joe87tsi Posted April 16, 2009 Report Share Posted April 16, 2009 i'm new to this forum, been looking around. i have an 87 stock TBi. lately the car has been having electrical issues. at night when all the lights are on, i hit the brake for example and everything dims. as of this morning i was checking connections and smelled a little bit of fuel. i pulled the connector off the primary injector the one on the drivers side of throttle body, and there was fuel in the harness and connector on the injector. should i just replace with a new injector? Link to comment Share on other sites More sharing options...
Dad Posted April 16, 2009 Report Share Posted April 16, 2009 i'm new to this forum, been looking around. i have an 87 stock TBi. lately the car has been having electrical issues. at night when all the lights are on, i hit the brake for example and everything dims. as of this morning i was checking connections and smelled a little bit of fuel. i pulled the connector off the primary injector the one on the drivers side of throttle body, and there was fuel in the harness and connector on the injector. should i just replace with a new injector? You sure it's not just an injector seal? I would clean it off and look real close before just changing an injector. Dad Link to comment Share on other sites More sharing options...
joe87tsi Posted April 16, 2009 Author Report Share Posted April 16, 2009 i'm not sure. i just unhooked the connector. i haven't gone as fas as taking it apart. how would i go about getting the injector out? Link to comment Share on other sites More sharing options...
mikec Posted April 17, 2009 Report Share Posted April 17, 2009 Removing injectors: Look at the aluminum piece on top of the injectors - with the fuel supply hose attached to it. That part is the "injector holder" in Mitsu-speak. Wrap a shop rag around the injectors and undo the two small screws/bolts that hold the fuel supply hose to the injector holder. Undo each one about half to one turn each, then do the other one, back and forth. Slowly pull the fuel supply hose out; have the rag wrapped around the opening since gas will spew out under light pressure. Remove the o-ring on the supply hose and replace it - once it's been on the car more than a couple months it should never be re-used. Unplug the "L" shaped vac hose from the fuel pressure regulator (the little beer keg at the front of the injector holder). Unplug the electrical "clips" from the two injectors. Finally, loosen the two screws/bolts that hold the injector holder to the rest of the throttle body. Often they are mega-tight... and will strip if you use the wrong tool. They LOOK like phillips screws but are in fact something else; I forget the exact name. Most people don't have this tool anyway. Unscrew them half a turn each, going back and forth until they're sloppy loose, to avoid warping/twisting the injector holder. Lift the injector holder straight UP to remove it. The injectors may stick in it; or they could stay on the lower half of the throttle body. Either is fine. Gas will dump out so have the rag wrapped around the injectors. You'll see some rubber parts on the injectors: * o-rings at the top of each injector * rubber pads on the top of the injector - on top of the plastic part with the electrical connections. Note the "notch" in this rubber piece. * A rubber ring, with one flat side, on the bottom of the injector or stuck to the lower part of the throttle body. Note where the flat side was when you remove them - you'll need to match up the new parts during assembly. The o-rings are supposed to seal against fuel pressure. The other two rubber parts do NOT seal against fuel pressure because there should NEVER be fuel pressure pushing on them... for fuel pressure to shove on the larger rubber bits means either the o-rings have failed or, more commonly - and more expensively - the injector's internal seals have failed. Such injectors are junk. The o-rings are fatter than normal o-rings so generic ones won't replace them. The larger rubber bits are part of an injector mounting kit sold by Mitsu dealers. User "Dad" on this site (a machine shop owner) often stocks many factory bits too for good prices. Check enginemachineservice.com When re-installing the injectors, a few tips: * I had you undo all the stuff feeding the injector cover so you could clean it out with a can of spray carb cleaner. Spray the cleaner into the openings where the injectors go; you'll see some mesh screens to clean. Also clean any dried crud from the inside walls of the injector cover - that crud will scrape/damage the new o-rings on your injectors during installation. * Put a new o-ring on the fuel supply hose before installing it. Wet it with a little gas to keep it from ripping/snagging on the injector cover as you install it. If you have to re-remove the injectors in the next couple months, you can leave the fuel supply hose (and this o-ring) bolted on... that way you won't have to change the o-ring. Don't flex the fuel supply hose too much; it's old and can leak at the metal end if you flex it too much. * Put new o-rings on the injectors. Wet them with gas as well for lubrication. * When installing the larger rubber bits, aim the flat spot correctly (towards the injector). * When installing the injectors, it's usually easier to twist/screw them into the injector cover first, then lower that assembly onto the rest of the throttle body. Don't just cram the injectors into the cover... wet the o-rings with gas and twist them back and forth to prevent tearing of the o-rings. The car will take a couple seconds to start - the fuel lines are drained of fuel right now so it'll take the fuel pump 2 or 3 seconds to "catch up" - don't worry. If you replace those o-rings and rubber bits... and still find gas outside the injector... that injector is likely leaking internally and is now junk. New ones from the dealer are around $400 these days - and they sell you THE WRONG ONE for 87-89 "primary" injectors (the one with the black plastic). It LOOKS okay... but it sprays too much gas and will flood your engine which means gas ends up in the engine oil... that destroys the engine. A few folks have found Delphi injectors that work as replacements... though they need to be modded to work: 1: they're taller than stock injectors so you need small spacers between the injector cover and the rest of the throttle body. 2: they're fatter at the top - they won't fit into the injector cover. Either mill the injectors smaller or drill the injector cover larger. Several folks offer "kits" of these injectors so they are bolt-in replacements for stock - you don't have to do any milling or drilling. Use the SEARCH command and you'll find sources. mike c. Link to comment Share on other sites More sharing options...
joe87tsi Posted April 23, 2009 Author Report Share Posted April 23, 2009 thanks guys! it was just old worn out seals. thanks DAD for your help with the parts, and mikec for the how-to. Link to comment Share on other sites More sharing options...
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