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Discussion Starter #1
I have acquired a 1986 Spider Graduate. The car has been in storage for 4 years. The car was driven into the storage location with minimal problems (tail-lights / head-lights didn't work). After changing the oil/anti-freeze/spark plugs and draining the gas tank, I put in new gas and a new battery and tried to start the car. The car was just turning over. I put some starting fluid in and the car would run until the ether ran out. Upon reading some threads on this board, I discovered that I was not getting fuel to the fuel rail @ the injectors. I proceeded to replace both fuel pumps, replaced fuel filter and all of the rubber fuel lines. I tried to start the vehicle again, same result, car would run only as long as the ether lasted. I took the fuel line off of the fuel rail and took a bath in gasoline. So the fuel pumps are working to get the gas to the injectors.

Question 1: Is there any way possible that all 4 injectors could be clogged?

Question 2: Is there any way to check the ECU to see if it is faulty?

Question 3: Can the relays be tested?

Question 4: Is there something else that I need to be looking for or testing?

Any feedback would be greatly appreciated.
 

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#1 If the car was not parked with 4 years storage in mind it seems quite likely the injectors could be clogged. I resurected an '84 Spider that had sat for 1-2 years unused. Before I started it up (after an engine rebuild) I sent the injectors to Cruzin Performance for cleaning and testing. (There are other places that offer similar service)

#2 Not easily. Generally, one tests everything else until the only possible fault left is a failed ECU. However, the L-jet ECU is considered fairly robust. It is much more likely another component has failed - a sensor or relay for example.

#3 They are basically just electrical switches so if one knows the input and output expected then, yes one can test them. Have you tried tapping them with the handle of a screwdriver? Just hold the screwdriver end between your finger & thumb and boink the handle onto the relay. Sometimes that will wake up a reluctant relay!

#4 See the link in my signature block for a web page about L-jet diagnosis. There are two relays next to the FI ECU (you car has two ECU's, BTW - one for FI and one for ignition). The drive relay gets a signal from the coil so it knows the engine is running (or cranking). And the main relay sends power to the injectors. Injector control is then done by the FI ECU as it controls the ground path for the injectors.

The fact it'll run for a short time on starting fluid seems to indicate that the ignition system is functioning. But I'd suggest verifying that. It is more typical for the ignition system to have a fault and then, without the proper input signal from the coil to the drive relay (and thence to the main relay) the injectors don't squirt.
 

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Discussion Starter #3
One more quick question

Thanks for the info. I printed out the L-Jet link that you referred me to. I will be trying alot of those tips.

Just one more quick question, is there any way to determine that the fuel injector is getting the signal to fire? Can I unhook the connector and hook up a simple 12V light to the harness and turn the engine over to see if it is getting the signal to fire? I read most of that link and it states specifically not to use an ohm meter to test for fear of shorting out ECU, will hooking up a 12V light cause the same effect?

Any input would be greatly appreciated.
 

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You can use a mechanics stethescope or a bit of vaccum hose to see if the injector is firing without disconnecting the electrical connection.

It'll give a very distinct 'tick' noise as the needle hits the end of travel every time it activates and deactivates. (sounds simular to a relay clicking on)
 

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I've read about but not used an item called a "noid" light for checking the FI signal. It gets plugged in to the harness connector at the injector and is then supposed to flash as the ECU sends the signal to squirt fuel.

To listen for the injector clicking I just use a long screwdriver. Place the screwdriver end against the injector and put your ear near the handle end. You can definately hear them clicking if the internal coil makes the needle move.

Neither the noid light or a listening device tells you if they are actually squirting fuel though (if they are clogged) ...

A relatively easy test would be to pull out the CSI and see if it will squirt. If it does then the fuel pressure is likely OK. That dosen't tell you if the main injectors are squirting however. A more difficult but definitive test is to remove the fuel rail and injectors and then crank the motor with the injectors out. If you can see them squirting then you know they are functioning. If not then you have to figure out if it is due to clogged injectors or lack of signal.

