No Start driving me crazy!

Dan Owens · 07-30-2020, 07:39 AM

I'm having a very confusing no start situation on my 1984 3.2 Targa.

The car was in storage for about 2 years. Prior to storage I drove the car in with no problems. I disconnected the battery and drained the gas.

When I went to take the car out of storage it would'nt start. It turned over no problem but just not fire up. I went thru the normal checklist of fire, air, gas and grounds. It had spark, has air and fuel seemed to be lacking. I checked the tank and fuel pump and there was debris in the tank and clogged the fuel line and pump. I pulled the tank and cleaned it out, replaced the pump and strainer and fueled it up. Had fire and air and fuel supply thru the fuel rails with decent flow and volume but still not start. I tested the ECU and DME and they are ok. I had questionable test results on the speed and reference sensors and replaced those. I tested the CHT sensor and it's good, (newer 2 wire version) After replacing the 2 sensors, it cranks has spark, air and fuel supply but still no start. I checked the ICV valve is running fine, I checked the injectors and have solid test lamp at key on and noid light confirms they are getting signal to pulse.

I'm getting no fuel smell from the exhaust when I crank it. If I spray starter fuel in the air intake snorkle and crank the engine and it starts briefly until the fluid evaporates and then dies so it appears it's getting no fuel thru the injectors. I also used my phone to video the backside to make sure of loose vacuum hoses and see nothing amiss, all the hoses were replaced when the engine was rebuilt.

I don't have a fuel pressure test gauge but am on the way out to pick one up to test my pressures to make sure of the pressure. after I run the pressure test I'm pulling the injectors to check and test flow thru them just because I've gone this far. I'm running out of things to check so I'm looking for hints or ideas if it's not a fuel pressure issue from the regulator or damper being bad. I think the fact that it starts with starter fluid and then dies confirms it's lack of fuel but still I'm slightly stumped. Anyone have any suggestions?????

proporsche · proporsche's Garage

you have done everything correctly..and good job...yes pull out one fuel rails and see if the injector are spraying.....just be careful on the left side where the power is at the fuse box..dip the injectors into little bottles..

Ivan

btw you have fuel at the fuel filter-you can hear the pump?Again be careful at the left side of your engine...with the fuel

mysocal911 · 07-30-2020, 08:01 AM

Quote:

Originally Posted by Dan Owens

I'm getting no fuel smell from the exhaust when I crank it. If I spray starter fuel in the air intake snorkle and crank the engine and it starts briefly until the fluid evaporates and then dies so it appears it's getting no fuel thru the injectors. I think the fact that it starts with starter fluid and then dies confirms it's lack of fuel but still I'm slightly stumped. Anyone have any suggestions?????

Very likely that the injectors are clogged, happens when engine isn't run for long periods of time.
They need to be pulsed externally with the DME ECM disconnected.

Dan Owens · 07-30-2020, 09:07 AM

Ivan, Yes I have fuel flow thru the filter and thru the injector fuel rails. I flushed out all the lines as part of the fuel pump replacement. I have good flow rate and volume just not sure of the actual pressure. I just got back from picking up the pressure test kit so pressure verification is next on the list. Then pulling the injectors either way to check ad clean them.

Dan Owens · 07-30-2020, 09:08 AM

Dave,

How do you pulse them without using the ECU and DME? Battery?

Dan O

proporsche · proporsche's Garage

so you have fuel to the rails but do not know about the spray correct?

As Dave said possibly clogged but...all of them seems strange....so let wait what you find...

GH85Carrera · GH85Carrera's Garage

Trey getting a NOID test set for the injectors. It will test if they are getting the pulses.

Dan Owens · 07-30-2020, 10:18 AM

Quote:

Originally Posted by proporsche

so you have fuel to the rails but do not know about the spray correct?

As Dave said possibly clogged but...all of them seems strange....so let wait what you find...

Yes that's what's confused me as I can see a couple clogged but not all of them . Strange

Dan Owens · 07-30-2020, 10:20 AM

Quote:

Originally Posted by GH85Carrera

Trey getting a NOID test set for the injectors. It will test if they are getting the pulses.

