89 multec injector problems
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Cruising
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89 multec injector problems
...I think its injectors. A little history on the vette. Since we have bought the car it has set more than driven. Over the last 2 years I have had to put 2 fuel pumps in due to water in the tank. When I did this each time I put in injector cleaner...I think some seafoam etc in the tank. Drove it 5 miles to the store to fill up then it sat for the next year. The car ran beautifully. I go out to start it a month ago and find the 5 mile old pump is dead....more water in tank. (now fixed) Drain all the water, new pump, fresh gas and more cleaner. She cranked and ran like crap.....I found at least 3 dead cylinders, changed cap, rotor, wires and plugs....still 3 dead cylinders. I pulled the injector wires on the injectors and found the 3 dead cylinders. Did not make any difference how the car ran at all......then, a few days later a 4th injector died...or so I think injector fails. I do have power to all the injectors.
Now my question is, Does anyone think it possibly could be the injectors or perhaps something else?
I was looking at the bosch gen 3s from FIC to replace them.
Now my question is, Does anyone think it possibly could be the injectors or perhaps something else?
I was looking at the bosch gen 3s from FIC to replace them.
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Pulling the injector wires is a good test as this will tell you if an injector is not firing, but it won't tell you WHY it's not firing. An injector test light, perhaps called a "noid" light will plug in in place of the injectors and see if they are indeed getting the correct pulse to fire.
If they are, then it's likely your injectors. Injectors that old which may have had water run through them more than once could certainly be dead. A lot of people like the Bosch III injectors, probably a good choice but you would want to verify for sure that the injectors are in fact your problem.
If I might also recommend, a car cover to keep the water out of the gas tank.
If they are, then it's likely your injectors. Injectors that old which may have had water run through them more than once could certainly be dead. A lot of people like the Bosch III injectors, probably a good choice but you would want to verify for sure that the injectors are in fact your problem.
If I might also recommend, a car cover to keep the water out of the gas tank.
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Oh, one more thing. The dead cylinders are not on the same side so that was another hint to me it was injectors and not an ECM or wiring. I'm just gonna have to break down and go check with a noid light and the fuel pressure. Its at my mother in laws house.
Last edited by roaddawg; Mar 1, 2012 at 05:05 AM.
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I'm going to check the fuel pressure this afternoon so I may as well replace the filter while I'm there. The whole fuel system had water in it. It smelled REAL bad and you could smell it when it ran. (when it ran) It can't hurt and as far as I know its the factory filter. I'm also going to check the injector wiring etc with a noid light. I'll be sure and update the thread. Today should be the day to say whether or not its injectors.
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Thread Starter
Cruising
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Thread Starter
Cruising
Joined: Feb 2012
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Well...I checked all the injector wiring with a noid light and everything checks good. (it flashed, not a steady light or no light)I didn't get to the fuel filter but only because I had 45+ PSI key on and at idle so I didn't get to involved with the fuel filter, especially being where it is. (didn't have jackstands with me.)
One thing I noticed, now it could have been just me hoping, when I first cranked it the engine fired right up and it "seemed" to run perfect for 1 maybe 2 seconds then went to crap again.
Any ideas? I'm at a loss other than replacing the injectors with bosch III's from FIC.
One thing I noticed, now it could have been just me hoping, when I first cranked it the engine fired right up and it "seemed" to run perfect for 1 maybe 2 seconds then went to crap again.
Any ideas? I'm at a loss other than replacing the injectors with bosch III's from FIC.
Racer
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When did you ohm the injectors -- before startup or after it ran for 30 seconds or so? Sometimes you can get different readings when engine is cold and when its hot (even if its only been 30 seconds). If your injectors are original and there is ethanol in your gasoline where you live, don't take the injectors off your list just yet.
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When did you ohm the injectors -- before startup or after it ran for 30 seconds or so? Sometimes you can get different readings when engine is cold and when its hot (even if its only been 30 seconds). If your injectors are original and there is ethanol in your gasoline where you live, don't take the injectors off your list just yet.
Yes, there is ethanol in the fuel here. (North central Texas) My best guess is it was setting with ethanol in the fuel, water got in tank, I replaced pump and added a bunch of additives that had METHANOL in it...
Both Berrymans and Seafoam were put into the tank.....no telling what my wife put in it when she drove it to put gas in it. I think she might have put $20 worth of gas in there so the concentration of Methanol/cleaner was pretty high I'm sure. it sat for the next year. This is when the trouble began, when we went to start it back up.
