94 accord ex no power to fuel pump
#1
94 accord ex no power to fuel pump
I have been fighting this car for the last couple months trying to fix this. I turn the key, the starter engages and turns but the car will not fire. Spray starting fluid in the intake & it fires.1 in about 100 times the car starts and runs well, but D4 blinks. Jumped ecm to get 14, AIC code. Removed & cleaned AIC but doubt the idle control is the issue as the car doesn't even get the chance to idle. Replaced PGM FI relay hoping for quick fix but got no change. Tested for power to the fuel pump at the fuel sending unit & am getting no power. Have checked all driver side fuses & they are good as well. Vehicle has gas in it. Where else is power to the fuel pump regulated?
#2
What wire color are you checking at the fuel sending unit? Are you using a test light or a volt meter? Are you testing for voltage when the key is in the II position, or when you try to crank the engine?
#3
Have check to see if you have any fuel pressure? Do you have a wiring diagram? If it's electrical you will need that and you may be able to get one at your local library. Most pumps have their own dedicated fuse under the hood.
#4
It's real easy to be fooled by lack of power at the fuel pump connector in the trunk. When keyswitch is turned to On, the fuel pump only stays on 2 secs, so unless you had a helper you would always find no power when you checked.
I had a "sticky fuel pump" on my 94 EX. It would run most of the time but would occasionally stick and refuse to start. I finally stumbled on a temporary fix until I replaced the fuel pump. "Hammer" the pump w/ repeated on/off/on/off,... until you hear the fuel pump buzz in the tank. Once you hear the fuel pump, it should start.
It very much appears to be fuel delivery. Since you've replaced the MFR, the most likely component is the fuel pump. But check and be sure.
good luck
I had a "sticky fuel pump" on my 94 EX. It would run most of the time but would occasionally stick and refuse to start. I finally stumbled on a temporary fix until I replaced the fuel pump. "Hammer" the pump w/ repeated on/off/on/off,... until you hear the fuel pump buzz in the tank. Once you hear the fuel pump, it should start.
It very much appears to be fuel delivery. Since you've replaced the MFR, the most likely component is the fuel pump. But check and be sure.
good luck
#5
I had my dad testing the black/yellow wires coming from the sending unit with a light. We tested both the key position II & while turning almost to Start. If I turn to start & allow the starter to run, I would assume the fuel pump should get power the entire time, correct? I've got the wiring diagram from the Haynes book, but I'm the first to say, I'm not the best at interpreting those things. I'm going to spend some time with it tonight, as it appears the power steering is failing in my Bimmer. The Honda can no longer be a garage ornament. I would go ahead & replace the fuel pump, but am really wanting to avoid dropping the fuel tank for what may not be the problem.
#6
If you've confidently confirmed that keyswitch is supplying voltage for 2-3 secs to the fuel pump connector, and car will not start, I think you can safely remove the fuel pump.
Did you try the "Hammer" routine? I think the failure mode for these pumps is a "flat" spot in the fuel pump motor. When you bump to a new position it may finally start.
I found removal of the fuel tank not too bad a job:
1) Elevate car safely on jack stands (all 4 wheels!) as high as possible.
2) Disconnect electrical connections and wiring in the trunk and feed down through the trunk opening.
3) Disconnect the fuel fill connections and vent connections.
4) Lower the tank by removing the straps (tank may be stuck to body and require some prying). A large box or short stool for support is helpful to partially elevate the tank and allow remaining connections to be accessed.
5) Disconnect fuel supply/return/vent lines and remove tank.
Shop manual was helpful, but Item 2) above was much easier than shop procedure.
good luck
Did you try the "Hammer" routine? I think the failure mode for these pumps is a "flat" spot in the fuel pump motor. When you bump to a new position it may finally start.
I found removal of the fuel tank not too bad a job:
1) Elevate car safely on jack stands (all 4 wheels!) as high as possible.
2) Disconnect electrical connections and wiring in the trunk and feed down through the trunk opening.
3) Disconnect the fuel fill connections and vent connections.
4) Lower the tank by removing the straps (tank may be stuck to body and require some prying). A large box or short stool for support is helpful to partially elevate the tank and allow remaining connections to be accessed.
5) Disconnect fuel supply/return/vent lines and remove tank.
Shop manual was helpful, but Item 2) above was much easier than shop procedure.
good luck
#7
I just got through fixing a similiar issue with my 93 accord. My fuel pump was not kicking on when turning the key to the on position. I pulled the PGM FI relay and tested it, it was fine. I then put a jumper wire between the black/yellow and yellow wire(not mine is a 93, your may be diff). This provided voltage to the pump and the pump did kick on. This told me the pump would try to run if it had direct voltage. Then i noticed one of the wires (yellow blue) in the connector to the relay had broken. I fixed the brake and that restored power to the fuel pump - car runs fine now. So before you tear into the pump, you may want to check all your wires coming into your connection to the relay.
#8
Really appreciative of all the input. I got a new fuel pump in it last night & so far, that seems to be it. I don't think I'll ever understand why Honda put an,access panel for the sending unit but not for the pump. That tank is not easy to put back in as a one man job. Again, thanks to all for the help
#9
I too had this similar issue about two months ago, intermintent no power to pump, replaced relay no start, checked all wiring from fuel relay to pump checked ok, went to check wiring from ecm to relay found passenger floor soaked with water, my ecm had an intermitent open causing the fuel pump not to run when key was turned on, luckily I found an ecm for $30 bucks at a local scrap yard, windshield was leaking at top and running down passenger a-pillar, resealed windshield, shes been running fine since
anyways, ck nthe wiring from ecm to relay for continuity, if all wirnig checks out ok its down to three components, relay, pump, ecm
good luck
-Greg
anyways, ck nthe wiring from ecm to relay for continuity, if all wirnig checks out ok its down to three components, relay, pump, ecm
good luck
-Greg
Last edited by wietgr; 05-13-2011 at 10:35 AM.
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