AS I mentioned in the original write up I have both a solid 12 v signal with ignition on. I also have pulse when I use the Noid lights on all injectors just apparently no fuel thru the injectors.

proporsche · proporsche's Garage

lets see...

Glen he did ..look;-)"I checked the injectors and have solid test lamp at key on and noid light confirms they are getting signal to pulse."

Dan Owens · 07-30-2020, 10:29 AM

OK, next update. I just pulled the fuel pressure test off the injector rails. I pulled it twice just to confirm.

First test I ran the pump via jumper at the fuse box. I got 37 lbs of pressure.

Second test was via cranking the engine and letting the DME drive the pump. I got a solid 37 lbs of pressure on this second test as well.

I show the pressure should be 40 lbs but I think being as close as I am I'm ok???? anyone think I need those last 2.5 lbs of pressure???? I don't know the cracking pressure of the injectors. Anybody know that detail? I can't find it anywhere yet.

Next I'm pulling the rails and the injectors as I have no other idea of where to go. It clearly does not seem to be getting spray thru the injectors. It may wait until the AM for that as it's scorching hot outside right now.

proporsche · proporsche's Garage

how is you return fuel line, is it pinched somewhere? double check the impulse the injectors again..

The fuel system press should 2,5 bar when running about 2 bar

Ivan

GH85Carrera · GH85Carrera's Garage

Quote:

Originally Posted by Dan Owens

AS I mentioned in the original write up I have both a solid 12 v signal with ignition on. I also have pulse when I use the Noid lights on all injectors just apparently no fuel thru the injectors.

Whoops, I missed that in the first read through.

There must be a fuel blockage somewhere if it runs with starter fluid.

proporsche · proporsche's Garage

here..

Dan Owens · 07-30-2020, 11:43 AM

Quote:

Originally Posted by GH85Carrera

Whoops, I missed that in the first read through.

There must be a fuel blockage somewhere if it runs with starter fluid.

Glen, I would agree and based on what I've tested and written up I'm already searching the issue. I have fuel flow, volume and correct pressure to the rails and injectors. I have spark to the plugs, I have pulse signal to the injector but it appears no flow thru the injectors. I have no issue that I can see for a clogged line as I've got fuel all the way to the injectors so the injectors are next on the list. If it were some other issue it would not start using starter fluid replacing the fuel from the injectors, at least in my way of thinking based on what I've done in troubleshooting. Just very odd all the injectors would clog at the same time but I guess I'll know soon

Dan Owens · 07-30-2020, 11:45 AM

Quote:

Originally Posted by proporsche

here..

Thanks for that info

Dan Owens · 07-30-2020, 11:47 AM

Quote:

Originally Posted by proporsche

how is you return fuel line, is it pinched somewhere? double check the impulse the injectors again..

The fuel system press should 2,5 bar when running about 2 bar

Ivan

Ivan, Fuel return is clear and working. My pressure is in spec so I've ruled that issue out. It's gotta be the injectors clogged, just odd all would clog completely at the same time.

proporsche · proporsche's Garage

ok let`s hope so...keep us posted

Ivan

darrin · 07-30-2020, 12:03 PM

Dan: Probably a BTDT for you, but just in case -- have you confirmed that your DME Relay is working properly -- it is actually two separate relays, one triggers / powers the DME computer itself and the other triggers/powers the fuel pump -- a failed DME relay would not allow the fuel pump to run properly/consistently. If you don't have a spare, you can remove the rely and jumper its connectors to force the fuel pump to run while the ignition/starter are on -- if you haven't already ruled this out

mysocal911 · 07-30-2020, 01:56 PM

Quote:

Originally Posted by Dan Owens

It's gotta be the injectors clogged, just odd all would clog completely at the same time.

It happens!!!

To pulse the injectors without having the DME ECM connected:

1. Turn key on.
2. Verify that injectors have 12V on them.
3. Use a jumper wire to ground either pin 14 or 15 on the DME ECM connector momentarily multiple times.
This will need to be done for typically for 3-5 minutes.