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Discussion Starter #1
Hey All,

Picked up a 1986 Spider a couple of weeks ago, 42k original miles. Paint is battered from sitting in the Texas sun since 1995, everything else seems to be in decent shape, although covered with dust.

The car was sitting since 1995. The niece of the owner (deceased) and a friend had it shipped out here to California and attempted to get it going, then eventually gave up. I found it on CL and am now having my own frustrations.

I've replaced a bunch of fuel lines and have gone through the Greg Gordon Spider LJet troubleshooting guide. Everything seems to be in order, sensors all measure correctly, etc etc. VVT doesn't kick in, but I can deal with that later. For now, the only thing I can't figure out is the injectors. They all measure fine, but they're not getting any signal. Car gets spark, but obviously no fuel.

I was also having fuel delivery problems, went through 3-4 used fuel pumps, just ordered a couple of new proper Bosch pumps, but in the mean time what could be causing the injectors to not fire?

I hooked up the Autoforce tester, and with the right combination of settings I was able to get the injector light on the Autoforce to flash during cranking, but by that point I'd gone through used fuel pump #4 and was ready to call it a day.

Right now here's what I've done:

1) Gone through the entire Greg Gordon troubleshooting guide. All sensors, crank triggers, AFM, etc measure as they should.
2) Found one air leak, fixed it.
3) Installed a brand spanking new 1 gallon fuel cell, and replaced most of the fuel lines. While the injectors might be gummed up with stale fuel, everything from the tank to the fuel rail is essentially new.
4) New fuel filter.
5) Replaced the EFI ECU with a known good one.
6) Spark is good.

Without the Autoforce, I don't get any kind of signal at the injectors. With the Autoforce, I can force some settings to get the injector light to trigger. I'm guessing that if I put in a new fuel pump, at this point it should start. But not without the Autoforce.

Any suggestions?

Thanks All,

bs
 

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obviously you need to get your new pumps organised first

then, even if the injectors are not firing, you should at least get a 3 or 4 second run from the engine, as the cold start injector would fire regardless (it is independant of the ecus)...of course check that the csi is even working first....take it out and aim it into a jar and crank the engine...if sitting for the last 25 years with stale fuel I really think your injectors and the csi are going to need servicing...even if they get an electrical pulse (the 4 injectors are pulled to ground to fire and the CSI is grounded by the TTS), they might not be spraying (well)

you say injectors 'all measure fine'....meaning what exactly?
have you got voltage both sides of the injectors? what voltage do you get each side?

check and clean the ecu grounds on the passenger side of the head (and any under the AAV, if those are still there, sometimes they have been moved down to the head grounding point)

try removing the thinner white wire from the coil negative, the tach wire, then test for cranking signal at injectors.
 

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As we all know, carbs gum up because, if a constant fuel source is available, there is continued, slow evaporation from the float bowls which leaves behind less volatile gasoline products.

That being said, I wonder how an injector can suffer from anything besides stale fuel sitting in the innards? Following a few crank cycles, it would seem they would be self-cleaning, other than the stale fuel part.

How do the two flywheel sensors play into injector function, if at all? Presence of spark would seem to rule them out as a problem.
 

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Discussion Starter #4
obviously you need to get your new pumps organised first

then, even if the injectors are not firing, you should at least get a 3 or 4 second run from the engine, as the cold start injector would fire regardless (it is independant of the ecus)...of course check that the csi is even working first....take it out and aim it into a jar and crank the engine...if sitting for the last 25 years with stale fuel I really think your injectors and the csi are going to need servicing...even if they get an electrical pulse (the 4 injectors are pulled to ground to fire and the CSI is grounded by the TTS), they might not be spraying (well)

you say injectors 'all measure fine'....meaning what exactly?
have you got voltage both sides of the injectors? what voltage do you get each side?

check and clean the ecu grounds on the passenger side of the head (and any under the AAV, if those are still there, sometimes they have been moved down to the head grounding point)

try removing the thinner white wire from the coil negative, the tach wire, then test for cranking signal at injectors.
Thanks. I removed and cleaned all grounds. Curiously, there is one white wire already removed from the coil, I should have snapped a pic. I tried it on and off, but I'm not sure what that wire is for - perhaps the tach? I know the PO was also futzing around with troubleshooting.

Wrt the injectors measuring fine, the impedance reads 2.2 - 2.5 ohms for each of them. They're low impedance injectors, 2-3 ohms is what they should read.

New pumps should be here later this week. I'll report back when I've got one installed.

Thanks!

bs
 

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Discussion Starter #5
As we all know, carbs gum up because, if a constant fuel source is available, there is continued, slow evaporation from the float bowls which leaves behind less volatile gasoline products.

