I just put a stock '74 2.0 motor in my car with the stock D-Jet. I had the motor running in the car I took it out of.

Here is my issue. Upon my initial startup, it was running on #3 and 4, and intermitently on #2. #1 did not fire at all. I confirmed spark at all 4 cylinders. I pulled out the injectors and fired them into glass jars. No fuel from #1 and very little from #2. I tested #3 and 4 for a baseline and got fuel.

Then I swapped injectors 1 and 2 for 3 and 4 and started it up again. This time, #1 and 4 were firing and #3 wasn't at all. #2 appeared to be intermitent again. While it was running, I'd pull the plug wire and if the rpms dropped significantly, I deemed that cylinder to be firing. I also tried it with the connectors to the injectors. Same results. On #2, the rpms dropped very little but still noticable.

While the motor was running, I confirmed that a signal was going to the non-firing cylinders with a noid light. All 4 of these injectors were sent to Cruzin Performance for cleaning and testing.

Any thoughts?

Maybe some crud plugged the injectors. You may also have an intermittent electrical problem. Make sure all connectors are clean and plugged in fully. re-check the grounds.

Why would an injector that ran fine on one side not run on the other side? If it was an intermitent electrical problem, wouldn't the noid light also be intermitent?

Maybe the problem wasn't present during your noid test. Try it again.

Chris,
Go get four glass jars.
Pull all four injectors and rest them in the jars, all hooked up.
I use baby food jars.

Remove the high voltage coil wire.
Turn over the motor for about 30 seconds.
Measure the fuel in each jar (by eye is fine)

Rich

I hear 2 problems

1. shitty injector ground at teh block ground junction
2 dirty injector

solution:
1. clean your ground spades. the female may have corrosion between teh wire and teh spade. may require replacenet. I solder these. the wire corrodes back into the insulation so cut way back to the harness and solder on new fresh extension wire or hot flux cleaning

2 soak your injectors overnight in inj cleaner

triggering an injector under electrical load may be intermittent even if teh meter reads voltage at teh wire. a corroded junction cant carry the amperage required to open it but still shows signal at the meter

use the baby food jar method to test each injector for proper flow and spray...

Get and use a remote starter switch so you can see it happen.

I've got 4 baby food jars on the way. I guess I should label each injector and record my results and then rotate the injectors and retest.

After retesting at different locations, assume a particular injector isn't spraying at all or is spraying significantly less than the others, then I assume I can conclude that injector is a problem. Should I then soak the injector in fuel injector cleaner?

If an injector sprays a certain amount at 3 locations but less or none at the forth, then I assume I have an electrical issue (connector, harness, trigger points, etc.).

On a side note, the L-Jet that was on my 1.8 motor functions fine. How does the 2.0 motor run with L-Jet compared to the D-Jet?

yeah, what you said
yup. L-jet on a 2.0
jar test!!!
soak em all
clean those ground points anyway
hurry up already, stop teasing us. we want to know.

Ljet runs fine on a 2.0 liter....if you give up and need to do it.
Its sized for it, it will run ok.

Yes, I soak the injectors overnight (typically a few days based upon how fast I need them)

You can do a psuedo scientific measurement...
I think 1.5 volts (an AA battery) will open the injector.
30psi (used fuel pump and regulator)

If you can get that hook up, run pure FI cleaner through them for a while...you should be able to watch the spray pattern.


Rich

I used the baby food jar method and injector #3 sprayed no fuel at all while the other 3 sprayed similar amounts. I turned the car over for exactly 10 seconds.

Then I swapped injector #3 for #4 and the same for 1 and 2 and repeated. As expected, injectors 1 and 2 sprayed the same amount. The non-firing injector (#3) again sprayed no fuel (now being fired by #4 electrical connector). #4 injector sprayed the same as 1 and 2.

Therefore, I concluded #3 is clogged. I'm not sure how this happened as I had them cleaned and tested. This injector was on #1 originally and that was the cylinder that had the broken spark plug connector (see picture below). Could this have fried the injector?

I will soak this injector for the next 2-3 days and then retest.

Click to view attachment

I doubt the bad connector has anything to do with the injector. Have you checked the injector with an ohm meter? Compare the resistance to the others, it could be shorted or open.

They all tested between 2.6 and 2.8 ohms.

would you like to borrow an injector?

Rich

Absolutely.

I have the injector soaking now. How do I remove the screen inside?

Dont. Its a metal end is peened over.

