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Mburkey 02-29-2012 02:18 PM

94 YJ turns over but won't crank
I have a 1994 Jeep YJ that suddenly won't crank.:nonono: A few years ago it was converted from a 4 cyl to a Chevy 350 (is not fuel injected). There is power from battery to relay but something is not giving signal from relay to distributor. Of the 5 prongs on the fuel pump relay, if I wire it to the middle prong it cranks but won't turn off. If I have it wired to the prong it should be, it will turn over but won't crank. I've replaced the distributor cap and ignition coil even though the coil tested good. When I have it wired to the fuel pump relay as it should be, I go from 12v to that normal? Is there a safety switch for the fuel pump (it's a manual fuel pump) that may have been tripped? If so, where is it located? My teenage son was backing it into the driveway and it died and would no longer crank. The rotor does turn. Any ideas will be appreciated!
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Garyk 03-01-2012 02:56 PM

So it turns over but does not start??I take it the original computer has been removed. Do you have a different ECM for the chev engine or is it just wired in from the fuse box ? If its a manual fuel pump there is nothing there that would affect the start of the engine unless it quit pumping and that can be checked at the carb. Have you checked for spark at the plugs?

Timberwolf 03-01-2012 04:50 PM

by manual fuel pump, do you mean mechanical? that shouldn't even need a relay

if it's an electric pump, try different relay, it shouldn't drop to 8v

Mburkey 03-11-2012 07:59 PM

Thanks. I'm not a mechanic by no means at all. this is the first i've even tried to work on a car. have replaced the alternator, cleaned the battery ground, replaced the battery is now cranking but the battery won't charge. I can jump it off and drive it around but after turning it off, the battery is totally dead and that's after only 10 minutes of driving. Alternator bench tested good but had it tested inside Jeep and tested at 10.4 so that's why I replaced the alternator.

chrisnarron 03-11-2012 08:03 PM

Have you tested the battery?

Mburkey 03-11-2012 08:05 PM

battery tested good at parts store

Mburkey 03-11-2012 08:15 PM


Mburkey 03-11-2012 08:21 PM

The relay is not working on crank. Temporarily we wired up a switch inside Jeep so it's always on (hot wire), so we have to use the switch to turn it off. With that switch it cranks but now the battery won't hold a charge or isn't being charged...I'm lost.

Mburkey 03-11-2012 09:39 PM

I've read in other posts about a PCM. Where is this located and remember this is has a 350 Chevy. I'm a frustrated mom trying to help my teen son fix his very cool Jeep.

Master4th 03-12-2012 12:02 AM

I did away with those relays, computer, emission equipement when I did my 350 swap. I remember reading in another post there is a resister that drops the voltage on the distributer wire.

Here is what I did, Find a wire that is 12v with the key in the Run Position. Run that wire to your distributor or to the wire at the relay and bypass the relay. If your running a mechanical fuel pump, [The kind plugged into the engine] then you dont need the relay.

The reason it wont shut off when you wire it to the other pillar is becuase that wire is a constant 12v's you need a 12v source that turns off with the key so that when you turn the key off it stops power to the distributer.

Remember you need a wire that is 12v only in the run position. If its hot in the acc position thats a no go as well. Acc is for when you want to sit there and listen to the radio without the engine running.

Mburkey 03-12-2012 08:02 AM

Okay. The problem is I'm not sure which 12v wire is hot only on crank and run. How would I find it? For now, I have the wire bypassing the relay and going to my battery terminal and then to my distributor. So it's possible I don't have an ECM? Where would I look to see if I have an ECM so I can try to rule that out as my charging problem? Thank you.

Mburkey 03-12-2012 08:34 AM

'94 YJ
Please help me restore their smiles :)

Mburkey 03-13-2012 07:42 PM

Something is either draining the battery or the battery isn't receiving a charge. I'm going in circles. New alt, wires test good, put in new battery and it drained too and wouldn't recharge. Any new ideas? Starter? Selenoid?

Master4th 03-13-2012 08:08 PM

See my post in your other thread.

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