Yank your Van's fuel injectors in 1 hour!

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IdahoDoug
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Joined: Fri Jan 30, 2015 9:21 pm
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Vehicle: 1988 Mitsubishi Van Wagon
Location: Coeur d'Alene, ID

Yank your Van's fuel injectors in 1 hour!

Post by IdahoDoug »

So in the midst of getting this Van ready for a 5 week trip, I smelled gas working on it today. #$%&! The #1 fuel injector is leaking. I had just put the throttle body tube back on after cleaning it and replacing the valve cover gasket. So, I gave myself 90 minutes to pull the injectors and bring them to a local EFI shop for cleaning and refurbishing. Here's how I did it.

Stick a rubber hose on the radiator drain to save the coolant, open the valve and put the hose in a bucket. About a gallon comes out. While its draining: Pull the driver's seat. Pull the floor frame thing that covers the throttle body, and of course the battery cover. Disconnect the rubber intake tube, pull the bolts holding the metal intake tube to the valve cover. Disconnect the half dozen connectors and yank the metal tube. The 4 throttle body bolts are easy and quick access. Don't disconnect the throttle cables like the book says - just use a bungee cord to the passenger side to pull it out of your way. Now you are looking at the fuel rail. The book wants you to disconnect the main fuel lines on each end and pull the whole rail out. Don't. Use two slim flat bladed screwdrivers to reach down and methodically pick at the wire bails holding each fuel injector electrical connector on. Disconnect the connectors and label either #1 and #3, or #2 and #4 (so you can put them back on with no doubt). Then disconnect the fuel rail bolts and lift it up a bit - flexing the main fuel lines and easily giving you room to grab the injectors and wiggle them off the rail. Bag them individually with 1-4 labelled on the bags for the injector guy. Done. I made it to the shop with 15 minutes to spare. The #1 injector's internal red O ring was trashed - coming off in shreds and obviously the source of the leak. I will get them back cleaned, with new filters, new seals and O rings and a printout of their flow before and after. The engine will run much more smoothly and with more power I expect.
ELPATO
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Yank your Van's fuel injectors in 1 hour!

Post by ELPATO »

Thanks for the info on this...you didn't mention it in your description...but did you relieve the pressure in the system prior to pulling the injectors? Or is there some trick to get around that process? I have been reading over the process in the manual on my 89...and your process sounds much quicker. Also curious once I have reinstalled the new Fuel Injectors...is it necessary to bleed the system of air...or does simply cranking the engine over do that? Thanks for the help!
IdahoDoug
Posts: 112
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Vehicle: 1988 Mitsubishi Van Wagon
Location: Coeur d'Alene, ID

Yank your Van's fuel injectors in 1 hour!

Post by IdahoDoug »

On bleeding the pressure - it will bleed off a bit of fuel. Just use common sense safety knowing you will have a flammable substance dripping for a bit. Disconnect the battery, have a fire extinguisher on hand, attention to fumed (not inside a sealed building), etc. As for air - nothing to worry about. The fuel pump will push air right through very fast. Nothing to do for you but turn the key.
ELPATO
Posts: 13
Joined: Wed Jan 11, 2017 5:47 pm
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Vehicle: 1989 Van/Wagon
Location: SF BAY

Yank your Van's fuel injectors in 1 hour!

Post by ELPATO »

When you were cleaning the throttle body tube and then noticed your #1 fuel injector was leaking....was there something about your engine performance that made you want to clean the throttle body tube? Mine has been running fine...but I do notice when its warm outside my idle becomes erratic and unstable (it doesn't cut out completely but it feels like it will)...still have power when throttled up and driving...there is just a lot of sputtering and unstableness when at idle. I'm having trouble putting a finger on it...any thoughts? I do have the manual...but I feel like the troubleshooting section isn't all that great...just looking for others input...

Thanks!
IdahoDoug
Posts: 112
Joined: Fri Jan 30, 2015 9:21 pm
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Vehicle: 1988 Mitsubishi Van Wagon
Location: Coeur d'Alene, ID

Yank your Van's fuel injectors in 1 hour!

Post by IdahoDoug »

I don't recall any issues specifically but do remember I was having idle issues - too high I think. From past automotive projects, throttle body cleaning - especially the throttle valve cleaning where it seats and the edge of the butterfly valve itself - has paid dividends. It did here as well. Small variations in the amount of air leaking past the valve from accumulated crud will make the idle unsteady as it constantly hunts to adjust itself. Same for off idle acceleration such as in a traffic jam where you're barely opening the throttle over and over to incrementally adjust speed with cars all around you at a walking speed. So it's worth doing. Be sure to use a fuel injector cleaner vs a carb cleaner. The former are slightly less aggressive and won't damage sensors where carb cleaners are from the sensor free days where they could be aggressive. Take an old toothbrush and a lighter or gas stove flame and bend the toothbrush to let you get in there and clean the edges of the butterfly valve well, etc. A little diligence goes a long way here where you're trying to get crud out of tight spots.
ELPATO
Posts: 13
Joined: Wed Jan 11, 2017 5:47 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1989 Van/Wagon
Location: SF BAY

Yank your Van's fuel injectors in 1 hour!

Post by ELPATO »

So I took the van into a mechanic to help troubleshoot my rough idle situation (I haven't had time to open things up and troubleshoot on the engine)...I'm also still using the van as my daily driver to a from work so its making things a bit difficult. One observation the mechanic made was that I was leaking coolant from the coolant temp sensor and a freeze plug. I scored a replacement coolant temp sensor but looking through my manual...I see nothing about freeze plugs???? Does anyone have a picture handy of where exactly these plugs are? And is it common for them to eventually start leaking?? My idle situation is still heat based....so in the morning...it starts up fine...but as the day heats up...the idle becomes horribly all over the place....so much so I need to put it in Neutral and rev the idle to keep it from stalling. This whole time I've been focusing on Fuel Injector issues...but I don't understand the heat component of my problem? Any recommendations on the best way of troubleshooting this would be great??
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