugs, changed the oil/filter and put everything back together and it temporarily worked. I drove the car and for about 2 blocks everything was fine. Then it went back to the exact same thing (running rough with lots of white smoke with heavy gas smell). I ohm'd out the old inectors that were taken out and they were all between 15-16 whereas Firestone told me two were 40-50 ohms. I think they ohm'd it at the main connector since there would be no way possible for them to get to all 3 back injectors. What could be going on here? Although possible, it seems unlikely that the new injectors are bad right out of the box (especially since they temporarily worked). Could there be bad gas causing something to happen with the injectors? Anyone have any ideas? I just threw $300 at this car thinking it would solve the problem with no success and don't want to spend any more money on this car without being confident what the problem is. Any help would be greatly appreciated.
Thanks,
Nick

 

One more piece of info. I just ohm'd all the injectors at the one connector they all come to and they all came within spec (around 15.3 ohms). Now I am really baffled. Please help.

Nick

 

the electronic portion is not the problem. If its stuck or clogged, the resistance isnt going to change.

sounds like you still have at least one stuck open. I do NOT recommend aftermarket rebuilds, because they're usually junk.

 

How would I know if it is stuck open? Is there any way to get it unstuck?

I took it back to Firestone today to try to diagnose and they came up empty handed and could only offer to suggest that the ECM may be bad and to check it. Does this make any sense?

Nick

 

no, no, no.. Its NOT an ecm.

either you still have a leaking injector, or something isnt assembled correctly. Take it to mitsubishi, not to the idiots at firestone.

 

is the check engine light on?? that will give you as good indicator to what it is. you really need a scan tool to look at all the data the ecm has to offer for a correct fix. a few months ago i had a diamante in the shop doing almost the same thing. after looking at the data with our scan tool the temp sensor was reading negative 40 degrees. that means the pcm was dumping fuel into the system to get the engine to operating temperature. a $40.00 sensor caused all the probelms for this guy, and he had to replace both converters due to the raw gas got into them and they melted. that was almost $2,000. take it to a mitsubishi shop now, to get a proper diagnosis. hopefully it isnt to late.

 

2001 Mitsubishi Diamante LS

Im having the same problem as far as white smoke coming from exhaust and gas basically pouring out of the exhaust. I have changed the pcv valve, coolant temperature sensor, all spark plugs, fuel pressure regulator, and a fuel injector with no change in the matter whatsoever. at this point the car has been sitting on bricks all tires flat from the cold weather in my driveway for 3 months plus. i can go through a gallon of gas in less then 30 seconds, i need help i am out of ideas and dont want to keep throwing parts at it to get it to work... please help...