'87 240 Spark, No fuel

Denied72

Heyo, i'm at my wits end and need a bit of help

Just put my engine in with a new ignition harness and for the life of me I can't get it to get fuel to the engine. Pump doesn't run with the key but runs when the fuses are jumped, injectors are not firing at all. I've heard a underhood 25A fuse should be there, can't seem to find it but I've got this janky bush mechanic fuse thing in place of it I believe

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This car runs LH2.2 with a Chrysler ignition if that helps.

Cheers,

Michael

TL_V70

That's a resettable Circuit breaker that's removed from its housing ( shouldn't really come apart.

When it draws current over its preset amperage rating the metal strip heats up and opens. Acting like a fuse then when it cools down it resets and closes again.

Denied72

TL_V70 Yeah I pulled it out to check what the hell it was, put it back and shes sweet I think. Seems the fuse holder is mounted there on other models though?

TL_V70

It should have an Amperage numer on the stamped into the metal case. If not find out what side the factory fuse size was and just get a new circuit breaker of that size..

I am no expert on any 240s but I would the original fuse holder probably melted or failed and was replaced with a auto reset circuit breaker at some stage. The black on the studs is just heat shrink so nothing falls on the posts and shorts out.

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Denied72

TL_V70 Yeah thanks, so this is in-place of the fuse and as long as it hasn't failed it should be doing the job, so my problem might be elsewhere.

TL_V70

And the fact it's covered in rust is a good idea to replace it.

TL_V70

Jay car and Super cheap ect sell them there not odd or rare just make sure ypu get the correct Amperage rating for that circuit eg what factory fuse was.

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TL_V70

Yes in place of the factory fuse. They should come apart easy tho. I would replace it as off wall the corrosion and if it was easy to come apart it wasn't sealed and letting water / elements inside.

It works like a set of points in a distributer if their dirty they won't conduct. If it didn't start then you messed with that circuit breaker and it started I would suggest it's your problem.

There dirt cheap to replace. Jaycar was like $12

TL_V70

Shouldn't come apart easy sorry.

TL_V70

There just an auto resetting fuses. So you don't have to carry fuses with you.

ramrod

Is there any injector pulse?

Denied72

ramrod I don't believe so. Injectors fire on the bench when given 12v. Haven't been able to properly test it with the multi yet.

ramrod

This needs to be verified.

Pull out the rail again, leave the injectors attached. Ensure the ground wiring is still bolted down and crank engine to see if any fuel injecting.

That or use a noid lamp to test for pulse

Denied72

ramrod Ah yeah, I've had them out, grounded and cranked the engine while jumping the fuel pump and nothings come out of them. I can go back over after and get fuel out if I give them 12v from an external battery.

So currently, I have spark, timing is correct but fuel pump and injectors are not running when on/cranking.

ramrod

I did not realise the fuel pumps weren’t running.

Have you checked the fuel pump relay?

That’s the first thing you would check when diagnosing a no start.

Denied72

ramrod I would think that the injectors would be firing without the pump relay, but no I haven't gone and looked at it yet. Will when I get time next but I'm not sure how related it is to the injector problem as i've heard its possible to run the car with the fuses jumped if the relay is dead.

ramrod

Yes, so long as the ECU senses the engine is rotating, it will ground the injectors and they will open if fuel pressure is present.

The relay not working can prevent this.

You mentioned you replaced the ignition wiring harness. What about the rest of the injection harness? No injection could quite possibly be the result of shorted wiring. Very very very common on a 1987 240.

Have you examined the engine wiring?

Denied72

ramrod I've replaced the engine wiring harness with new, including the ignition harness. the fuel harness looks to be in good condition up behind the firewall too. I believe I have everything plugged in in the right places.

Didn't realise the fuel relay was played a part in the injection circuit. I thought it would've just had a sender.

ramrod

That’s great that you’ve replaced the harness.

I would double check all individual wires are seated completely.

Triple check the orange and black wires are connected underneath the inlet manifold. As well as the ground wires for the injectors.

You can hold the terminals closed inside the fuel pump relay, pumps will run full time.

I would then check injector pulse. And permanently connect the fuel injection fuse wiring by the battery.

If none found, and all wiring is verified connected, ECU could be faulty

Denied72

ramrod Where does the orange wire go to? From memory I have one female single blade connector on the harness poking out near the dizzy with an orange wire, doesn't seem to be for anything, I assumed it was for the coolant temp sender but it could be my problem