I have experienced loose contacts inside the harness connectors. If you look inside the connector you should see two female spade terminals. Pull on the wires leading into the connector and see if they pull backwards (they shouldn't). If they do they may not be making contact when you plug the connector onto the injectors. But it'd seem unlikely that all four would fail like that...
 

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If no injector but the CSI fires, it might be a case of a failed relay back by the ECU. Either the tachy relay not sending signal, (may or may not cause pumps to not run depending on several variables), or the other one just flat out died. (broken ground wire on either isn't out of the question either)
 

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Discussion Starter #7
Still No Luck

I have been following your tips and the L-Jet link but to no avail. I have checked and cleaned all of the grounds. I have checked the flywheel sensors both okay. I tapped on the two relays but still not fuel in the cylinders from the injectors. Like I said in my earlier post, I am getting fuel up to the fuel rail, but still no fuel from the injectors. I cannot hear the injectors ticking. I checked one injector, the rear of the motor (easiest to get to) and the coil in the injector is fine according to the Ohm meter.

As far as me not being able to hear the injectors ticking, could it be that they are gummed up and unable to move, or is it more likely I am not getting the signal to the injectors to fire?

I personally think that it is highly unlikely that all of the injectors are stuck closed, but as far as I know, I am running out of options to check. Should I replace all of the injectors? I can get new injectors from Autozone for $45 each, cheaper than having them cleaned. But I don't want to make the investment unless I have no other options.

If there are any more tips out there please share. Any help would be greatly appreciated.
 

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Cruzin Performance will clean (ultrasonic + soak in solvent), install new inlet screen & test for $16/injector. Turn around time is quick - about a week.

Are you certain the ignition system is functioning? You said it'll run on ether but have you confirmed it is actually making spark? No spark = no signal to drive relay = no fuel injection.
 

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Discussion Starter #9
Success!!

First off, I would like to thank everyone for their tips on getting this car running. After deciding to remove the fuel injectors to replace them, I removed the injector in the far rear of the vehicle and had someone crank the motor over just to see if it was spraying. It did nothing, but before I removed the injector, I depressed the little needle at the end of the injector, and gasoline sprayed across my garage. I depressed it again and it start misting the gasoline. I had the engine turned over again and the injector started spraying the gasoline. I did a lot of work to get this vehicle running and all that I needed to do was clean the injectors. Who knew it could be such a simple thing. Once again thanks to everyone.

Now that it is running, I found some vacuum lines that need replacing. Does anyone have any tips for replacing the runners that go between the intake plenum and the intake? I tried to remove yesterday, but I could not get enough clearance to get the old ones off.

Any help would be greatly appreciated.
 

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There's a bracket that holds the intake plenum in place which attaches to the passenger side motor mount. You may be able to loosen the bottom of it a bit, then unbolt it from the plenum, and swing it out of the way. If I remember correctly, the fuel rail is also attached to this bracket, so you'll have to unbolt that as well. You will also most likely at least need to unbolt the oil vapor canister and move it out of the way so you have clearance for the plenum.

I just tore my engine down and pulled it on my 82 spider. By the time I got to that bracket, I had almost everything out of the way, so hopefully this is doable without pulling too much else off.

Let me know if this helps or not. :)
 

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If you are going through the trouble to R/R the intake plenum, consider replacing the right side motor mount at the same time. That mount is difficult to access with everything in place. With the plenum off, it'd only be a little more work to R/R the motor mount.
 

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I would agree... and also add that if your starter is suspect and/or weak, I'd do it then too... it's quite a PITA to get to with all of that in place, unless somebody knows a trick I'm not privvy to. :)

One other thing to look it if you end up removing the plenum is changing out the oil pressure sender on the passenger side of the block. It was ~$6 if i remember correctly from Centerline. This is the sender that runs the "oil idiot light" as I like to call it. :D

From what I understand they don't go out too often, but $6 insurance is pretty cheap, IMHO. :)
 

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I had the same problem as you did. After all the checks it turned out that the fuel pump inside the tank was not working well (at times it would work fine).
I used cruzin performance recently and the injector are so much better now. The guy at cruzin performance is very very reliable, but i would also look into the fuel pump inside the tank.... it not uncommon for them to go bad especially after our old tanks collect dirt.....

My input.
 
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