 Brain Shot?, I know mine is but what about the FI |
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| tdgray |
 Aug 7 2003, 06:37 AM
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#1
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Thank God Nemo is not here to see this  Group: Members Posts: 9,705 Joined: 5-August 03 From: Akron, OH Member No.: 984 Region Association: None  |
Is there a definitive way to tell if the Fuel Injection Computer is shot. I have downloaded the usual technical stuff and can't seem to make any sense of it yet! Anybody that can give me a play by play instructions for checking it? I have narrowed my problems down to relays and / or bad computer and / or bad wiring. Fuel pump seems to be OK. Any advise guys, whats the next step? (IMG:style_emoticons/default/confused24.gif)
Thanks, Todd 1960 MGA 1973 914 1.7L |
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| seanery |
Aug 7 2003, 08:06 AM
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#2
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waiting to rebuild whitey! Group: Retired Admin Posts: 15,854 Joined: 7-January 03 From: Indy Member No.: 100 Region Association: None |
We thought my car (74 2.0 at the time) had a bad computer, just swap it out is the easiest way.
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| Bleyseng |
Aug 7 2003, 08:07 AM
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#3
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Aircooled Baby! Group: Members Posts: 13,035 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
First to go are the relays, then the wiring, last of all is the ECU. Always check the relays first.
What are the problems you are having? Geoff |
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| tdgray |
Aug 7 2003, 09:48 AM
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#4
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Thank God Nemo is not here to see this Group: Members Posts: 9,705 Joined: 5-August 03 From: Akron, OH Member No.: 984 Region Association: None |
Thanks All for replys. Here it is in a nut-shell. No power to the fuel pump wiring. When I jump a hot wire to the Fuel pump it works so must either relay or wiring. Tried swapping another relay off the board (not the main power one) into the fuel relay socket, Nothing. Ok so I tried giving the fuel pump power via jumper with the relays attached figuring I would see if I could just get it cough or something, Nothing! Engine does run if I squirt some gas directly into the throttle body so that is not a problem. I guess I'm at a loss and hate to just keep trying stupid things. I did order a new relay should be here in next few days. What else should I be checking in the mean time? This FI is all greek to me I'd rather sync my MG's carbs 20 times than troubleshoot this (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif)
Thanks Guys, Todd |
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| Alfred |
Aug 7 2003, 10:00 AM
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#5
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Unregistered |
You can rent a fuel injection tester from Pelican http://www.pelicanparts.com/support/ecu_testers.htm .
Alfred |
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| Bleyseng |
Aug 7 2003, 10:28 AM
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#6
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Aircooled Baby! Group: Members Posts: 13,035 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
Look at the relay board for problems. Take it out and flip it over and look at the circuits. Since the heater booster fan and the fuel pump are on the same circuit you can burn out that circuit line with a bad fan.
Try the jumper between the fuel pump pins (refer to the PelicanPart article) and if that doesnt to the fuel pump on, take the relay board out. Geoff |
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| TheCabinetmaker |
Aug 7 2003, 11:47 AM
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#7
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I drive my car everyday Group: Members Posts: 8,301 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
don't forget to check the fuse on the relay board.
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| Dave_Darling |
Aug 7 2003, 03:49 PM
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#8
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914 Idiot Group: Members Posts: 14,991 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California 
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Unplug the four-pin connector on the relay board. With the key on, check for power at the right-front pin of that connector. Hook a ground wire up to the left-front pin, and listen for the fuel pump. The ECU runs the pump by grounding the wire that goes to that pin.
You can also plug the four-pin connector back in, and poke the probe of your multimeter in the back of the connector where the left-front pin is. Check that for continuity to ground when the starter is being cranked. --DD |
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| JeffBowlsby |
Aug 7 2003, 05:07 PM
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#9
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914 Wiring Harnesses Group: Members Posts: 8,522 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None
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QUOTE When I jump a hot wire to the Fuel pump it works so must either relay or wiring. Smells like the relay board to me, or a loose connection somewhere. Patience Grasshoppa...the FI system is not that hard if you are methodical, as you already have shown us... |
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