That being said, I wonder how an injector can suffer from anything besides stale fuel sitting in the innards? Following a few crank cycles, it would seem they would be self-cleaning, other than the stale fuel part.

How do the two flywheel sensors play into injector function, if at all? Presence of spark would seem to rule them out as a problem.
Agreed on the fresh fuel. I also added what is a high concentration of a degummer, and I'm hoping that once fuel starts circulating that will help with the injectors. Lesson learned - just because you can hear a fuel pump running doesn't mean you have fuel or pressure at the rail. Always check for pressure at the rail! After I replaced the fuel pump and a lot of the plumbing I wasted a fair amount of time on other things, assuming I must have pressure at the rail. I didn't.

As for the flywheel sensors, I know one is for the ignition. Both sensors measure fine (~1250 ohms, I think spec says 1200-1400), and to the best of my knowledge the engine, flywheel, and transmission have never been out of the car, so I don't think there's a chance that they've been assembled improperly.

Fuel pumps coming later this week, I'll install and hopefully make some progress this weekend.

Thanks!

bs
 

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Discussion Starter #6
Installed brand spanking new fuel pump today. Now I think the battery needs some charging due to all the cranking last week. I did crank it a little bit this AM and still can't get so much as a sputter out of it.

Attached is a photo of the wiring at the coil. The white/black wire looks like it should go on the negative side of the coil, I'm guessing somebody took it off as part of troubleshooting at some point. Is that correct?

I'll play some more later, wanted to get this picture up get the coil wiring sorted properly.

Thanks,

bs
CeRy%AMsRHSBRtvj9gIsfQ.jpg
 

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Discussion Starter #7
Quick update.

At this point I've narrowed it down to clogged injectors (probably the cold start injector too). Installed the new fuel pump, and also a fuel pressure gauge inline with the fuel rail. I've got spark and 35 psi at the rail.

Connected one of the injector leads to a spare GTV6 fuel rail we had lying around and that injector is firing just fine. So I'm confident in the wiring and signal to the injectors.

That kind of points to the injectors themselves. They read 2-3 ohms each, but they're not firing, which I assume is simply because they're clogged big time. I'm looking for a fuel rail to slap in there (emailed APE!), if they don't have something I'll R&R this fuel rail and let the injectors spend some time in the ultrasonic cleaner.

bs
 

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that white/black wire at the coil should be connected back to coil negative...it goes to drive relay.
And what is that red wire doing on your coil positive? where does it go to, what is it for?
 

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Discussion Starter #10
that white/black wire at the coil should be connected back to coil negative...it goes to drive relay.
And what is that red wire doing on your coil positive? where does it go to, what is it for?
That red wire is part of a hokey 2 connector jumper. Look closely, it's connected to a grey wire which looks like it's spliced to a brown wire. Also in that connector is a wire going to the other side of the coil, coming from the same harness, with the same level of splicing and hackery involved.

Thanks for confirming my suspicions on the white/black wire, and explaining where it goes to. I'll put it back, and probably put together a proper set of ring terminals for the two hacked up wires at the same time.

bs
 

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Discussion Starter #11
OKINJECTORS
Thanks! I've got an ultrasonic cleaner, and have done this in the past. I was hoping to get it running without taking too much more apart, if I have to go that route I can clean the injectors. I've never done the crimping part of rebuilding the fuel rail, perhaps it's time to learn that..

Thanks,

bs
 

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yeah but why is that hokey wire there!
On that side belong 2 green/blacks.....and they look like they are there already.

strange mess of wires
 

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Discussion Starter #13
yeah but why is that hokey wire there!
On that side belong 2 green/blacks.....and they look like they are there already.

strange mess of wires
Good question. Next time I'm out there I'll trace them backwards a bit.

bs
 

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OK Injectors is no longer doing injector service. I've used Cruizin Performance and been pleased with their work.

I've never done the crimping part of rebuilding the fuel rail, perhaps it's time to learn that..
Crimping? There is no crimping involved. With the correct 7.5mm ID fuel hoses they just push onto the fuel rail & injectors. (1/4" is too small, 5/16" is too large) The cup shaped washers (#3) are there to keep the ends of the hoses from ballooning open. Note that to remove the old hoses the shop manual advises the use of a soldering iron to melt through the hose. This avoids the risk of nicking the hose barbs - which can be the source of a leak - if a knife were used.

1637507
 

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Are you sure that the injectors are getting a constant signal during cranking? Are you using a NOID light? Great tool, inexpensive too. On rare occasions I have seen the inlet side of the injectors clog with fine grit. Maybe because of a failed fuel filter? Unfortunately, the only to check for this is to remove them from the fuel rail which is a PITA. If you go that route, replace the nozzle o'ring seals.
 
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