Last edited by roaddawg; Mar 2, 2012 at 03:39 PM.
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Racer
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From: Hamilton Ohio
My experience with 89 original factory injectors is that when one goes bad the ECM will shut down the engine. I mean, if a warm injector has a very low ohm reading ie: about 4, 5, 6 ohms the ECM will stop the engine. I have seen me engine run with one injector having an ohm reading of 8. When the engine was warm the reading was 17 ohms.
IF, your engine is running I'm not sure the injector (s) are failing. I switched to the FIC Bosch III injectors and they are performing very well. I have put about 300 miles on the engine since a rebuild when the injectors were changed also.
I don't know that this info really helps you any but I don't know how the ECM would let the engine idle or rev if one injector is giving you a very low ohm reading when the injector is warmed up. On my engine, if the injector/engine was cold, the engine would run just fine. As soon as the injector got warm, it would fail and then the ECM would stop the motor.
JD
IF, your engine is running I'm not sure the injector (s) are failing. I switched to the FIC Bosch III injectors and they are performing very well. I have put about 300 miles on the engine since a rebuild when the injectors were changed also.
I don't know that this info really helps you any but I don't know how the ECM would let the engine idle or rev if one injector is giving you a very low ohm reading when the injector is warmed up. On my engine, if the injector/engine was cold, the engine would run just fine. As soon as the injector got warm, it would fail and then the ECM would stop the motor.
JD
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i've got to ask, why are you getting all that water in the tank? since you changed the fuel pump (twice - ???) due to a water issue, you should have changed out the fuel filter - TWICE! any water that got past the filter, most likely got to the FPR and injectors. now i'm no FPR/injector expert, but water past the filter isn't a good thing. i kind of sounds like you have fuel pressure, so what is the pressure at idle? you indicated that you installed new plugs, wires, cap and rotor, so, hopefully, we can eliminate those components. i question all those additives in the tank - can't be that good on the system. i'd start at the tank itself, and work my way back to the injectors. if you are positive the tank is free from water (including the fuel lines), and the pump in in good operating condition, I'D REPLACE THE FILTER, then work my way up to the FPR making sure the rest of the system is free from water, and then do a detailed fuel pressure test per the FSM. if everything checks out at that point, and electrically, you are getting signals to the injectors, most likely the injectors are toast. the next step is to give Jon @ FIC a call. sounds to me like the whole fuel system is contaminated...
Last edited by Joe C; Mar 3, 2012 at 06:32 AM.
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To Recap:
- Car ran perfectly when parked, sat for about a year, bought new battery, cranked car and found water in tank and bad fuel pump, drained tank, installed new fuel pump, car ran perfectly. Put either 1 full can of berrymans or seafoam in tank with $5 worth of gas. Wife Drove to station, put $20 in tank. (Wife may have put even more additives in tank) Then it sat for the next year.
- Next year goes by I reconnect the battery and try to crank the car. Got it to run for a short period then it died, exhaust smelled terrible like bad gas. Other than running kinda rough it ran on all 8. I just figured it needed fresh gas and to be driven. Then it died. Wife said she siphoned some gas out of the tank earlier in the day. (gotta love country chicks
) I looked at her sample and it was 90% water. I refused to even think prior to this it had water in the tank AGAIN. - Drained tank AGAIN, found bad pump AGAIN, replaced pump, fresh $5 worth of gas. Tried to crank car.....now,If I remember correctly it ran good for about 30 seconds or so then it started to miss real bad. Like one cylinder dropped, then another and finally the 3rd.
- New Spark Plugs
- New spark plug wires
- New Distributor cap
- New Rotor
- Noid light test results in steady flashing on ALL injector wiring. no steady on or off state.
- Fuel pressure 45+ PSI key on and at idle (barely idling)
- Ohmed injectors after roughly 5 minutes of idling and had, if I remember correctly 17.5 ish on all injectors.
At this point I'm thinking the injectors probably have some crap in the filter baskets or the 10% ethanol in the fuel system combined with all the fuel additives have done something. Injectors are the only thing left. What troubles me about just buying injectors is I'm not 100% sure thats what the problem is. I think I'm going to pull the multecs and see if perhaps the ones in question are clogged before buying the Bosch III's