1.8 Questions for the masses Options

[rick 918-S]

I was helping my old high school pal attempt to get a 1.8 running. The car is his daughters. She really wants to take it on her drivers test. May be even this week. We had some strange stuff occur.

The car was purchased at Auction. It had an engine fire due to a cracked clamp on the cold start valve. The fire consumed the center of the engine harness. Through the generosity of Betty and Clay they received a parts box at no charge. Thank you again you two!

I came into the picture when they had everything installed and we attempting to get it running.

Turned out they accidentally broke the inlet on the cold start. So I was lucky enough to source one from Jim Hoiland. Thank you Jim!

So with this install it would crank and barely run. Fuel pressure was at 40ish PSI. My friend Lowell smoke tested the intake system. All was tight.

Once we had it firing barely.. Lowell pulled the plug on the AFM and the car raced to life. Weird I know.

Pulled the plugs and notice #3-#4 were wet with Gas. #2 was dry like it never got fuel and #1 looked normal.

Lowell ordered a set of Injectors. We believe due to the process of elimination two of the injector were stuck open and one was stuck closed. Noid lighted all injectors that they are getting signal.

Any thoughts on the reason the car kept running with the AFM unplugged? Lowell thought possibly the injector that were stuck one were being siphoned allowing the engine to keep running.

[wonkipop]

i know that the engine will run on the cold start valve alone.
it did on mine when we recommissioned it.
but in my case it ran for a short time only before it switched off - from memory about 10-20 seconds at most.
(none of my injectors were working, all were stuck - tested and cleaned but just restuck again, but the cold start was working). the plug was in the afm.

not sure on control of cold start injector.
if was open and not switching off then the engine will run so long as it stays open.

[rick 918-S]

That is a thought. Possibly install a noid light with an adapter to monitor what the cold start is doing.

[jim_hoyland]

@timothy_nd28
Perhaps he will chime in. He’s posted good L-Jet info previously

[ndfrigi]

That is a thought. Possibly install a noid light with an adapter to monitor what the cold start is doing.

Sir Rick, my previous 1.8 ljet and friends 1.8 ljet only likes between 28 to 31 psi on fuel
pressure.

[ndfrigi]

deleted. not sure why double post.

[wonkipop]

That is a thought. Possibly install a noid light with an adapter to monitor what the cold start is doing.

Sir Rick, my previous 1.8 ljet and friends 1.8 ljet only likes between 28 to 31 psi on fuel
pressure.

that pressure is high at 40, but there are two tests for fuel pressure on the 1.8.
the test without the engine running and just firing the fuel pump with the afm flap is 36 lbs. there is a procedure for doing both tests, the other one for when the car is at idle. they want more fuel pressure under load and acceleration - up to 36 lbs.

timothy nd28 is the guru i reckon.

[SteveL]

On the new injectors - did he order the SMP injectors that are available from Rockauto? If so, if he also ordered the matching o-rings, you will need to use the original larger o-rings on the new injectors, as the SMP ones are too small for the bracket.
While waiting for the injectors, check for signal at the injector plugs.
If you don't already have it, I can email you the official Cap'n Krusty L-Jet troubleshooting guide.

[JeffBowlsby]

On the new injectors - did he order the SMP injectors that are available from Rockauto? If so, if he also ordered the matching o-rings, you will need to use the original larger o-rings on the new injectors, as the SMP ones are too small for the bracket.
While waiting for the injectors, check for signal at the injector plugs.
If you don't already have it, I can email you the official Cap'n Krusty L-Jet troubleshooting guide.

Can you post a link to it here in this post? I'd like a copy too please.

[SteveL]

On the new injectors - did he order the SMP injectors that are available from Rockauto? If so, if he also ordered the matching o-rings, you will need to use the original larger o-rings on the new injectors, as the SMP ones are too small for the bracket.
While waiting for the injectors, check for signal at the injector plugs.
If you don't already have it, I can email you the official Cap'n Krusty L-Jet troubleshooting guide.

Can you post a link to it here in this post? I'd like a copy too please.

I don't have it anywhere online, so no link.
Jeff - I emailed you a copy (already had your email address)

[rick 918-S]

On the new injectors - did he order the SMP injectors that are available from Rockauto? If so, if he also ordered the matching o-rings, you will need to use the original larger o-rings on the new injectors, as the SMP ones are too small for the bracket.
While waiting for the injectors, check for signal at the injector plugs.
If you don't already have it, I can email you the official Cap'n Krusty L-Jet troubleshooting guide.

Can you post a link to it here in this post? I'd like a copy too please.

I don't have it anywhere online, so no link.
Jeff - I emailed you a copy (already had your email address)

Yes they ordered from Rock Auto. I will let them know about the large seal. Sent you my email addy. Thanks all. They will get this running yet. (IMG:style_emoticons/default/driving-girl.gif)

[ClayPerrine]

Rick,
If the injectors were stuck open, that would flood the engine. Pulling the AFM plug will cause the fuel to be cut off, and then the engine will run on the remaining fuel.

You can buy injectors at FLAPS. Just get them for a 1980 Datsun/Nissan 280Zx. They are the same as the 912E injectors.


Clay

[Dave_Darling]

I remember an instance a number of years ago where a D-jet engine would run (at idle only) with the fuel pump unplugged, and die when it was plugged in.

Turns out that the CHT was unplugged, making the mixture super rich, but with just gravity-fed fuel pressure, the mixture was leaned out enough that it would actually run.

I'm saying that you could have some basic problem that is masking the symptoms, so go back and start checking the basics first.

--DD

[wonkipop]

I remember an instance a number of years ago where a D-jet engine would run (at idle only) with the fuel pump unplugged, and die when it was plugged in.

Turns out that the CHT was unplugged, making the mixture super rich, but with just gravity-fed fuel pressure, the mixture was leaned out enough that it would actually run.

I'm saying that you could have some basic problem that is masking the symptoms, so go back and start checking the basics first.

--DD

see @rick 918-S other thread about the CHT on same car?
the CHT is not plugged in. not that above is necessarily explaining the case here. but?!

great bit of information DD.

[rick 918-S]

Thanks DD! Good recall. Kind of part of what seems to be going on. I will pass on the info.

[timothy_nd28]

The airflow meter keeps the fuel pump running after the key is released from the start position. Inside the airflow meter is a set of contacts that electrically closes when the flap is deflected, which turns on part of the dual relay, which in turn, supplies power to the fuel pump.
Unplugging the connector to the airflow meter would keep part of the dual relay from turning on, thus no fuel pump action. I can see the engine running with the connector off, but only for a short time as the fuel pressure would quickly decrease. There is momentary power from the ignition switch start position going to the fuel pump, but is lost when the key returns to its run position.

So, why is the engine running with the air flow meter unplugged? Was the fuel pump wired to bypass the dual relay? It would be interesting to see a fuel pressure gauge connected to monitor the pressures while starting the car, and seeing what the pressure does as the key is released to the run position as the engine runs and the AFM connector off.

If I was working on the car, I would check the integrity of each fuel injector circuit. Start with removing the + wire on the ignition coil (this keeps you from burning up the points in the distributor while performing this following test).

Remove the ECU connector, and with the key to the run position, check for voltage on pins 14,15,32,33 (ECU connector) to battery ground. You should be seeing 12 volts. If you do, that proves that the ignition key is turning on the dual relay, the dual relay is passing voltage to the resistor pack and that fuel injector coil has continuity.