What color injector do you need...I forget..yellow?
I have a box full.

Try using an AA battery to open and close the injector.
ITS NOT 12 vdc...its more like 2-3 volts.
With no pressure, a single AA battery should do it.

rebuilt injectors do fail..frequently.

Rich

Green.

Quick update: I just got off the phone with Rich at Cruzin Performance who cleaned and tested my injectors. He believes the non-firing injector is stuck closed. They were cleaned and tested 3 months ago and have sat in their sealed bags until last week.

He finds that sometimes when the injector sits for a few months that the plunger gets stuck and the electromagnet isn't strong enough to unstick it. He recommended hooking up a 9 volt battery to the terminals and gently tapping on the outside of the injector. This I will try tonight and I'll report back.

Btw, he offered to unstick it for me if my attempts didn't work. Nice guy, answered the phone himself and spent 10 minutes with me on the phone.

Hopefully I will be soon!!!!

Well, I shipped the injector back on Friday and Rich unstuck it, retested it and sent it back the same day (no charge). I just put it in and the motor fired right up. Set the dwell and timing. I got the idle down to about 1600 before it would start to fall off. I'll look for vacuum leaks tomorrow, but I did go for about a 15 minute drive tonight with the top off.

Great news...sorry I dont live closer to be of more assistance with spare parts...
If we plan better, the kids come back and forth frequently....at least every two weeks.

For the vacuum leak.
Remove andplug everything except the mps...
See if you can get the idle down.
Then add one line at a time back...

Rich

Can a vacuum leak(s) cause the idle to oscillate between 1600 and about 400 rpms? I have the AAR plugged, no de-accel valve and no charcola cannister. I used the cooper RTV on the plenum gasket, cold start valve and intake to head spacers.

I used some starting fluid and I think I may have a small leak at the throttlebody shaft. I'm not sure if that would be enough. I'm not sure how to adjust the idle properly using the idle screw at the throttlebody and the knob on the ECU.

I'm just happy I don't see any oil leaks after replacing all the seals.

Throttle body gasket...remove and check it out.
Turn the knob to the middle and leave it alone (on the ECU)
That is only for idle mixture...not speed.

Did you clean a grease the distributor advance plates? they stick when hot and will drive you nuts..its a $0.05 job.

Is the idle hunting up and down alot, or is it dropping like a rock to 400 after you flip the throttle?

My idle speed (air bypass) screw is damn close to closed...that is how it should be. If you open that screw and nothing really changes...you have a vacuum leak....still.

Throttle body gasket (NLA) as Ed.
It could be made from rubber inner tube...not that I have done that or anything...
Clamp the bog hoses, both sides, that connect the plenum to the runners.
Ensure the plenum is airtight...no rust holes in the bottom..it happens...
Ummmm

Both head breather tubes are clamped
Oil filler gaskets all good, and cap (a test trick is take off the cover, saranwrap the top...then put the cover back on....just for a test.)

I have chased all this crap over the years...I remember once when I redid the whole intake....I needed a stronger spring on the throttle body....you know there is a spring...a return spring...long pull type spring.

Rich

- Plenum was cleaned and painted, no rust.
- throttlebody gasket is new (I bought one from a member here)
- intake runner sleeves clamped
-


I will check to make sure the butterfly is returning to fully closed. I also realized that I set the timing without disconnecting and plugging the advance vacuum line.

How is the best way to clean/lube the dizzy's advance plates?
There is no gasket or o-ring on the oil filler cap. Is there supposed to be one? I know L-jet caps have two.

Hey Rich, I found this while searching for how to clean the dizzy.

To funny...I forgot I did that.
I know why I did it...lol

Test it. activate the advance plates...see if it Snaps back...if not, its dirty.
Do this and keep and eye on that damn ball bearing...its fast.

rIch

FWIW, I got new bosch injectors out of New Jersey for about $50 a piece ,if you are still having problems with them.

Are those the Niehoff ones? I saw those at O'Reilly Auto/Kragen's website for the same price.

These are 0 280 150 019

regular yellow bosche box

I'm not familiar with Niehoff.

I believe yellow injectors are for the 1.7 but that part number is for the 2.0 injectors. Where did you get them?

Better stuck closed than stuck open. I had one stuck open, had no clue till i saw gas dripping out the exhaust. Also had an injector stuck closed. They are 35+ year old electromechanical devices, can't expect them to be perfect any more. I've sent injectors to Cruzin performance, excellent service!